NUTRITION AND WATER
General principles of a healthy diet:
Eat lots of fruits and vegetables.
Eat moderate amounts of whole grains (pastas, breads, cereals, and rice).
Eat moderate amounts of nuts and seeds (unsalted, not roasted)
Eat moderate amounts of fatty fish (BEWARE of tuna and farmed salmon)
Limit meat, especially red meat.
Limit fatty, greasy, fried foods.
Use low-fat or no-fat varieties for milk and milk products
Organic foods – see separate section near the bottom of this outline
Whole foods vs. refined foods: primitive diets vs. modern diets and physical degeneration (Weston Price, DDS. Nutrition and Physical Degeneration. 1939)
Weston Price’s review of the research in his “search for the cause of degeneration of the human face and dental organs” led him to conclude that “The evidence seemed to indicate clearly that the forces that were at work were not to be found in the diseased tissues, but that the undesirable conditions were the result of the absence of something, rather than the presence of something.” (16th Printing. 2004. Pg 21).
Weston Price thus decided in 1930 to travel the world and seek out primitive cultures with no exposure to the “white man’s diet” of refined grains, and analyze the nutrient content of these primitive diets, and correlate this information with careful analysis of the prevalence of dental caries (cavities) and deformities of the dental arch (the cause of the need for orthodontia).
Price visited the Eskimos in Alaska, native American Indians in multiple locations, African tribes, and Australian Aborigines.
He found that the diets were tremendously diverse, depending on geographic location. “Some were based on sea foods, some on domesticated animals, some on game and some on dairy products. Some contained almost no almost no plant foods while others contained a variety of fruits, vegetables, grains, and legumes…However, these diets shared several underlying characteristics…All the diets contained animal products of some sort and all included some salt” (16th Printing. Prologue. 2004. xv- xvi).
Price found that consumption of primitive diets was associated with a much lower incidence of dental caries, deformities of the dental arch, and tuberculosis!
Analysis of the primitive diets showed “that all contained at least four times the quantity of minerals and water-soluble vitamins of the American diet of his day” and “at least TEN times the amount of fat-soluble vitamins found in animal fats” (16th Printing. Prologue. 2004. xvi). He attributes much of the insufficiency of vitamins and minerals in the diet to depletion of the soil (pg 392).
USDA (United States Department of Agriculture) Guidelines for healthy eating:
1930's - The Basic 12 1940's - The Basic 7 1956 - The Basic 4
Milk, dairy products Milk, milk products Milk
Potatoes, sweet potatoes Tomatoes and fruits Meat
Dry peas, beans, nuts Leafy greens Veggies/fruits
Tomatoes/citrus fruits Other veggies/fruits Breads/cereals
Leafy greens/yellow veggies Butter and fat
Other vegetables and fruits Lean meat, poultry, fish
Eggs Flour and cereals
Lean meat, poultry, fish
Flour and cereals
Butter
Other fat
Sugar
Some argue that the creation of the "Basic Four" was heavily influenced by the meat and dairy industry lobbies. Either way, as scientific understanding of healthy nutrition advanced, it became clearer that the "Basic Four" was an inadequate guide for the public with regard to healthy eating.
The food pyramid released by the USDA in 1992 is an improvement conceptually, but not ideal.
The scientific limitation of the food pyramid based on emerging understanding of nutrition is that it does not distinguish between types of fat or types of carbohydrate and also does not distinguish the source of protein.
Note part of the objective of the USDA in 1992 was to keep things simple for the public
USDA EATING RIGHT FOOD PYRAMID
/ fats \
/ sweets \
/ milk, meat, nuts, eggs\
/ fruit, vegetables \
/ grains \
The USDA on 4/19/05 revealed ‘MyPyramid’ by turning the old food pyramid on its side, adding exercise in the form of steps up the side of the pyramid, and showing each food group as a triangle in the pyramid from the base to the apex, with the base representing healthier choices within the food group, such as whole grains as opposed to highly refined carbohydrates.
The food groups are grains, vegetables, fruits, milk, meat and beans, and oils.
There are 12 pyramids which provide quantities of food based on individual age, sex, and weight
More information at www.mypyramid.gov – this site is interactive and includes:
MyPyramid Plan – quick estimate of how much food to eat based on age, sex, and weight.
MyPryramid Tracker – more detailed information on individual diet quality and physical activity status.
Inside MyPyramid – in-depth information for every food group.
Start Today – provides tips and resources.
This pyramid is more representative of scientific understanding of nutrition than the 1992 pyramid, but many experts feel that it still has shortcomings.
A couple of examples include lack of attention to trans fats, and encouragement of excess consumption of dairy.
An excellent critique appears in Integrative Medicine: A Clinician’s Journal. 2005. 4 (6). 14-19.
Note that while there is published data that the Mediterranean diet is associated with increased longevity, lower incidence of metabolic syndrome, decreased risk of cardiovascular disease, and a reduced risk of death from cancer (see references in the section on Mediterranean diet at the bottom of this outline), there is no research to show that the MyPyramid dietary protocol reduces the risk of disease or death.
The USDA in June 2010 replaced ‘MyPyramid’ with ‘MyPlate,’
‘MyPlate’ divides the plate into approximate quarters, with just over ¼ of the plate with vegetables, just less than ¼ of the plate with fruit, ¼ of the plate with sources of protein, and ¼ of the plate with grains (and dairy as a side dish).- more info at www.choosemyplate.gov
A limitation of MyPlate is that the pictorial does not distinguish between refined grains and whole grains.
Diet – every 5 years the USDA (U.S. Department of Agriculture) and Department of HHS (Health and Human Services) jointly release the Dietary Guidelines for Americans. These guidelines serve as the foundation for federal nutrition policy and education and have far-reaching influences, including schools, government cafeterias, the military, food assistance programs, agricultural production, restaurant recipes, and industry food formulations. The Dietary Guidelines are finalized based upon the Dietary Guidelines Advisory Committee (DGAC) report in conjunction with comments from the public, advocacy groups, and industry.
They are based on recommendations from a 13 member advisory committee
The 2015 DGAC report is available at www.health.govDietaryGuidelines.
The guidelines contain 5 overarching goals, and 13 key recommendations (JAMA Viewpoint. 2016. 315. 457-458). Key recommendations include the following:
Consume less than 10% of calories per day from added sugars (new recommendation).
Consume less than 10% of calories per day from saturated fat.
Consume less than 2300 per day of sodium.
NOTE dietary cholesterol is no longer listed as a “nutrient of concern” based on recent scientific evidence showing no appreciable relationship between dietary cholesterol and serum cholesterol, or clinical cardiovascular events in general populations.
NOTE total fat is no longer listed as a “nutrient of concern” nor is there a recommendation to restrict total fat intake. Instead, the report concludes that replacing total fat with carbohydrate does not lower CVD risk, and dietary advice should focus on optimizing intake of certain types of fat.
NOTE that the USDA is the agency responsible for both the food pyramid and promoting the livestock industry, which is viewed by many as an institutional conflict of interest.
In 1991, Time magazine addressed this in an article entitled “Playing Politics with Our Food: While the Food and Drug Administration reforms labels, the Agriculture Department drags its feet, thanks to its cozy relations with the meat industry” (Time. 7/15/91. 57-58).
In 1999, the Physicians Committee for Responsible Medicine (PCMR) sued the USDA, charging that it had hidden from the public information about the background of some members of its advisory committee. It turns out that more than half of the 11 members of the advisory committee have ties to the meat, dairy, and egg industries.
PCMR won the lawsuit in 2000, so during the next revision of the guidelines after the 2001 revision, the advisory committee selection process must be made more public (Natural Health, 4/01).
Some nutrition experts recommend that the Department of Health and Human Services assume responsibility for revising the food pyramid, to avoid the above conflict of interest.
Food Politics (2002) by Marion Nestle, chair of the Nutrition Department at NYU, provides an excellent critique of this inevitable conflict of interest.
NOTE that research sponsored by manufacturers or groups with commercial interest was four to eight times more likely to be favorable than research that wasn’t industry sponsored, and most published studies nowadays are financed by organizations with commercial ties, rather than by the government (PLoS Medicine. 1/07).
Harvard School of Public Health Guidelines for healthy eating
Formulated by Walter Willett, MD, DrPH is an alternative construct which is representative of current scientific understanding of nutrition
Walter WIllett pyramid (1994)
/ red meat \
/ sweets \
/ butter \
/ fish, poultry, eggs\
/ dairy or Ca suppl \
/ nuts, legumes \
/ most veg oils \
/ fruits, vegetables \
/ whole grains \
HEALTHY EATING PYRAMID IN EAT, DRINK, AND BE HEALTHY (2001)
/__________red meat, butter__________\
/_____high glycemic index carbohydrates_____\
/__dairy food or calcium supplement 1-2 times/day__\
/__________fish, poultry, eggs 0-2 times/day__________\
/____________nuts and legumes 1-3 times/day____________\
/_______vegetables in abundance, fruits 2-3 times/day________ __\
/___________whole grain foods and plant oils__________________\
/ daily exercise and weight control _____\
Alcohol in moderation, multiple vitamin
University of Michigan Integrative Medicine Clinical Services guidelines
Developed and alternative pyramid, released 3/7/05, available as an interactive web-based nutrition tool at www.med.umich.edu/umim. Summary article: (Explore. 2006. 2. 352-356).
HEALING FOODS PYRAMID
/____Accompaniments___\
/_______Lean meats_______\
/___________Fish and seafood__________\
/________________Eggs and dairy_______________\
/____________________Seasonings and healthy fats________________\
/____________________________Legumes___________________________\
/____________________________________Grains___________________________________\
/______________________________________Fruits and vegetables_________________________\
/__________________________________________Water_________________________________________\
The American Institute for Cancer Research (AICR) guidelines
In 1999 launched the ‘New American Plate’ approach to meal planning – the plate is divided into 2/3 (or more) vegetables, fruits, whole grains, beans, and nuts and 1/3 (or less) sources of animal protein, including lean meat, poultry, fish, cheese, and yogurt.
Andrew Weil, MD has outlined an anti-inflammatory diet pyramid (www.healthyaging.com)
Macronutrient composition of the diet
Hunter-gatherer societies estimated macronutrient ratio:
19-35% protein, 22-40% carbohydrate, 28-47% fat (Mayo Clin Proc. 2004. 79. 101-108).
15-30% protein, 20-40% carbohydrate, 40-50% fat (Am J Clin Nutr. 2000. 7. 682-692).
US diet macronutrient ratios according to NHANES III: 15.5% protein, 49% carbohydrate, 34% fat, 3.1% alcohol.
Macronutrient guidelines from the Institute of Medicine (www.iom.edu) – 20-35% fat, 45-65% carbohydrate, 10-35% protein.
It is estimated that carbohydrates constitute 70-80% of calories consumed by humans globally.
Nutrition and Health
In 2012, 702,308 cardiometabolic (CMD) deaths occurred in US adults. It is estimated that 48.2% of these deaths (318,656) were associated with 10 dietary factors (JAMA. 2017. 317. 912-924 and editorial 908-909).
9.5% of CMD deaths were estimated to be due to excess salt intake
8.5% of CMD deaths were estimated to be due to low intake of nuts and seeds
8.2% of CMD deaths were estimated to be due to high intake of processed meats
7.8% of CMD deaths were estimated to be due to low intake of seafood omega-3 fats
7.6% of CMD deaths were estimated to be due to low intake of vegetables
7.5% of CMD deaths were estimated to be due to low intake of fruits
7.4% of CMD deaths were estimated to be due to high intake of sugar-sweetened beverages
5.9% of CMD deaths were estimated to be due to low intake of whole grains
2.3% of CMD deaths were estimated to be due to low intake of polyunsaturated fats
0.4% of CMD deaths were estimated to be due to low intake of unprocessed red meats
Fats
Old wisdom:
Polyunsaturated fat is best because it lowers total cholesterol.
Saturated fat is worst because it raises total cholesterol.
Monounsaturated fat is bad because it has a neutral effect on total cholesterol.
Total fat should be limited because of the association between fat intake and atherosclerosis.
New wisdom - the form of fat is important:
Omega 3 polyunsaturated fats are best for a variety of reasons (see below).
Mono-unsaturated fat is very good because it raises HDL and lowers LDL cholesterol.
Omega 6 polyunsaturated fats are essential in small amounts (3-6% of total calories, which is roughly one tablespoon daily) but should be limited because they may lower HDL cholesterol disproportionately, may trigger free radical chain reactions which increase the risk of cancer and atherosclerosis, and may lead biochemically to increased production of pro-inflammatory prostaglandins.
Saturated fat is okay in moderate quantities; even though it raises LDL cholesterol (bad cholesterol), it also raises HDL, and scientists are now questioning the past conclusions that saturated fat intake increases the risk of heart disease (Commentary. Ravnskov U et al. Mayo Clin Proc. 2014. 89. 451-453; Time. 6/23/14. 28-35).
Trans fat is worst - it lowers HDL cholesterol and raises LDL cholesterol, and has a number of other deleterious effects (see below).
Total fat intake can comprise up to 40% of total caloric intake, as long as it is predominantly good fats which are consumed.
Note all fats are calorie dense, containing 9 calories per gram whereas carbohydrates and protein contain 4 calories per gram. This is not bad per se but reminds us of the importance of limiting the quantity of fat consumed.
Note the National Academy of Sciences reported in 1989 that, contrary to previous popular wisdom, total fat intake alone is not associated with heart disease risk.
Note that the ratio of fat to carbohydrate used in the fuel mix for most cells in our body is determined by the prevailing insulin level - hyperinsulinemia (an insulin level that is always high such as in insulin resistant individuals) means the cells are constantly required to burn carbohydrate and dietary fat ends up stored as body fat instead of burned as fuel.
Structural categorization of fat.
Most dietary fat is in the form of triglycerides, which are composed of three fatty acid molecules bound together by a glycerol molecule.
Fatty acids are straight chain hydrocarbon chains with a methyl group (CH3) at one end and a carboxyl group (COOH) at the other end.
Saturated fat is composed of fatty acids with no carbon-carbon double bonds and is solid at room temperature, mono-unsaturated fat is composed of fatty acids with one carbon-carbon double bond and is liquid at room temperature, and polyunsaturated fat is composed of fatty acids with two or more carbon-carbon double bonds and is also liquid at room temperature.
The omega classification of fats is based on the location of the first carbon-carbon double bond, with carbons counted from the methyl end of the molecule.
Fatty acids are classified as very-short-chain (VSCFA) containing 2-3 carbon atoms, short-chain (SCFA) containing 4-6 carbon atoms, medium chain (MCFA) containing 8-14 carbon atoms, and long chain (LCFA) containing 16 or carbon atoms.
Fat in the body exists in two main structural forms:
Straight chain fatty acids – phospholipids, sphingolipids, glycosphingolipids. These are highly modifiable.
Ring-like structures –sterols – cholesterol, phytosterols. These are hydrophobic and rigid in structure.
Functional description of fat – it is a lipid (i.e. substances insoluble in water, soluble in organic solvents, and able to be used by the body).
Functions of fats - energy source, components of cell membranes, precursors to eicosanoids (prostaglandins, leukotrienes), precursors to hormones, regulate gene expression (via activation or inhibition of NF-KB and PPARs).
Butyric acid, a short chain fatty acid, is the preferred fuel for colonic epithelial cells (colonocytes).
Medium-chain triglycerides, and specifically those containing caprylic acid (8 carbon atoms) and capric acid (10 carbon atoms), have been shown to improve the course of many health problems such as pancreatic insufficiency, liver cirrhosis, epilepsy, and glycogen storage diseases.
Fat consumption and satiety
Mediated in part by release of CCK.
The research on satiety in experimental situations shows that fat consumption has a weak effect on satiety; consumption of low energy density foods such as fruits and vegetables has a stronger effect on satiety.
Essential fatty acids – omega 3 and omega 6 polyunsaturated fatty acids are essential in mammals because mammals do not synthesize desaturase enzymes that can insert a double bond closer than 7 carbon atoms away from the methyl end of the carbon chain.
Saturated fat
Saturated fat includes animal fat (red meat, poultry skin, milk products), and tropical oils (palm oil and coconut oil).
As compared with carbohydrate intake, saturated fat intake raises HDL, lowers triglycerides, and has minimal effect on Apo B, based on a meta-analysis of 60 controlled trials (Am J Clin Nutr. 2003. 77. 1146-1155).
Saturated fat consumption and risk of coronary heart disease – the generally accepted conventional dogma is that saturated fat consumption is associated with an increased risk of coronary artery disease.
Historically, this association was based on interpretation of data from 16 cohorts in the Seven Countries Study (Keys A. Circulation. 1970. 41 [Suppl 1]. 1-211).
Critics of this conclusion indicate significant heterogeneity in the data, and various ways of interpreting the same data (Commentary. Ravnskov U et al. Mayo Clin Proc. 2014. 89. 451-453).
Recent analysis of data from the Seven Countries Study shows that processed foods, consisting primarily of carbohydrates, were misclassified as saturated fats (Food Nutr Sci. 2013. 4. 240-244).
The American Heart Association diet-heart guidelines published in 1982 were based in part on Keys’ interpretation of his data; this interpretation was questioned in a 1983 paper (Temple NJ. Med Hypotheses. 1983. 10. 425-435).
Many prospective cohort studies show a correlation between saturated fat consumption and risk of coronary artery disease
These studies include the Nurses’ Health Study in 80,082 women (N Engl J Med. 1997. 337. 1491-1499) and the Ireland Boston Diet-Heart Study in 1001 men (N Engl J Med. 1985. 312. 811-818).
Additional data supporting a link between saturated fat consumption and risk of coronary artery disease comes from cross-population studies such as the Japan-Honolulu-San Francisco Study in 11,900 men (J Chronic Dis. 1974. 27. 345-364).
Of note, data from the Nurses’ Health Study indicates that replacing 5% of energy from saturated fats with energy from nonhydrogenated, unsaturated fats could reduce the risk of CHD by 42% (N Engl J Med. 1997. 337. 1491-1499).
There is however data that fails to show an association between saturated fat consumption and risk of coronary artery disease
In terms of cross cultural data, in two Polynesian populations living near the equator, saturated fat intake is very high, estimated at 47% of total energy, mostly from coconut, but vascular disease is uncommon (Am J Clin Nutr. 1981; 34:1552-1561).
The observed association between saturated fat consumption and risk of coronary artery disease in many studies may be a function on how the foods are prepared. Specifically, the association between saturated fat consumption and risk of coronary artery disease might be a function advanced glycation end products and cholesterol oxides which form during the cooking and processing of foods such as dairy and meat (cited by Alan Gaby, MD in a Commentary in Townsend Letter. June 2010. Pg 24).
A meta-analysis of 16 observational studies reported that high-fat dairy intake was inversely associated with adiposity, and was not associated with diabetes or CVD (Lipids. 2010. 45. 925-939).
Meta-analyses of prospective epidemiologic studies fail to find an association between saturated fatty acid intake and CVD mortality (J Clin Epidemiol. 1998. 51. 443-460; Am J Clin Nutr. 2010. 91. 535-546).
A meta-analysis of 21 prospective cohort studies in a total of 347,747 subjects, and with 5 to 23 years of follow up failed to show a correlation between saturated fat consumption and risk of coronary artery disease, stroke, or cardiovascular disease, even when adjusted for age, gender, and study quality (Am J Clin Nutr. 2010. 91. 535-546).
A meta-analysis of 7 RCTs (n=11,275) with follow up of 2-8 years reported that replacing saturated fatty acids with omega 6 polyunsaturated fatty acids (3 trials) or mixed omega 3/omega 6 polyunsaturated fatty acids did not reduce all cause or coronary heart disease mortality (the substitution of mixed omega 3/omega 6 polyunsaturated fatty acids was associated with a 20% reduction of cardiovascular mortality, NNT of 32) [BMJ. 2013. 346. e8707).
A meta-analysis of 16 long-term cohort studies found a reduction in risk of all-cause death, ischemic heart disease, stroke, and diabetes in those individuals with the highest dairy consumption, relative to those with the lowest dairy consumption (Eur J Nutr. 2013. 52. 1-24).
A March 2014 meta-analysis of nearly 80 studies involving more than a half million subjects, published in the Annals of Internal Medicine, fail to report an association between saturated fat intake and cardiovascular disease (as cited in Time. Don’t Blame Fat. 6/23/14. Page 32).
Saturated fat consumption and cholesterol levels
It is “conventional wisdom” that saturated fat raises LDL cholesterol. This conclusion is supported by a published meta-analysis of 27 trials (Arterioscler Thromb. 1992. 12. 911-919). Saturated fats in butter and other dairy products have the most detrimental effect on LDL cholesterol, saturated fats in meat have a less detrimental effect, and saturated fats in chocolate have the least detrimental effect on LDL, as per Walter Willett (Eat, Drink, and Be Healthy. 2001). Stearic acid (the fat in chocolate) is rapidly converted into oleic acid, a mono-unsaturated fat.
HOWEVER, the effect of high intake of saturated fatty acids on serum cholesterol is weak and transient in some clinical studies (J Clin Epidemiol. 1998. 51. 443-460); and 10 RTs or crossover trials have found that a high intake of saturated fatty acids, as high as 50% of total caloric intake, has minimal effect on total or LDL cholesterol (Ravnskov U. Is Saturated Fat Bad? In Modern Dietary Fat Intakes in Disease Promotion. New York, NY. Humana Press. 2010. 109-119).
FURTHERMORE, saturated fat intake predominantly increases large, buoyant LDL levels, and this large, buoyant LDL seems to have a neutral effect on cardiovascular risk, whereas small, dense LDL (increased by high carbohydrate intake) is associated with increased cardiovascular risk.
Saturated fat also raises HDL cholesterol levels.
Conventional wisdom - it is best to take less than 10% of calories from saturated fat.
Monounsaturated fat
Includes avocados, canola oil, olives, olive oil, and various nuts and seeds.
Olive oil is composed primarily of oleic acid, and omega 9 fatty acid.
Monounsaturated fat intake is associated with lower levels of LDL and total cholesterol, protection against thrombogenesis, reduced LDL susceptibility to oxidation, and better glycemic control (J Nutr. 1999. 129. 2280-2284). In a 12 week crossover trial in 26 college students, those consuming a high monounsaturated fat diet showed less lipid peroxidation than those consuming a high polyunsaturated fat diet (Am J Clin Nutr. 1991. 53. 899-907).
Monounsaturated fat consumption is correlated with a decreased risk of coronary heart disease, based on data from prospective cohort studies such as the Nurses’ Health Study in 80,082 women (N Engl J Med. 1997. 337. 1491-1499), cross population studies such as the Seven Countries Study in 12,770 men (Circulation. 1970. 41 [4 suppl]. 1-198), and epidemiologic studies such as the Coronary Mortality in France and Finland study (Circulation. 1993. 88. 2771-2779). HOWEVER, a systematic review and meta-analysis of observational and RCT trial data concluded “we saw a null association of total and individual monounsaturated fatty acids with coronary risk in studies using both dietary intake and circulating fatty acid composition. This apparent lack of association is consistent with available mechanistic data, which remain contradictory about whether monounsaturated fatty acids promote or protect against atherosclerosis” (Ann Intern Med. 2014. 160. 398-406).
BEWARE monounsaturated fat created by hydrogenation of polyunsaturated fat (i.e. stick margarine) is unhealthy because hydrogenation creates trans-configuration fatty acids (see ‘trans fats’ below).
Polyunsaturated fats (PUFA) – these are essential; they cannot be synthesized in the human body (a fact known since 1929)
Omega 3 fatty acids
These are found in fish in the form of EPA (eicosapentanoic acid) and DHA (docosahexanoic acid) and in vegetable sources in the form of ALA (alpha linolenic acid).
ALA is a short chain fatty acid and EPA and DHA are long chain fatty acids - in the human body, only about 15% of ALA is converted to EPA and only about 5% to DHA, and there are a number of identifiable factors which can inhibit this conversion even further (Am J Clin Nutr. 1999. 70. 560S-569S; Curr Opin Clin Nutr. 2004. 7. 137). Conversely, GLA may facilitate conversion of ALA to EPA.
Omega 3 fatty acid content of fish (grams EPA + DHA per 3 ounce serving) - atlantic salmon (1.8), atlantic herring (1.7), whitefish (1.4), pink canned salmon (1.4), bluefin tuna (1.3), atlantic mackerel (1.0), wild rainbow trout (1.0), bluefish (0.8), sardines canned in oil (0.8), blue mussels (0.7), swordfish (0.7), white tuna canned in water (0.7), freshwater bass (0.6). See Consumer Reports 7/03 page 32 for a complete listing of other fish with lesser amounts of DHA (docosahexanoic acid) and EPA (eicosapentanoic acid).
Omega 3 fatty acid content in vegetable sources (7.6 grams ALA per tablespoon of flax oil, 1.6 grams ALA per tablespoon of canola oil, 1.5 grams of ALA per tablespoon of walnut oil, 2.1 grams of ALA per 3.5 ounces cooked soybeans).
Mechanisms of action of omega 3 polyunsaturated fatty acids (PUFAs) Consumer Reports 7/03
Antiarrhythmic - they may electrically stabilize the heart muscle cells and thus reduce the risk of sudden death due to an arrhythmia. This protection may be effective only for arrhythmia induced by ischemia.
Anti-cancer effects – reduce inflammation, reduce angiogenesis, decrease oncogenes, induce cell differentiation, suppress NFKB, suppress apoptosis blocker bcl-2, reduce cachexia (J Nutr. 2002. 132. 3508S-3512S).
DHA reduces insulin resistance in overweight patients, and appears to improve cell membrane receptor function and signal transduction.
DHA lowers blood pressure.
Decrease free radical production.
High doses reduce the serum triglyceride level, raise HDL, decrease Lp (a), and increase particle size of LDL.
They may increase heart rate variability (Chest. 2005. 127. 1102-1107).
Increase vasodilatation.
Improved systemic arterial compliance.
Improve endothelial function.
Antiatherosclerotic - they may make the arteries more elastic, reducing the risk of high blood pressure triggering plaque rupture. They may also stabilize plaque - data from a RCT in 188 patients randomized to receive sunflower oil versus fish oil supplements prior to a scheduled carotid endarterectomy found that those who received the fish oil had had thicker fibrous caps covering the carotid plaque (Lancet. 2003. 361. 477-485).
Antithrombotic - they may decrease the stickiness of platelets, reducing the risk of forming a blood clot. Decrease fibrinogen and decrease blood viscosity.
Anti-inflammatory - they are converted into anti-inflammatory eicosanoids (prostaglandins and leukotrienes), and thus may stabilize arterial plaque. EPA inhibits D5D enzyme which converts DGLA to arachidonic acid. In a primary prevention trial, those patients treated with 1.4 grams of fish oil daily showed significant decrease in inflammatory markers hsCRP, TNF alpha, interleukin-6, and leukotriene B4, as compared with placebo (Micallef MA et. al. Atherosclerosis. 9/27/08. epub).
For therapeutic uses of omega 3 fatty acids, including supplements, return to Home Page, click on “Dietary Supplements” and scroll to ‘Fatty acids’ then scroll on to ‘Fish oil capsules.’
Omega 6 fatty acids
These are found primarily in vegetable oils (corn, safflower, sesame, soy, and sunflower).
These oils are added to many baked goods and prepared foods.
Cattle are now fed soy meal and corn meal, often rather than grazing, so the fat in animals is composed of predominantly omega 6 fatty acids.
Note pasture raised animals are likely to have more omega 3 fatty acids and less omega 6 fatty acids than animals fed corn meal or soy meal.
LA (linoleic acid) is the fatty acid which is the biochemical precursor to all other omega 6 fatty acids in the body.
Omega 6 fatty acids can be converted either into pro-inflammatory or anti-inflammatory eicosanoids, with research ongoing to determine factors which influence which biochemical pathway is followed.
There is controversy regarding whether higher intake of omega 6 fats is good or bad:
Historically, tens of thousands of years ago, it is estimated that the dietary intake of omega 6 polyunsaturated fatty acids to omega 3 polyunsaturated fatty acids was 2:1 or even1:1, with 25-50% of protein derived from aquatic sources. Data to support this 1:1 ratio includes carbon and nitrogen isotope measurement of femur collagen, paleoarcheologicalsamples, dental wear patterns, cave art, and artifacts (Richards et al. Proc Natl Acad Sci. 2001). The ratio of omega 6 to omega 3 in the standard American diet is estimated at 20:1 (Am J Clin Nutr. 1999. 70. 560S-569S). An optimal ratio of omega 6 to omega 3 fatty acids is believed to be 4:1 (Am J Clin Nutr. 1999. 70. 560S-569S).
There is evidence that omega 6 fats promote inflammation, thrombosis, and insulin resistance (Lipids. 2001. 36. 1007-1024; Ann N Y Acad Sci. 1997. 827. 287-301; Eur J ClinInvest. 1997. 27. 780-787).
Administration of omega 6 fatty acids removes EPA from cell membranes, relocating EPA from phospholipids to triacylglycerols (J Lipid Res. 1992. 33. 1431-1440). Evidence suggests that EPA must be incorporated into cell membrane phospholipids in order to exert its beneficial effect on eicosanoid metabolism.
There is competing evidence that linoleic acid decreases thrombosis (Am J Clin Nutr. 1997. 65. 1687S-1698S), decreases arrhythmias (Am J Clin Nutr. 1991. 53. 1047S-1049S), and improves insulin sensitivity (Diabet Med. 2002. 19. 456-464).
In a population-based cohort of 1551 middle-aged men whose dietary composition was estimated with a 4-day food record, linoleic acid intake was correlated with a cardioprotective benefit over a 15-year follow-up (Arch Intern Med. 2005. 165. 193-199).
A review of the evidence article concludes that “the relevance of the concept of omega 6: omega 3 ratio to CHD risk is unclear” (Altern Ther Health Med. 2005. 11(3). 24-30).
The first step, and also the rate limiting step, in biochemical conversion of both ALA and LA into longer chain fatty acids is catalyzed by the D6D enzyme - this enzyme requires zinc, magnesium, and vitamins B3, B6, and C as cofactors. Furthermore, hypercholesterolemia, trans fats, and excess sugar consumption impair D6D function (Nutr Clin Pract. 1992. 7. 179-186).
All polyunsaturated fats are biochemically unstable - exposure to heat or air or light cause biochemical breakdown of the fat and free radical chain reactions which may predispose one to atherosclerosis or cancer, and may increase the risk of inflammatory diseases, degenerative diseases, and immune system disorders. For information on how to prevent biochemical breakdown of polyunsaturated fatty acids, scroll down in this outline to ‘Oils.’
CLA, conjugated linoleic acid, is a trans chemical configuration polyunsaturated fat found in small amounts in meat and dairy products which shows promise as a dietary supplement in reducing body fat (Am J Clin Nutr. 2004. 79. 352), increasing muscle mass, and possibly preventing cancer.
One of the isomers acts like ALA, a polyunsaturated fat which inhibits the enzyme responsible for synthesis of precursors of both pro-inflammatory and anti-inflammatory eicosanoids.
However, one of the isomers in the synthetic version (i.e. dietary supplement) causes an increase in insulin resistance in humans, as per Barry Sears, PhD (The Anti-Inflammation Zone. 2005. Pg 90).
Trans (chemical configuration) fats
Existence discovered in late 1800’s
Natural trans fats - present in very small quantities in dairy and meat products from cows, goats, sheep, and other ruminants (i.e. CLA). These are not considered a health risk.
Artificial trans-fats – introduced by Proctor and Gamble in 1911 (Perspective. N Engl J Med. 2014. 370. 1773-1775). Consumption is a known health risk
Fat which is chemically altered either as part of the manufacturing process or by repeatedly heating cooking oils past their smoking point. Trans fatty acids are made by adding hydrogen to polyunsaturated oil molecules (usually omega 6 fats) under high temperature and pressure. Nickel is typically used as a catalyst, then removed by filtration at the end of the manufacturing process. The end result chemically is that hydrogen atoms end up on opposite sides of the fatty acid molecule at the site of a double bond. This alters the structure of the fatty acid (individual molecules elongate and pack closer to one another) and this alteration of structure at a molecular level interferes with the function of the fatty acids in the cell membrane (i.e. altered receptor structure interferes with cell signaling).
Partial hydrogenation was patented in 1903; Crisco in 1911 was the first product marketed with artificial trans fats (Perspective. Ann Intern Med. 2009. 151. 129-134).
At the turn of the century, 79% of US trans-fat consumption is artificial trans-fats; 21% is from meat and dairy (FDA Consum. 2003. 37. 20-26).
In 2005 in the North America, 25 billion pounds of edible oils were consumed, and more than 9 billion of these were artificial trans fats (Circulation. 2007. 115. 2231-2246).
Reasons that manufacturers use trans fatty acids
Prolongs shelf life (i.e. delays rancidity).
Creates a solid out of a semi-solid (i.e. margarine).
Stable during deep frying.
In cookies and crackers and baked goods it is less expensive for the manufacturer to create trans fats than to use saturated fats.
In some snack foods, market research shows that the trans-fat is associated with good taste or ‘mouth feel.’
Trans fats in the food supply
Trans fats are found in many snack foods, some margarines, some peanut butter spreads, some breads, and some dry cereals.
Deep-fried fast food products in restaurants may contain 10 grams of trans fat per serving!
In 2000, estimated that trans fats compose 3% of calories in standard American diet, which corresponds to 6 gm/day in an individual consuming 2000 calories per day.
Historically, it was thought that using trans-fats (i.e. margarine) in place of saturated fat (i.e. butter) would be of benefit to individuals; it was hoped that trans fats would have the same favorable effects on lipid profile as natural unsaturated fats. Scientists have known for years though that this notion was incorrect - trans fats increase LDL cholesterol levels as much as saturated fat, but also lower HDL cholesterol levels, whereas saturated fat typically raises HDL, so the effect of trans fats on the lipid profile is double the bad effect of saturated fat (N Engl J Med. 1999. 340. 1994-1998).
Harmful effects of trans fats – studies in the early 1990’s began to reveal harmful health effects, and by mid-2000’s it became clear from scientific study that trans-fats had a number of deleterious health effects (Perspective. N Engl J Med. 2014. 370. 1773-1775).
Trans fats increase lipoprotein a, raise LDL cholesterol, raise triglycerides, and lower HDL cholesterol (N Engl J Med. 1990. 323. 439-445; J Lipid Res. 1992. 33. 399-410; Am J Clin Nutr. 1994. 59. 861-868; N Engl J Med. 1999. 340. 1933-1940; J Nutr. 2001. 131. 242-245; Am J Clin Nutr. 2003. 7. 1146–1155).
Trans fat intake increases hs-CRP (J Nutr. 2005. 135. 562-566).
Trans fats may be associated with activation of systemic inflammatory responses and endothelial dysfunction (Atheroscler Suppl. 2006. 7. 29-32).
Trans fats may increase the risk of becoming obese, via binding to PPAR nuclear receptors (Hyman M. Ultrametabolism. 2006).
Trans fats interfere with B and T cell functions, impairing immune system function.
Trans fats increase insulin resistance, and increase the risk of developing diabetes.
Trans fats may interfere with fertility.
Trans fats interfere with normal cell membrane function.
Epidemiologic data shows that a diet high in trans fats is associated with a significantly increased risk of coronary heart disease. A 2% increase in the energy intake from trans-fat is correlated with a 14-36% increase in the incidence of coronary heart disease – 14% in the ATBC Cancer Prevention Study in 21,930 male smokers (Am J Epidemiol. 1997. 145. 876-887), 28% in the Zutphen Elderly Study in 667 men (J Nutr. 2001. 131. 242-245), 33% in the Nurses’ Health Study in 80,082 women (N Engl J Med. 1997. 337. 1491-1499), and 36% in the Health Professionals Follow-Up Study in 43,757 men (Lancet. 2001. 357. 746-751). Data from the Nurses’ Health Study in 80,082 women indicates that replacing 2% of energy from trans fats with energy from nonhydrogenated, unsaturated fats could reduce the risk of CHD by 53% (N Engl J Med. 1997. 337. 1491-1499). For more information on trans fats and coronary heart disease, return to the Home Page and go to the outline on ‘Prevention of MI’ and the first section on ‘Primary Prevention.’
Epidemiologic data shows that a diet high in trans-fats is associated with an increased risk of cancer.
Regulation of trans fats (Perspective. N Engl J Med. 2014. 370. 1773-1775).
Denmark banned partially hydrogenated oils in 2003
In 2006, New York City passed a ban on trans fats in restaurant foods
Effective 1/1/06 (based on a 1999 FDA ruling), the trans-fat content of all foods is included in the ‘Nutrition Facts’ box on the label.
The caveat is that the FDA allows foods with less than ½ gram of trans fat per serving to list 0 grams of trans fat in the ‘Nutrition Facts’ box.
Foods with less than ½ gram of trans fat per serving still must show this information in the ingredients list – look for the terms ‘partially hydrogenated vegetable oil’ or ‘vegetable shortening’ in the ingredients list.
In 2008, California passed a ban on trans fats in restaurant foods
In 2014, the FDA has proposed a regulation which would declare partially hydrogenated oils unsafe (not GRAS), and thus they would need to be regulated as a food additive rather than a food. If implemented, the effect of this regulation would be to allow only a small amount of trans fats in food.
FDA mandated in 2018 that manufacturers stop using trans fats in processed foods; some manufacturers were allowed to continue to add trans fats to food until 2021
Interesterified Fat
Created by chemically inserting saturated fatty acids into the molecular backbone of vegetable oil to make it more stable (Consumer Reports on Health. 1/09. Pg 12).
Some manufacturers are using this form of fat in place of trans-fats; it is unclear though whether interesterified fat is any less harmful than trans-fat.
Carbohydrates
Old wisdom:
Refined carbohydrates like white flour and polished rice are acceptable alternatives in the diet to whole grains - they are just as good as energy sources.
The only disadvantage of refined carbohydrates is that they don't have the additional fiber and vitamins.
New wisdom - the form of the carbohydrate is very important:
Refined carbohydrates like white flour and polished rice can deplete the body of nutrients and they temporarily raise insulin levels, which then leads to a drop in blood sugar and hunger a few hours later. Refined carbohydrates and sugar may also suppress immune system function.
The insulin level at a given instant determines the ratio of fat to carbohydrate used in the fuel mix for most cells in our body - the higher the insulin level, the more carbohydrate in the fuel mix. The less fat in the fuel mix for the cells, the more dietary fat is converted into fat stores in the body (i.e. adipose tissue).
Scientists have learned that the glycemic index of carbohydrates is very important. For information on the glycemic index of specific foods, go to www.glycemicindex.com.
Note food sources of carbohydrate include fruits and vegetables and grains - grains are generally more calorie dense than fruits and vegetables (i.e. more calories per unit size) and thus it is easier when consuming grains to inadvertently consume excess calories.
Functions of carbohydrates - energy source, structural element in plant cell walls, structural element in myelin sheath of nerves, cell adhesion, cell development and differentiation, and cell to cell communication.
Structural classification of carbohydrates.
Monosaccharides - 1 saccharide.
Disaccharides - 2 saccharides.
Polysaccharides - more than 10 monosaccharides.
Classification of carbohydrates as simple versus complex carbohydrates.
Specific chemical meaning - simple refers to monosaccharides and disaccharides, complex refers to polysaccharides (this classification does not account for oligosaccharides).
For many years it was automatically assumed that starches would be slowly digested and absorbed, and a few simplistic experiments on raw starches and pure sugars supported this assumption, so for decades this was taught as fact in nutrition courses.
The classification of carbohydrates as simple versus complex is not meaningful from a physiologic perspective.
Some "simple" monosaccharides can have a very complex metabolic role.
We have known since the 1980's, when scientists finally started to study the actual blood-glucose response to common foods (i.e. how the carbohydrates in food change the blood sugar level), that many complex carbohydrates have a greater short term effect on raising the blood sugar than do "simple" disaccharides.
Functional classification of carbohydrates
Sugars - monosaccharides and disaccharides, including glucose, galactose, fructose, maltose (glucose + glucose), sucrose (table sugar: glucose + fructose), and lactose (milk sugar: glucose + galactose).
Glucose – 6 carbon sugar, consumption of which potentially stimulates insulin secretion, promoting glycogen synthesis in the liver and glucose uptake by tissues throughout the body.
Fructose (Viewpoint. JAMA. 2013. 310. 33-34).
6 carbon sugar; more than twice as sweet as glucose.
Highly concentrated in honey, fruits, and some vegetables).
Fructose does not directly stimulate insulin secretion and the consequent increase in leptin, a satiety hormone.
Fructose is taken up almost exclusively by the liver, and rapidly undergoes glycolysis.
Fructose does not require insulin for absorption into cells – once inside the cells it becomes an uncontrolled source of carbon (acetyl Co-A).
Fructose is a highly reactive reducing sugar, and therefore promotes the formation of advanced glycation endproducts.
Feeding studies show adverse metabolic effects associated with intake of fructose – these studies have been criticized for providing unrealistically high amounts of fructose in isolation, and thus the significance of findings from feeding studies is questionable. A meta-analysis found no adverse effects of isocaloric substitution of fructose and glucose at average consumption levels for body weight (Adv Nutr. 2013. 4. 246-256).
The fructose in fruits and vegetables is not considered problematic because the fiber in fruits and vegetables markedly slows absorption of the fructose from the GI tract. Observational studies show an inverse association between fruit consumption and body weight or obesity associated diseases (J Hum Hypertens. 2007. 21. 717-728).
References:
Gaby AR. Adverse effects of dietary fructose. Altern Med Rev. 2005. 10. 294-306.
Sievenpiper JL et al. Effect of fructose on body weight in controlled feeding trials. Ann Intern Med. 2012. 156. 291-304.
High fructose corn syrup (HFCS)
NOTE, from 1970 to 1997, annual per capita consumption of high fructose corn syrup (HFCS) increased from 0.5 pounds to 62.4 pounds, while sucrose consumption decreased from 102 pounds to 67 pounds per year.
Intake of HFCS may be more detrimental than intake of sucrose.
HFCS contains 97% monosaccharides (55% fructose, 42% glucose).
Whereas sucrose requires hydrolysis by a gut disaccharidase before its components are absorbed, the fructose and glucose in HFCS are presumably absorbed more rapidly. In the presence of even small amounts of glucose, the absorption of fructose is markedly enhanced, through facilitated transport.
In a study of 48 young, generally healthy adults, comparing consumption of 25% of daily energy as beverages sweetened with high-fructose corn syrup, as compared with 25% of daily energy as glucose, those consuming the high-fructose corn syrup showed a 40% increase in postprandial triglycerides at 2 weeks (J Clin Endocrinol Metab. 2011. 96. 1596-1605).
Consumption of high fructose corn syrup is strongly correlated with fatty liver, hypercholesterolemia and hyperlipidemia – this may be a causal relationship.
May be contaminated with mercury, as a consequence of chlor-alkali products used in its manufacturing (Environ Health. 2009. 8. 2).
Sucrose (table sugar). Sucrose is a disaccharide of glucose and fructose.
Sucrose is a food that may have drug-like effects in some people.
Sucrose is intertwined with our psychology - it is often a reward.
Sucrose is ‘empty calories’ – it dilutes nutrient levels in the diet.
Some health experts believe that sucrose causes immune system suppression. Ingestion of 100 grams (25 teaspoons) transiently reduces neutrophil phagocytosis (Am J ClinNutr. 1973. 26. 1180-1184).
Sucrose may reduce HDL cholesterol levels; increase serum triglycerides, uric acid, cortisol, and blood pressure; and increase platelet aggregation and fasting serum insulin - this occurs in about one-third of the population (Postgrad Med J. 1969. 45. 602-607; Ann Nutr Metab. 1983. 27. 425-435).
Sucrose intake may exacerbate chronic candidiasis in sensitive individuals.
In sensitive individuals, high sucrose intake contributes to anxiety, depression, fatigue, migraines, PMS, and tension headaches
Despite protest from the food lobby, the World Health Organization in 2002 recommended that a healthful diet should contain no more than 10% of calories from sugar that are not inherently part of a food (i.e. lactose in milk, fructose in fruit). This 10% figure corresponds to 50 grams (13 teaspoons) in a 2000 calorie diet - the average American eats more than twice that much sugar!
Data in 127,536 individuals in the Nurses’ Health Study and the Health Professionals Follow-up Study showed a 10% increased relative risk of CHD in those with high intake of refined starches and added sugars. HOWEVER, consumption of whole grains was associated with a 9% decreased relative risk of CHD (J Am Coll Cardiol. 2015. 66. 1538-1548).
A systematic review and dose-response meta-analysis of prospective cohort studies (n = 624,128) reported that consumption of total sugars, sucrose or fructose was not associated with a linear dose-response increased incidence of cardiovascular disease (CVD), but consumption of total sugars and fructose alone was associated with an increased risk of CVD mortality (Mayo Clin Proc. 2019. 94. 2399-2414).
Sucrose consumption was surprisingly associated with a decreased risk of CVD mortality, and added sugars surprisingly were not significantly associated with CVD mortality.
A dose response analysis found thresholds below which additional intake did not alter CVD mortality - the thresholds were 26% of calories from total sugar intake, 11% of calories from fructose intake and 13% of calories from added sugars (NOTE these thresholds are higher than current consumption by most of the American population).
Many associations found in the general population were affected by sensitivity analyses, suggesting from this epidemiologic data that effects of sugar consumption may vary significantly based on the population being investigated.
Note that over 200 monosaccharides occur naturally in plants, but the human body is known to use fewer than 10.
The only monosaccharides commonly included in the current Western diet are glucose, fructose, and galactose - the others can be synthesized from these two in the human body, but many factors may interfere with adequate synthesis.
Other important monosaccharides from a functional perspective include mannose, fucose, xylose, N-acetylglucosamine, N-acetylgalactosamine, and N-acetylneuraminic acid.
Oligosaccharides - 2 to 10 saccharides.
Includes fructo-oligosaccharides (FOS), galacto-oligosaccharides, and soy oligosaccharides.
Fructo-oligosaccharides (FOS) and galacto-oligosaccharides escape degradation in the upper GI tract and travel to the large intestine where they selectively support the growth of friendly bacteria which break down undigested carbohydrates into short chain fatty acids which supply 70% of the energy used by the colonic epithelial cells.
Fructo-oligosaccharides are breakdown products from inulin, which is a polysaccharide composed of repeating fructose units with a terminal glucose unit.
Many proteins have oligosaccharide side chains – see ‘glycobiology’ below for more details on the function of oligosaccharides in glycoproteins.
Starch
Polysaccharides which function as the predominant food reserve in plants.
Chemically labeled as either amylose (straight chain glucose polymers) or amylopectin (branched-chain polymers of glucose).
Amylose is less susceptible to digestion than amylopectin due to the tight physical structure.
Biochemically labeled as either rapidly digestible starch, slowly digestible starch, or resistant starch, based on the amount of amylase versus amylopectin – glycemic index is highest for rapidly digestible starch.
Resistant starch when acted upon by friendly bacteria in the colon produces short chain fatty acids (propionate, acetate, butyrate) which supply fuel for colonic epithelial cells.
Fiber
Large carbohydrate molecules (polysaccharides) not broken down by human digestive enzymes (i.e. indigestible).
Fiber is distinguished from starch in that it is a component of cell walls in plants.
Fermented in the colon by bacteria - produces methane gas (flatulence) and short-chain fatty acids which are the energy source for colonic epithelial cells.
Soluble fiber - can be dissolved in water (i.e. forms a colloidal suspension in water).
Some gums, some pectins, some hemicellulose.
Typically found in fruits, vegetables, and nuts.
Delays gastric emptying, increases satiety, decreases cholesterol, glucose, and insulin levels.
Along with resistant starch (see above) serves as fuel for colonic epithelial cells.
Insoluble fiber - cannot be dissolved in water (i.e. does not form a colloidal suspension in water).
Cellulose, some hemicellulose, some pectins, some lignins.
Typically found in cereal.
Creates fecal bulk, binds toxins and bile salts, and decreases the risk of constipation, diverticulosis, and possibly hemorrhoids and colon cancer.
Like resistant starch, acted upon by friendly bacteria in the colon and degraded to short chain fatty acids (propionate, acetate, butyrate) which supply fuel for colonic epithelial cells.
Note the categorization of fiber by the foods that contain it (i.e. cereal fiber, fruit fiber, vegetable fiber) used in many epidemiological studies is not nearly as meaningful from a functional standpoint as the classification of fiber as either soluble or insoluble.
Note that konjac root fiber (glucomannan) and rye fiber appear more potent at lowering cholesterol and blood sugar than wheat fiber, psyllium, oat fiber, or guar gum. Konjac root and rye fiber are sometimes referred to as ‘superfibers.’
The National Cancer Institute recommends 25-35 grams per day of fiber in the diet.
Worldwide consumption of fiber averages 50-75 grams per day.
Intake in the Paleolithic diet estimated at 100-150 grams per day.
Epidemiologic studies indicate that consumption of 75-100 grams of fiber per day may be ideal.
Average consumption in the U.S. is less than 10 grams per day.
One tablespoon of Metamucil contains 3 grams of fiber - 2.4 grams of this is soluble fiber.
One must increase water intake when one increases fiber intake, or the increased fiber can actually worsen constipation.
Increase the amount of fiber in the diet gradually to avoid GI distress.
Fiber intake can affect estrogen status – higher fiber intake is associated with higher serum concentrations of SHBG (and thus less free estrogen) and higher fiber intake is associated with decreased activity of beta-glucuronidase (and thus less enterohepatic recirculation of estrogen).
Remember that fiber may be antigenic (i.e. gluten intolerance).
Remember that fiber will interfere with absorption of vitamins and minerals consumed at the same time.
Fiber and health outcomes
Dietary fiber intake was associated with a significantly lowered risk of total mortality in both men and women, in the NIH-AARP Health Study, during an average of 9 years of follow up in the cohort of 569,167 AARP members, aged 50-71. Dietary fiber intake was associated in this study with lower risk of death from cardiovascular disease, infections, and respiratory disease (and, in men only, cancer). Dietary fiber intake from grains was more highly correlated with improved health outcomes than dietary fiber intake from other sources (Arch Intern Med. 2011. 171. 1061-1068 and invited commentary 1069-1070).
Dietary fiber intake lowers serum cholesterol levels, lowers blood pressure, lowers blood sugar via improved insulin sensitivity, and promotes weight loss (Nutr Rev. 2009. 67. 188-205; Arch Intern Med. 2007. 167. 956-965; J Hypertens. 2005. 23. 475-481; Am J Clin Nutr, 1999. 69. 30-42).
Conditionally essential carbohydrates - humans can synthesize all of the carbohydrates we need to live, so no carbohydrates are essential in the diet. HOWEVER, the amount of certain sugars such as fucose, mannose, and xylose in the diet is often less than required for optimal biochemical functioning in many individuals, so these nutrients may be classified as conditionally essential. See ‘glycobiology’ just below for more information on the eight saccharides believed to play an important role in cell-to cell communication.
Glycemic index (www.glycemicindex.com)
Physiologically based measure of carbohydrate quality - a comparison of carbohydrates based on their immediate effect on blood glucose levels.
The glycemic index measures the rate of digestion.
Term first defined in 1981 (Jenkins DJ et al. Glycemic index of foods: a physiological basis for carbohydrate exchange. Am J Clin Nutr. 1981. 34. 362-366) and first glycemic index tables completed in 1995.
For most foods, the glycemic index correlates well with the insulin index of the food. Dairy products are an exception.
Measurement of the glycemic index
An amount of food containing 50 grams of carbohydrate is given to a volunteer to eat.
Blood glucose is measured at 15, 30, 45, 60, 90, and 120 minutes, and the area under the curve of time versus blood glucose is measured using a computer program.
The response is compared to that volunteer's response to 50 grams of glucose. The glycemic index of 50 grams of glucose is arbitrarily set at a value of 100.
The reference food is tested on several separate occasions and an average value is calculated for that individual.
The average glycemic index values in 8-10 individuals are then averaged to determine the glycemic index value of the food.
Note that some glycemic index charts use a 50-gram carbohydrate portion of white bread as the reference food with a value of 100 - it is possible to convert from the glucose scale to the white bread scale using the factor 0.7 (i.e. the glycemic index of white bread is 70 when the glycemic index of 50 grams of glucose is set at 100).
Note the glycemic index of a meal can be calculated as long as one has access to food composition tables to determine the amount of carbohydrate in each item in the meal - this calculation is demonstrated on page 36 of The New Glucose Revolution (2003). There is some controversy however about the validity of this measurement.
Note that the glycemic index of any given food may vary somewhat based on the ripeness, method of preparation used, growing conditions, number of times reheated.
Remember that the glycemic index is only one factor to consider in determining whether a food is healthy.
Factors which influence the glycemic index value of a food
Starch gelatinization - the less gelatinized (swollen) the starch, the lower the glycemic index. Al dente spaghetti has a lower glycemic index than overcooked spaghetti.
Physical entrapment - the fibrous coat around beans and seeds slows digestion because it takes more time for digestive enzymes to access the starch inside the fibrous coat.
High amylose to amylopectin ratio - amylose is a straight chain starch and absorbs less water than the branched chain amylopectin, and thus is digested more slowly.
Particle size - finely milled flours with a small particle size have a higher glycemic index because it is easier for water and enzymes to penetrate. Thus finely ground wheat fiber, such as is found in whole wheat bread, has a glycemic index similar to its white counterpart.
Viscosity of fiber - viscous fiber has a lower glycemic index.
Sugar - foods with sugar actually have a somewhat lower glycemic index because half of the sugar molecules are fructose.
Acidity - this slows down gastric emptying and is thus associated with a lower glycemic index.
Fat - this also slows gastric emptying.
Protein - this also slows gastric emptying.
The glycemic index is a clinically proven tool in its applications to diabetes and appetite control (but not coronary health).
A low glycemic index diet in diabetics leads to better control of blood sugar.
Consumption of high glycemic index foods leads to a transient high insulin level and this drives blood sugar down and increases appetite. Conversely, consumption of low glycemic index foods promotes weight loss in overweight people by delaying hunger pangs.
A low glycemic index diet reduces oxidative stress in the coronary arteries. In the Nurses' Health Study, those with a BMI over 23 who ate lots of high glycemic index foods had twice the rate of heart attack as those eating low glycemic index diets (The New Glucose Revolution. 2003. pg 224).
A meta-analysis of 8 prospective studies (n=220,050), with prespecified subgroup analysis, concludes that high dietary glycemic index and glycemic load significantly increased the risk of CHD in women but not in men, with more pronounced effects observed in overweight and obese patients (Am J Cardiol. 2012. 109. 1608-1613).
NEGATIVE trial – OmniCarb trial – this was a 5 week randomized crossover-controlled feeding trial of 163 overweight adults. In this trial, low glycemic index diets were not associated with improvements in insulin sensitivity, lipid levels, or systolic blood pressure, as compared with high glycemic index diets (JAMA. 2014. 312. 2531-2541 and editorial 2508-2509).
Glycemic load
Defined as the (glycemic index x grams of carbohydrate per serving) divided by 100.
This value is more helpful in predicting the effect of a particular food on blood glucose level.
For example, carrots have a relatively high glycemic index value of 47, but a low glycemic load value of 3 because there is relatively little carbohydrate in an average serving of carrots.
Protein
Old wisdom:
Protein from animal sources (i.e. meat and milk products) is preferable to protein from vegetable sources because vegetable protein is "incomplete," meaning that it does not contain all 8 essential amino acids.
White meat is preferable to red meat because the bad saturated fat is mostly in the skin rather than in the meat itself. Thus one can avoid excess saturated fat by eating skinless chicken or turkey.
New wisdom:
Incomplete vegetable protein is not a problem as long as one eats a variety of vegetables and grains and legumes over the course of a day, because the combination of these foods provides all 8 essential amino acids; the body does not actually need all 8 in the diet at the same meal.
Red meat provides us with excess arachidonic acid - this fat is converted to prostaglandins which promote inflammation in the body.
Fish is an excellent source of protein because the fat in the fish is a healthy omega 3 fat.
Legumes (beans, peas, lentils, soy products) are excellent sources of protein because they also have lots of fiber and phytochemicals.
Nuts and seeds are excellent sources of protein because they also have lots of fiber and minerals and monounsaturated fat.
Plant-based protein is less atherogenic than animal-based protein, and this seems to be a function of the arginine: lysine ratio, which is higher in plant-based protein.
Limitations of vegetable protein – not as easily digestible and totally lacking in the conditionally essential amino acid taurine (Shealy N. Life Beyond 100. 2005. pg 82).
History (National Geographic. June 2024. 100-103).
1772 - the element nitrogen was discovered, and believed to be an important element in the diet.
1838 - the existence of a compound called protein was proposed.
Protein requirements
Conventional wisdom - 0.6 - 0.8 grams protein/kg body weight per day, for all ages
Newer recommendations (controversial as per Review Article. Malnutrition in Adults. N Engl J Med. 2024. 391. 155-165) - 0.8 - 1.2 grams protein/kg body weight per day, for healthy middle aged and older adults, 1.2 - 1.5 rams protein/kg body weight per day in acutely ill patients or well-nourished patients after surgery
Amino acid classification (biochemical)
Acid, base, aliphatic, aromatic, based on side chain. Proline has a unique structure.
Branched chain amino acids (leucine, isoleucine, valine) – differ metabolically from all other amino acids.
Amino acids functions
Biochemical building blocks of protein - human proteins are composed of 20 biochemically distinct amino acids.
Cell-cell communication – connexins are amino acid chains which aggregate to form tunnel-like structures called connexons, which embed themselves in cell membranes and facilitate intercellular communication (Tanelian DL. Molecular Fitness: The Connexin Connection to Optimal Health).
Metabolic processes - creatine, carnitine, betaine, taurine, ornithine, and citrulline are amino acids which are not used as building blocks of protein, but are nonetheless important in human metabolism. Many essential amino acids are also important in metabolic processes.
Cysteine is a methyl donor in many biochemical pathways, including conversion of homocysteine to methionine.
Methionine and betaine are also methyl donors. Methylation of DNA is one of the mechanisms of controlling DNA expression.
Cysteine is a sulfur donor for one of the Phase II detoxification pathways.
Gycine, serine, taurine, and glutamine are important in Phase II detoxification.
Arginine is important in the synthesis of nitric oxide, which is important in endothelial function.
The branched chain amino acids can be oxidized completely in the mitochondria to provide energy.
Creatine and carnitine play key roles in energy metabolism.
Glutamine is an important nutrient for mucosal cells in the small bowel and also important in regulation of acid/base balance.
Glutamate is an excitatory neurotransmitter responsible for many neurological functions.
Essential amino acids
Eight of the 20 amino acids in human protein cannot be synthesized by humans, and thus must be consumed in the diet.
Additional amino acids such as taurine cannot be synthesized in quantities for optimum metabolic functioning (i.e. detoxification) - these amino acids are conditionally essential.
Glycoproteins and proteoglycans – important in cell to cell recognition and adhesion.
Glycoproteins contain 1-60% carbohydrate by weight, and have a sialic acid residue at the end of each polysaccharide.
Proteoglycans – 90-95% carbohydrate by weight, all of which is in the form of glycosaminoglycan chains, which are polysaccharides with at least one amino sugar and no sialic acid residues.
Biologically synthesized amino acids are all of the L form chemically, whereas chemically synthesized amino acids are of the combined DL form. The only D amino acids which the body can use are D-phenylalanine and D-methionine.
Nitrogen balance studies are the method of determining protein requirements - the flaw is that this method assumes that all amino acids are equal in terms of their importance to proper function in the body.
Unlike carbohydrates and fats which "burn clean" and break down into carbon, hydrogen, and oxygen; protein produces nitrogen when it is degraded, and this nitrogen must be metabolized by the liver into urea, then eliminated by the kidneys. Thus protein in the diet taxes the liver and kidneys. It is unclear whether this is harmful for a healthy person, but this biochemistry is the basis of recommendations for those with advanced kidney or liver disease to limit protein consumption.
Protein is a diuretic; the kidney must excrete lots of water in order to excrete urea.
Hormonal effects of protein – ingestion of protein stimulates release of glucagon from the liver. A delicate balance must be maintained between insulin and glucagon to maintain a normal blood sugar level and also to maintain the proper ratio of fat to glucose in the bloodstream in terms of the brain depending on glucose for energy needs while the body at rest derives most of its energy needs from fat.
Higher plant protein intake is associated with lower rates of hypertension in epidemiological studies.
Butter
A systematic review and meta-analysis shows that butter consumption is only weakly associated with mortality, is not associated with cardiovascular disease, and is inversely associated with incidence of diabetes. These conclusions analysis of 15 country-specific cohorts reporting on 636,151 participants (Pimpin L et al. PLoS One. Epub 6/29/16).
The butyric acid in butter, which is a short-chain fatty acid, plays a critical role from an energy standpoint in supporting the colonic epithelial cells.
Carrageenan (Townsend Letter. July 2011. 89-91 and June 2015. 40-41)
Carrageenans are sulfated polysaccharides obtained from red seaweeds.
Used by the food industry in the US since the 1950s, approved by the FDA as a food additive in 1961, and classified as a GRAS substance in foods.
Food grade carrageenan is used to improve the texture of foods, including dairy products, processed meats, soy milk, and infant formula (also used in cosmetics, pharmaceuticals, and toothpaste)
A two part review concluded that food grade carrageenan is safe (Crit Rev Toxicol. 2014. 4. 211-243 and 244-269).
However, safety concerns raised in the 1970s
Degraded carrageenan is a known carcinogen, and there is concern that gastric acid and acid contained in foods, as well as the effects of intestinal flora, may cause degradation of food-grade carrageenan into a carcinogen.
In animals, carrageenans can cause ulceration, polyps, colitis, and colorectal tumors (Environ Health Perspect. 2001. 109. 983-994).
Cheese
A type of fat in dairy called sphingolipids appears to benefit the heart. Butter has a low sphingolipid content compared with cheese and cream (Consumer Reports. August 2017. 19-20).
A meta-analysis of 18 prospective studies showed that high cheese intake is associated with a 13% reduced risk of stroke and an 8% decreased risk of coronary artery disease (deGeode J et al. J Am Heart Assoc. Epub 5/20/16).
A second meta-analysis of 31 prospective studies showed that high cheese intake is associated with a 13% reduced risk of stroke and an 18% decreased risk of coronary artery disease (Br J Nutr. 2016. 115. 737-750).
A 6 week crossover trial of 164 adults who ate an equal amount of dairy fat as either cheese or butter (cross over at 3 weeks) showed that LDL cholesterol increased more in the butter group than the cheese group (Fenney, E et al. 2018 study cited in Consumer Reports. November 2022. 36-39)
Cheese is a fermented food, and contains very little lactose (aged cheeses contain the least lactose, soft cheeses contain the most lactose)
Cholesterol (for more information, go to Home Page and click on “Cholesterol”)
Beware of deceptive labeling. Plant products such as cooking oils do not have cholesterol in them and never have had cholesterol in them. Despite a bold NO CHOLESTEROL label, they are often loaded with unhealthy fat.
The trans fat and saturated fat content of the diet, and possibly the amount of refined carbohydrate in the diet, is a much more important determinant of blood cholesterol levels than the cholesterol content of the diet (80% of total body cholesterol is synthesized in the liver).
NOTE that while the 2015 Dietary Guidelines for Americans no longer listed as a “nutrient of concern,” “this statement may be too general as it does not acknowledge conflicting findings in the literature regarding cardiovascular risk in certain populations. Current research indicates that dietary cholesterol may increase a subject’s risk of developing diabetes, increases a diabetic patient’s risk of cardiovascular disease, and may worsen coronary risk factors in subjects who are “hyper-responders” to dietary cholesterol.” (Am J Cardiol. 2015. 116. 1479-1480).
Chocolate (Altern Med Alert. 2005. 8. 138-142)
Historically, there has been a dual aspect to chocolate: chocolate as food and chocolate as medicine.
Historically chocolate has been primarily served as a beverage, including by the Olmecs, Mayans, and Aztecs.
Chocolate is produced from seeds of a tropical tree, Theobroma cacao.
A number of psychoactive compounds are found in chocolate
Biogenic amines (tyramine and phenylalanine) – sympathomimetic effects, stimulate dopamine release, MAY modulate mood.
Methylxanthines (theobromine, caffeine, theophylline) – competitive inhibitors of adenosine. Adenosine facilitates sleepiness.
Cannabinoid-like fatty acids (N-acetylethanolamine) – either acts at cannabinoid receptors in the brain or potentiates anandamide.
Chocolate cravings – research suggests that these are a function of the sensory experience of consuming chocolate and not pharmacological factors (Physiol Behav. 1994. 56. 419-422).
Chocolate is rich in a variety of minerals, especially copper, iron, magnesium, potassium, and zinc.
SAFETY - see subsection on ‘Risks’ at bottom of this section on ‘chocolate’
The ORAC value of dark chocolate is higher than that of blueberries, broccoli, and kale. Dark chocolate possesses a higher polypenol content per gram than wine, tea, or berries.
Dark chocolate and beneficial effects on biomarkers - these benefits are attributed to the flavonoid content of cocoa, specifically the polyphenol content, and more specifically to the compound (-)-epicatechin (Proc Natl Acad Sci USA. 2006. 103. 1024-1029).
Antioxidant effects (Am J Clin Nutr. 2001. 74. 576-602).
Reduced blood clotting (J Am Coll Nutr. 2001. 20. 436S-439S).
Improved HDL: LDL cholesterol ratio (Brit J Nutr. 2002. 88. 479-488).
Flavonol-rich cocoa has been shown to induce nitric-oxide dependent vasodilation (J Hypertens. 2003. 21. 2281-2286) and improve endothelial function (J Am Coll Nutr. 2004. 23. 197-204).
In a randomized trial in 25 male smokers, 40 grams of polyphenol-rich dark chocolate produced rapid improvement in endothelial and platelet function (Heart. 2006. 92. 119-120).
Dark chocolate consumption and potential health benefits.
In a 15 day crossover trial in 20 untreated patients with essential hypertension, 100 grams/day of dark chocolate was associated with an average 11.9 mm Hg drop in systolic BP and 8.5 mm Hg drop in diastolic BP by 24 hour ambulatory monitoring (Hypertension. 2005. 46. 398-405).
In a cohort of 470 elderly men who participated in the Zutphen Elderly Study, cocoa intake is inversely associated with blood pressure and 15 year cardiovascular and all-cause mortality (Arch Intern Med. 2006. 166. 411-417).
A meta-analysis of 5 RCTs involving a total of 173 subjects showed a drop in BP of 4.7/2.8 mm Hg associated with cocoa consumption. Median duration of studies was 2 weeks (Arch Intern Med. 2007. 167. 626-634).
An 18 week RCT in 44 adults who consumed a small quantity of dark chocolate per day (6.3 grams, containing 30 mg of polyphenols and consisting of 30 kcal) showed decreases in SBP of -2.9 (p<0.001) and DBP of -1.9 (p<0.001), without changes in weight. There was a significant increase in S-nitrosoglutathione (p<0.001), a marker of bioactive nitric oxide (JAMA. 2007. 298. 49-60).
In a 3 month trial of 102 patients, significant reductions were seen in mean ambulatory BP in the group which received 6 gm per day as well as 25 gm per day of dark chocolate (Am J Hypertens. 2010. 23. 694-700).
A meta-analysis of RCTs of chocolate, cocoa or cocoa flavan-3-ols identified 42 trials (n=1297) reported reductions in diastolic BP, reductions in fasting insulin, and improvements in flow mediated dilation (Am J Clin Nutr. 2012. 95. 740-751).
A meta-analysis of 16 studies with 344,453 participants reported that most studies found a significant reduction in CVD risk associated with increased chocolate consumption, as determined by food frequency questionnaires or self-report, such that the cardiovascular risk was 0.77 in the group with the highest chocolate consumption, as compared with the group with the lowest chocolate consumption. This study did not distinguish amongst white versus milk versus dark chocolate (Nutrition. 2018. 46. 103-114).
Read the food label and look for a cocoa content > 60%, and make sure that the label lists chocolate liquor, cacao, or cocoa as the first ingredient.
Flavanol levels currently are not listed on the label.
Heat and chemical reactions as cocoa is made tend to reduce flavanol content.
CocoaVia is a dark chocolate bar made by Mar’s Corp. and has a very high flavanol content and less fat than an ordinary candy bar – 100 mg of flavonoids and only 80 calories per 23 gram serving, compared with a typical chocolate bar with little flavonoids and 250 calories per 43 gram serving. Bars cost about $1 per very small bar and the bars are available in the healthy food section of grocery stores and also at www.cocoavia.com.
Stearic acid, a fat which represents approximately 30% of the fatty acids in chocolate is a saturated fat, but does not raise the serum cholesterol (Am J Clin Nutr. 1999. 70. 951-952).
Milk chocolate contains less cocoa than dark chocolate and more hydrogenated fats, milk, or corn syrup. White chocolate typically contains no cocoa at all.
Risks of chocolate consumption
Lead and cadmium contamination - levels are higher on average in dark chocolate bars as compared with milk chocolate bars
As You Sow (www.asyousow.org), a non-profit organization that pushes for corporate accountability, commissioned independent state-certified laboratories to measure lead and cadmium levels in in chocolate products sold in California, and 96 of 127 tested products had higher lead and/or cadmium levels than permitted by 1986 California legislation.
Contamination may arise from use of pesticides contaminated with heavy metals, phosphate fertilizers contaminated with heavy metals and/or sewage sludge contaminated with heavy metals.
As You Sow initiated a lawsuit against chocolate manufacturers in approximately 2019, based on these results (as per the below-cited Consumer Reports article).
Consumer Reports measured the amount of heavy metals in 28 brands of dark chocolate bars, and found high levels of lead and cadmium in 5 brands, high levels of lead or cadmium in an additional 18 brands, and acceptable amounts of lead and cadmium in only 5 of the 28 brands. Some of the brands with high levels were organic brands (Consumer Reports. February 2023. 34-41).
Studies indicated that the cacao plant takes up cadmium from the soil, and it concentrates inside the bean, the source of dark chocolate
Lead seems to contaminate the cacao bean after harvesting, as the bean lies on the ground and in the sun for days; lead is found in the outer shell of the bean and not the bean itself
Chocolate may exacerbate migraines and GERD.
Chocolate in large quantities can inhibit sulfation reactions, which are important for detoxification.
Coffee (Editorial. Wee CC. The Potential Health Benefit of Coffee. Ann Intern Med. 2022. 175. 1035-1036; Pollan, Michael. This is Your Mind on Plants. 2021)
Derived from the Coffea arabica plant.
Coffee and all-cause mortality (NOTE the strongest evidence of benefit comes from observational cohort studies, which are subject to confounding)
Coffee consumption is not associated with an increase in all-cause mortality, with a trend noted toward a decrease, based on 24 years of data in 41,736 men the Health Professionals Follow-up Study and 86,214 women in the Nurses’ Health Study. Coffee consumption in these cohorts was estimated by self report (Ann Intern Med. 2008. 148. 904-914).
Coffee consumption is inversely associated with total and cause-specific mortality during 5,148,760 years of follow up among 229,119 men and 173,141 women (aged 50-71) in the NIH-AARP Diet and Health Study (N Engl J Med. 2012. 366. 1891-1904).
Coffee consumption is associated with all-cause mortality in men and women younger than 55 years old, based on 17 year median follow up data in the Aerobics Center Longitudinal Study of 43,727 participants (Mayo Clin Proc. 2013. 88. 1066-1074).
Consumption of 4 - 5 cups of coffee daily associated with a lower all-cause mortality based on a 10-year data in a cohort of 90,317 healthy adults (Am J Epidemiol. 2015. 182. 1010-1022).
"Higher consumption of coffee was associated with a lower risk for death in African Americans, Japanese Americans, Latinos, and whites" based on data from the Multiethnic cohort study, a prospective study of 185, 855 individuals aged 45 - 75 (Ann Intern Med. 2017. 167. 228-235).
“Coffee consumption was associated with reduced risk for death from various causes. This relationship did not vary by country.” These conclusions are based on analysis of data in the EPIC prospective cohort study of 521,330 persons in 10 European countries (Ann Intern Med. 2017. 167. 236-247).
Sweeteners and all-cause mortality - moderate consumption of both sugar-sweetened and unsweetened coffee was associated with lower all-cause mortality, based on data in 171,616 recipients in the UK Biobank, with a median of 7 years of follow up. NOTE the added sugar per cup of sweetened coffee was approximately one teaspoon, which is approximately 4 grams. The association between artificially sweetened coffee and all-cause mortality was less consistent (Ann Intern Med. 2022. 175. 909-917).
Coffee and acute effects - in the CRAVE trial, a 14-day prospective, single-center RCT of 100 adults, coffee consumption as compared with no caffeine consumption was not associated with a statistically significant difference in the number of PACs or PVCs, was not associated with a difference in serum glucose levels, was associated with significantly increased number of daily steps (10,646 versus 9665) and was associated with a significant decrease in nightly sleep (397 minutes versus 432 minutes) [N Engl J Med. 2023. 388. 1092-1100].
Coffee and cancer - overall, coffee does NOT increase cancer risk (Eur J Cancer Prev. 2000. 9. 241-256).
Good data that it does not increase the risk of colon cancer (J NCI. 2005. 97. 282-292) or breast cancer; data more limited regarding the association of coffee consumption with other cancers.
May protect against endometrial cancer – in a prospective study of 60,634 women participating in the Swedish Mammography Cohort, during 17.6 years of follow up, women drinking 4 or more cups of coffee per day had a 25% lower risk of developing endometrial cancer. The reduction in risk was restricted to overweight and obese women (Int J Cancer. 2009. 125. 2413-2417).May protect against liver cancer. Compared to those who never consume coffee, liver cancer risk in those consuming 1-2 cups per day is 0.52, 3-4 cups per day is 0.48, and 5 or more cups per day is 0.24 (J NCI. 2005. 97. 293-300).
The publicized association of coffee consumption and increased risk of pancreatic cancer has not been confirmed by recent studies, as per 2006 Guidelines published by the American Cancer Society.
Coffee and cardiovascular disease – effect may vary based on genetic polymorphisms, or based on smoking status
An analysis of data in 44,005 men in the Health Professionals Follow-up Study and 88,488 women in the Nurses’ Health Study did NOT show an increased risk of CHD in coffee drinkers. Adjusting for other CHD risk factors, in men the risk was 1.0 for those who drank less than a cup of coffee per month, 1.02 for those who drank 1 cup daily, and 0.72 for those who drank 6 or more cups daily; in women the risk was 1.0 for those who drank less than a cup of coffee per month, 1.02 for those who drank 1 cup daily, and 0.87 for those who drank 6 or more cups daily (Circulation. 2006. 113. 2045-2053).
A prospective study in 127,212 subjects found that coffee consumption was unrelated to CAD risk in never smokers, but associated with a higher CAD risk in ex-smokers and current smokers (Am J Cardiol. 2008. 101. 825-827).
Chronic coffee consumption has a detrimental effect on aortic stiffness (Am J Clin Nutr. 2005. 81. 1307-1312). HOWEVER, in a study of 863 participants which determined caffeine consumption by measurement of 24 hour urinary caffeine and also 24 hour urine measurement of the caffeine metabolites paraxanthine, theophylline, and theobromine, higher coffee consumption was associated with decreased arterial stiffness, as measured by pulse pressure ( determined by 24 hour ambulatory BP monitoring) and pulse wave velocity (Mayo Clin Proc. 2018. 93. 586-596).
Consumption increases the risk of MI in slow metabolizers (variant CYP1A2 1F allele) but decreases the risk of MI in rapid metabolizers (CYP1A2 1A allele), based on a case control study in Costa Rica between 1994 and 2004, examining 2014 cases with first MI and 2014 controls (JAMA. 2006. 295. 1135-1141). Estimated that 50% of Caucasians have slow variant whereas only 14% of Japanese have the slow variant (Cancer Epidemiol Biomarkers Prev. 1994. 3. 413-421).
Acute caffeine ingestion (200 mg) significantly improves endothelial function in subjects with and without CAD, based on data from a cross-over RCT in 80 subjects in which endothelial function was assessed by brachial artery flow-mediated vasodilation (Am J Cardiol. 2011. 107.1255-1261).
Coffee and cholesterol - cafestol and kahweol are lipid compounds in boiled coffee which raise cholesterol; coffee filters (brewed coffee) remove most of these compounds (N Engl J Med. 1989 Nov 23;321(21):1432-7).
Coffee and depression – coffee consumption may be protective, based on data in 50,739 women in the Nurses’ Health Study (Arch Intern Med. 2011. 171. 1571-1578).
Coffee and diabetes – coffee is protective
Long term coffee consumption is associated with a statistically significantly lower risk of developing diabetes, with this association persisting independent of BMI, smoking status, and other dietary and lifestyle factors.
The relative risk in men consuming >6 cups per day is 0.46 and the relative risk for women consuming >6 cups per day is 0.71. The statistical association with prevention of diabetes was also present in both sexes for consumption of 4-5 cups/day (0.71 in men and 0.70 in women). This data is based on 41,934 men followed from 1986 to 1998 in the Health Professionals= Follow-up Study and 84,276 women followed from 1980-1998 in the Nurses= Health Study (Ann Intern Med. 2004. 140. 1-8).
Further data on 88,259 women in the Nurses’ Health Study II also showed that coffee even at mild-moderate intake is associated with a reduced risk of diabetes – RR = 0.87 for 1 cup daily, 0.58 for 2-3 cups daily, 0.53 for 4 or more cups daily (Diabetes Care. 2006. 29. 398-403).
A systematic review “supports the hypothesis that habitual coffee consumption is associated with a substantially lower risk of type II diabetes” (JAMA. 2005. 294. 97-104).
Lower risk of diabetes also seen in association with coffee consumption after 11 years of follow up in the cohort of 28,812 postmenopausal women in the Iowa Women’s Health Study (Arch Intern Med. 2006. 166. 1311-1316).
Coffee reduces the risk of diabetes in those with impaired glucose tolerance at baseline, based on a prospective study in 317 adults who were part of the Rancho Bernardo Study, and then developed impaired glucose tolerance. In this study, no dose-response relationship was observed (Diabetes Care. 2006. 29. 2385-2390).
Two meta-analyses report an inverse association between coffee consumption and type 2 diabetes (Arch Intern Med. 2009. 169. 2053-2063; Eur J Nutr. 2014. 53. 25-38).
Coffee is associated with a markedly lower risk of developing type 2 diabetes, comparing those who drink 4 or more cups daily with those to drink less than 1 cup daily, based on a prospective study of 4522 women with prior histories of gestational diabetes, followed for 26 years, from 1991-2017. Of note, study participants were predominantly white (Yang J, et al. Am J Clin Nutr. 2022).
Coffee and gallstones – in the Health Professionals Follow up Study in 46,008 men, long term consumption of 2-3 cups of coffee per day was associated with a 40% reduction in the risk for symptomatic gallstones; consumption of 4 cups of coffee per day was associated with a 45% reduction in risk (JAMA. 1999. 281. 2006-2012).
Coffee and hypertension – probably does not increase the risk (JAMA. 2005. 294. 2330-2335; Arch Intern Med. 2002. 162. 657-662).
Coffee and liver disease – coffee may be protective, based on a systematic review (Liver Int. 2014. 34. 495-504).
Coffee and neurological disease - coffee may be protective (Am J Epidemiol. 2015. 32. 2305-2315).
Coffee and osteoporosis- coffee may increase risk/conflicting data (Osteoporosis Int. 4/15/22).
Coffee and Parkinson’s disease – coffee may be protective (Ann Neurol. 2002. 52. 276-284; Eur J Clin Nutr. 2008. 62. 908-915).
Coffee and respiratory disease - coffee may be protective (N Engl J Med. 2012. 366. 1891-1904; Am J Epidemiol. 2015. 182. 1010-1022; Am J Clin Nutr. 2015. 101. 1029-1037).
Coffee and stroke
No increased risk in the Nurses’ Health Study (Circulation. 2009;119(8):1116-23).
22-25% decreased risk at 10 years of followup in the 34,670 women in the Swedish mammography cohort study (Stroke. 2011;42(4):908-12).
The health benefits of coffee are probably a function of phytonutrients in coffee, such as polyphenols, which reduce inflammation and oxidative stress.
Mechanism of action - caffeine is a molecule which binds to the same receptor as adenosine, and thus caffeine blocks adenosine from binding to its receptor. Adenosine levels gradually increase during the day, each day, and adenosine is a psychoactive compound that has hypnotic effects on the brain when it binds to its receptor.
Coffee and potential risks
May increase the risk of anxiety, cardiac arrhythmias, fibrocystic breast disease, headaches, infertility, osteoporosis, and urinary stress incontinence.
May cause depletion of calcium and magnesium.
Coffee contains approximately 85 mg caffeine per 8 ounce cup of drip-brewed cup.
For the average healthy adult, consumption of up to 400 mg daily of caffeine is safe, with a maximum of 300 mg daily recommended in pregnant women, based on a systematic review (Wikoff D et al. Food Chem Toxicol. 2017).
There are actually over 60 plant species which naturally contain caffeine – it is hypothesized that this is because caffeine is a natural pesticide (it is stored in specialized vacuoles because it is otherwise toxic to the plant).
Besides coffee and tea, other popular natural sources of caffeine include the kola nut, yerba mate, chocolate, and guarana.
Decaffeinated coffee – as per David Perlmutter, MD, chemical solvents are used in some cases to decrease the caffeine content of water – make sure to purchase water-decaffeinated coffee.
Dairy (see also 'butter' and ‘cheese’ above; ‘milk’ and ‘yogurt’ below)
Dairy consumption is NOT associated with weight gain (studies cited in Consumer Reports. November 2022. 36-39).
Full fat dairy consumption is associated with lower rates of diabetes and hypertension (studies cited in Consumer Reports. November 2022. 36-39).
The saturated fats in butter and other dairy products (but not cheese) have the most detrimental effect on LDL cholesterol, saturated fats in meat have a less detrimental effect, and saturated fats in chocolate have the least detrimental effect on LDL, as per Walter Willett (Eat, Drink, and Be Healthy. 2001).
Eggs
Old wisdom: eggs are bad because there are 200 mg of cholesterol in each egg yolk.
New wisdom: conflicting data
A systematic review and meta-analysis of 23 prospective studies with a median follow up of 12.28 years (N = 1,415,839) found that consumption of more than 1 egg per day was not associated with an increased risk of cardiovascular disease or stroke, and was associated with a decreased risk of coronary artery disease, as compared with consumption of no eggs or 1 egg per day (Am J Med. 2021. 134. 76-83).
Individual participant data from 6 prospective US cohorts (29,615 participants, median follow-up of 17.5 years) shows that each additional 300 mg of dietary cholesterol consumed per day is associated with a higher risk of cardiovascular disease (HR = 1.17) and all-cause mortality (HR = 1.18), and each additional half and egg consumed per day is associated with a higher risk of cardiovascular disease (HR = 1.06) and all-cause mortality (HR = 1.08). The relationship in this study between egg consumption and also dietary cholesterol consumption and CV disease and all-cause mortality, while modest in magnitude, was dose-dependent. This data is considered stronger than other data because the examination of individual participant data is thought to allow for stronger conclusions than examining cohorts alone, as cholesterol, animal fat and saturated fat often co-exist in food (JAMA. 2019. 321. 1081-1095 and editorial 1055-1056).
A meta-analysis of 14 studies found that those who consumed the most eggs had a 19% increased risk of cardiovascular disease and a 68% increased risk of diabetes, compared with those who consumed the least eggs (Li Y et al. Atherosclerosis. Epub 4/17/13).
Historically, a prospective study of the egg eating habits of 37,851 men in the Health Professionals Follow-up Study and 80,082 women in the Nurses’ Health Study showed no difference in risk of heart attack or stroke in those who ate up to one egg a day, compared to those who ate less than one egg a week (JAMA. 1999. 281. 1387-1394).
NOTE most individuals do not experience an increase in serum cholesterol in association with increased dietary intake of cholesterol.
Only 20-25% of the population will have a significant increase in serum cholesterol in response to an increase in dietary cholesterol. Possible mechanisms to explain the lack of rise in serum cholesterol in 75-80% include (1) a decrease in efficiency of cholesterol absorption and (2) increased conversion to and excretion of bile acids (N Engl J Med. 1991. 324. 912-913).
A 6 week RCT in 96 hypercholesterolemic men assigned to a low fat, low cholesterol diet containing no eggs versus a low fat diet containing 12 eggs per week found no significant differences at the end of the study in total, LDL, or HDL cholesterol (J Appl Nutr. 1993. 45. 73-84).
Whole eggs versus egg substitutes – in a randomized, single blind 12 week trial of 40 men and women with metabolic syndrome, significant reductions in plasma triglycerides (p < 0.05) and significant increases in HDL cholesterol levels (p < 0.05) were observed in both the group randomized to consume 3 whole eggs daily and in the group randomized to consume an equivalent amount of yolk-free egg substitute; there was a trend toward greater improvement in these values in the group randomized to consume whole eggs (Metabolism. 2013. 62. 400-410).
The fat in eggs is unsaturated fat.
Eggs are an excellent source of protein, phospholipids (i.e. phosphatidylcholine), and a multitude of vitamins and minerals.
There is scientific debate though regarding whether increased choline intake increases TMAO levels; the preponderance of data would suggest that dietary choline intake (including intake from supplements does not increase TMAO levels, based on a column (with extensive scientific citations) in a non peer-reviewed journal (Schor, Jacob ND. Townsend Letter. May 2020. 82-85).
Higher TMAO levels are associated with significantly increased risk of cardiovascular events and all-cause mortality, based on a meta-analysis of 11 prospective cohort studies (J Cell Mol Med. 2018. 22. 185-194).
Omega 3 enriched eggs are a way of supplementing omega 3 fat intake in the diet.
The downside to egg yolks is that they are rich in arachidonic acid, which is converted into pro-inflammatory eicosanoids.
Omega 3 enriched eggs probably contain less arachidonic acid.
Shelton is considered a reputable brand for organic eggs.
Fish (Ann Intern Med. 2004. 141. 977-980)
USDA estimated that fish consumption in the U.S. increased 50% between 1980 and 2000.
Researchers have found associations between fish consumption and reduced risk for asthma, cardiovascular disease, cardiovascular disease, dementia, diabetes, kidney disease, and stroke.
A systematic review of 24 studies (n = 714, 526) found that nonfried fish consumption is probably associated with a reduced risk of cardiovascular events; in contrast, fried fish consumption is probably associated with a increased risk of cardiovascular events (Am J Med. 2021. 134. 713-720).
Omega 3 fatty acid content of fish which are sustainably harvested and do not contain excessive mercury or PCBs (grams omega 3 per 3 ounce serving, as per Self Healing 8/08, pg 3) – Pacific herring (sardines) 1.6; Sablefish (black cod) 1.4; European anchovies 1.25; Spanish mackerel 1.25; wild sockeye salmon 0.95; farmed rainbow trout 0.84; Albacore tuna 0.8. See Consumer Reports 7/03 page 32 for a complete listing of other fish with lesser amounts of DHA (docosahexanoic acid) and EPA (eicosapentanoic acid).
Which fish to consume – issues include (1) mercury, (2) PCBs and dioxins, and (3) overharvesting
Fish which include no known risk to the consumer include anchovies, flounder, sole, and farmed clams, farmed rainbow trout, and farmed shrimp.
Fish which are fine to eat in moderation (once/week) include cod, farmed catfish, mahi, mahi, wild salmon, tilapia, and canned chunk tuna.
Fish to avoid include Chilean sea bass, Atlantic cod, Atlantic flounder and sole, grouper, farmed salmon and orange roughly, and red snapper.
RESOURCE: Monterey Bay Aquarium Seafood Watch lists options that are fished or farmed in ways that protect the environment. www.seafoodwatch.org
Mercury (specifically methylmercury) in fish is an issue:
Methylmercury is found naturally in the environment – it is estimated that roughly half of the methylmercury in the oceans has been there for millennium. Additional mercury is released through industrial practices such as the burning of industrial waste and fossil fuels. Fish are the main source of methylmercury exposure in humans.
Note that elemental mercury and inorganic mercury are dangerous to humans only when inhaled rather than ingested and thus problematic only for individuals with occupational exposure.
Note that the mercury in dental fillings is inorganic and thus may not be dangerous when swallowed.
Methylmercury is excreted in the feces; inorganic mercury is excreted in the urine.
Mercury is a neurotoxin, and pregnant women and young children are especially susceptible to its effects.
The U.S. EPA states that blood levels of mercury greater than 5 micrograms per liter or hair levels greater than 1 microgram per gram are potentially hazardous to the developing fetus, and these levels correlate with an exposure of 0.1 microgram/kilogram of body weight per day.
Blood levels over 50 micrograms per liter can cause tremor, difficulty with concentration, visual problems, and numbness and tingling in adults – these symptoms do not usually occur unless blood levels exceed 200 micrograms per liter.
A single 6 ounce serving of some fish can exceed the U.S. FDA recommendation that a 120 pound person consume no more than 38.5 micrograms of mercury per week.
Methylmercury reaches its highest levels in large, predatory fish and in bottom feeders (i.e. crab).
Fish highest in mercury in terms of mean values of methylmercury concentration in ppm are tilefish (1.45), swordfish (1.00), king mackerel (1.00), shark (0.96) [Perspective: Mercury and Health. N Engl J Med. 2002. 347. 1735-1736]. For reference purposes, sardines have 0.02 ppm (Consumer Reports. July 2004. 8).
Additional fish high in mercury (Consumer Reports. July 2023. Pages 26-27) include marlin, orange roughy, tilefish (Gulf of Mexico) and tuna (bigeye).
Fish moderate in mercury (Consumer Reports. July 2023. Pages 26-27) include and bluefish, buffalofish, carp, Chilean sea bass, grouper, halibut, mahi mahi, monkfish, sablefish (black cod), sheepshead, snapper, Spanish mackerel, striped bass (ocean), tilefish (Atlantic ocean), tuna (yellowfin and white, canned), weakfish/seatrout, and white croaker.
Fish low in mercury as per Natural Resources Defense Council and Consumer Reports October 2014 include bass, carp, catfish, cod, crab, crawfish (domestic), croaker (Atlantic), flounder, haddock, halibut, jacksmelt, lobster, mackerel (Atlantic), mahi mahi, monkfish, mullet, perch (freshwater), pollock, skate, snapper, trout, tuna (canned chunk light and skipjack), and weakfish.
Fish lowest in mercury as per Natural Resources Defense Council and Consumer Reports October 2014 include anchovies, butterfish, clam, hake, herring, oyster, perch (ocean), plaice, salmon, sardines, scallops, shad, shrimp, sole, squid, tilapia, whitefish, and whiting
NOTE: Chunk light tuna is generally much lower in mercury than albacore (white) tuna, but the FDA reports that 6% of light tuna samples contain at least as much methylmercury as the average in albacore.
There is scientific debate regarding the extent of the harmful effects of mercury in fish. The Seychelles Child Development Study, initially presented in 2005 found no mercury-related health/developmental problems in this population eating 10-12 seafood meals per week. A landmark 1997 study of Faroe islands people did show developmental problems in children with the highest mercury exposures, but the author attributed much of the risk to whale meat consumption rather than fish consumption. Whale meat does not have high selenium levels (see just below regarding selenium).
Selenium, which is plentiful in wild ocean fish, may cancel some of the harmful effects of mercury – mercury and selenium have a high binding affinity for one another and form a harmless selenium-mercury compound which is excreted. Theoretically, consuming 1-2 Brazil nuts (each Brazil nut contains approximately 100 mcg of selenium) with a portion of fish may protect against the mercury in the fish (Holistic Primary Care. Winter 2006. 4).
Measurement of mercury in blood and urine is inexpensive. A ‘provoked’ test may be more meaningful than a random test.
www.catchofthesea.com, www.tunalovers.com, and www.vitalchoice.com are web sites with information on brands of tuna lower in mercury, as per Dr. Andrew Weil (Self Healing. 9/05).
Polychlorinated biphenyls (PCBs) in fish are an issue:
Flame retardants, electrical equipment, pesticides, paints, varnished, and ink were made with PCBs until banned in 1979.
Environmental levels of PCBs dropped rapidly after the ban in 1979, but they continue to be released from sediment and are mostly insoluble in water, so they accumulate in fish living in polluted waters and some farmed fish.
Fish affected by PCBs in polluted waters vary by locality – check local state advisories at www.epa.gov/waterscience/fish/states.htm.
Accumulation in farmed fish is a function of PCB contaminated feed.
PCBs are thought to be carcinogenic and also appear to affect the central nervous system, cause immune suppression, and cardiovascular disease.
In a study published in 2004, it was reported that PCB levels in farmed salmon sold in the U.S. and Canada were approximately 30 ppb, which is 2-10 times the level in beef and 5 times the amount that EPA guidelines say is safe (Science. 2004. 303. 226-229). The authors concluded that more than 8 ounces of farmed salmon a month posed an “unacceptable cancer risk.” Industry in response to this study is changing the way farmed fish are fed.
Note that EPA guidelines set a much lower limit of acceptable intake of PCBs than does the WHO. One may eat 4-10 meals per month of farmed salmon per month (depending on where the salmon is raised) or 1 meal per day of wild salmon in terms of the WHO guideline for safe exposure to PCBs (Environ Health Perspectives. 2005. 113. 552-556).
Measurement of PCB levels is extremely expensive.
Environmental issues
Over-fishing has led to a decline of as much as 90% of the biomass of large predatory fish such as cod, haddock, and tuna.
Best choices of fish from an environmental perspective include wild Alaskan salmon and Pollack, wild Pacific halibut, herring, sardines, and farmed arctic char.
Fishing in terms of the size of the catch is unregulated in international waters.
“By-catch” which refers to the unwanted marine life caught in fishing nets, is a significant problem. An estimated 88 billion pounds of sea creatures are killed unnecessarily each year. The good news is that much by-catch can be prevented with changes in fishing techniques.
“Catch-sharing” is a potential solution to overfishing which at least in principle has the support of fishermen and conservationists.
Fish-farming is associated with multiple environmental and health issues
Many of the world’s fish farms are in Southeast Asia, or South America, where regulations are lax.
Fish farms sometimes destroy coastal marshlands and mangrove forests, which are habitats for many indigenous wild fish species.
Shrimp and salmon farms often use large quantities of antibiotics to protect the fish from infections.
Fish farms are big polluters – they generate tons of filth which diffuses out and adversely affects neighboring ecosystems.
Farmed fish may escape and breed with wild fish, resulting in hybrids that don’t reproduce well. Escaped farm fish may also carry parasites foreign host waters.
Large quantities of marine biomass are needed to feed the farmed fish.
Farmed fish may be fed vegetable oils and even grains, leading to a much lower omega 3 content.
Selenium content of farmed fish may be lower, and thus mercury exposure to farmed fish may be a more significant health issue.
Not all fisheries are eco-unfriendly though – US farmed tilapia and catfish are raised in an eco-friendly manner, as are farm raised mussels and clams.
Resources regarding information on toxins in fish and ecological concerns regarding overfishing (Self Healing. 5/06. 3)
Pocket Seafood Selector – lists fish as eco-best, eco-OK, or eco-worst based on average content of mercury and PCBs. www.oceansalive.org
Seafood Watch – categorizes seafood into green, yellow, and red categories based on sustainability. www.seafoodwatch.org
Guide to Ocean Friendly Seafood – color-coded key to evaluate abundance, fishing or farming methods, environmental concerns. www.blueocean.org
EPA information on toxins by waterway – www.epa.gov/waterscience/fish/states.htm
Labeling issues (Self Healing. 5/06. 3)
There are no USDA standards for ‘organic’ for seafood in 2009 (i.e. this term is not defined for fish from a regulatory standpoint).
As of 2005, it is required to label the country of origin for fish other than sushi, canned fish, and processed fish such as fish sticks (but compliance with this new law may be lax).
Farmed fish has been shown on occasion by independent testing to be erroneously labeled as wild fish.
Trusted label – Marine Stewardship Council’s seal, blue oval, that tells you you’re buying from an environmentally responsible fishery.
Fruits and Vegetables (see also section on Vegetables below)
A meta-analysis of 16 prospective studies, ranging from 4.6 to 26 years, found that fruit and vegetable intake was associated with a significantly lower risk of all-cause mortality, with a threshold of approximately 5 servings per day (BMJ. 2014. 349. g4490).
A meta-analysis of 95 prospective studies which included a total of 2 million participants showed that fruit and vegetable consumption was inversely associated with CV disease, cancer, and all-cause mortality in a dose-dependent manner, with maximum health benefit associated with consumption of 6-8 servings per day of fruit and vegetables (Int J Epidemiol. 2017. 46. 1029-1056).
Grains
Whole grains contain all three parts of the plant kernel – the outer layer of bran, the inner germ of the plant, and the largest part of the kernel, called the endosperm.
The bran provides fiber, B vitamins, iron, and antioxidants.
The germ provides B vitamins, vitamin E, minerals, and healthy fats.
The endosperm contains carbohydrates.
Refined grains are stripped of the nutritious bran and germ during milling, leaving behind the carbohydrate-rich endosperm.
Enriched grains are refined grains to which the manufacturer has added back some of the vitamins and minerals lost during refinement.
The USDA as of the 2005 Dietary Guidelines specifically recommends 3 ounces of whole grains per day.
Note that when whole grains are ground to flour (i.e. whole wheat flour) the glycemic index can be high even though it is a whole grain product.
Arsenic – see “rice” just below
Whole grain consumption and health outcomes - a meta-analysis of 14 prospective cohort studies (n=786,076) found that higher consumption of whole grains is associated with a lower risk for total mortality, cardiovascular mortality and cancer mortality (Circulation. 2016. 133. 2370-2380).
Food labels and color
Foods that are mostly or completely whole grain list the word “whole” with the first ingredient. Ingredients are listed in descending order by weight.
BEWARE that healthful-sounding words like ‘multi-grain’ and ‘seven-grain’ are marketing terms and do not mean the product is whole grain.
BEWARE that brown-colored bread is often is often refined white bread with added caramel coloring.
BEWARE that not all foods made with whole grains are good sources of fiber, so check the fiber grams on the label too.
Wheat is a highly hybridized grain; many health authorities recommend minimizing consumption of all wheat products.
Types of grains
Amaranth – cultivated by the Aztecs, gluten free, high fiber content and complete amino acid profile, mild, slightly sweet taste. Traditionally eaten as breakfast porridge.
Barley –high in beta-glucans, which lower cholesterol; tastes similar to oats, contains gluten. Whole-grain hulled barley has more fiber than any other whole grain.
Buckwheat – native to southeast Asia, gluten free
Bulgur – nutty-tasting grain made from cracked wheat kernels, quick cooking time. Contains gluten
Corn – gluten free, grain as well as a vegetable, has the highest level of antioxidants of any grain
Farro – domesticated in the Near East, resembles barley
Kamut – chewy and nutty tasting, contains gluten
Millet – staple in Africa, China, and India; gluten free, alkaline, buttery flavor similar to rice
Oats - gluten free, high beta glucan content facilitates cholesterol-lowering
Quinoa – grown in Andean region of South America, gluten free, quick cooking time, nutty tasting, complete amino acid profile. Rinse to reduce bitter taste. Technically a tiny seed and not a grain.
Rice - gluten free. Arsenic contamination is an issue. Rinse raw rice prior to cooking, use a ratio of 6 cups of rice to 1 cup of water for cooking, and drain the excess water afterward – traditional method of cooking in Asia. Some loss of nutrients, but this method removes about 30% of rice’s inorganic arsenic content. NOTE as per Consumer Reports testing (Consumer Reports on Health. February 2015. Page 2), white basmati rice, brown basmati rice, and sushi rice have ½ - 1/3 arsenic as compared with other types of rice.
Rye - contains gluten
Seminola - contains gluten
Sorghum – popular in Africa, gluten free, high in fiber
Spelt - contains gluten
Teff – tiny grain, gluten free, indigenous to Ethiopia and Eritrea, low glycemic index and contains all 9 essential amino acids
Tricale - contains gluten
NOTE that grain-free cereals can be healthy as some substitute nuts and seeds for grains, but beware of added sugars in some grain free cereals, and be aware that whole grains in general are a staple of optimum nutrition (Consumer Reports on Health. January, 2023).
Meat
Meat consumption and associations with disease and mortality
Data from two prospective cohorts, the Nurses’ Health Study (83,644 women followed from 1980-2008) and Health Professionals Follow-up Study (37,698 men followed from 1986-2008) shows that “red meat consumption is associated with an increased risk of total, CVD, and cancer mortality. Substitution of other healthy protein sources for red meat is associated with a lower mortality risk.” Questionnaires were administered biennially in both of these studies (Arch Intern Med. 2012. 172. 555-563).
Data from 3 cohorts of US adults and an updated meta-analysis concluded that red meat consumption is associated with an increased risk of type 2 diabetes (Am J Clin Nutr. 2011. 94. 1088-1096).
A meta-analysis of data from cohort studies concludes that consumption of red meat and processed meat increase the risk of colon cancer. Gram for gram, processed meat consumption is associated with double the risk of colon cancer, as compared with red meat consumption (PLoS One. 2011. 6. e20456).
A large cohort study (over 500,000 people) with 10 years of follow up showed that higher intake of total red meat and total processed meat was associated with higher mortality (Arch Intern Med. 2009. 169. 562-571).
HOWEVER, Guideline Recommendations from the Nutritional Recommendations (NutriRECS) International Consortium are “that adults continue current unprocessed red meat consumption (weak recommendation, low certainty evidence) … (and) continue current processed red meat consumption (weak recommendation, low certainty evidence)” [Clinical Guideline. Ann Intern Med. 2019. 171. 756-764].
This conclusion that there is NOT high-quality data to support health harms of meat or processed meat consumption is based upon 4 systematic reviews of randomized, controlled trials and observational trials by an independent group with clinical and nutritional content expertise and skilled in the methodology of systematic reviews and practice guidelines. The group of 14 included 3 community members and for all members there were strict criteria concerning conflicts of interest.
The development of this guideline adheres to the Institute of Medicine and GRADE working group standards.
A systematic review and meta-analysis of cohort studies with at least 1000 participants (55 cohorts and 61 articles with over 4 million participants) found that “The magnitude of the association between red and processed meat consumption and all-cause mortality and adverse cardiovascular outcomes is very small, and the evidence is of low certainty” (Ann Intern Med. 2019. 171. 703-710).
A systematic review and meta-analysis of cohort studies with at least 1000 participants (56 cohorts and 118 articles with over 6 million participants) found that “The possible absolute effects of red and processed meat consumption on cancer mortality and incidence are very small, and the certainty of the evidence is low to very low” (Ann Intern Med. 2019. 171. 711-720).
A systematic review of randomized trials (12 eligible trials, with a single trial [ Women’s Health Initiative] enrolling 48,835 women providing the most credible evidence) reported “Low to very low certainty evidence suggests that diets restricted in red meat may have little or no effect on major cardiometabolic outcomes and cancer mortality and incidence” (Ann Intern Med. 2019. 171. 721-731).
A systematic review and meta-analysis of cohort studies with at least 1000 participants (more than 400,000 patients) reported “Low to very low certainty evidence suggests that dietary patterns with less red and processed meat intake may result in very small reductions in adverse cardiometabolic and cancer outcomes” (Ann Intern Med. 2019. 171. 732-741).
A mixed methods systematic review concluded that “Low-certainty evidence suggests that omnivores are attached to meat and are unwilling to change this behavior when faced with potentially undesirable health effects” (Ann Intern Med. 2019. 171. 742-755).
Relevant issues aside from the nutritional value of the meat include:
Antibiotics given to the animals to promote growth.
Bacterial contamination of ground beef – fresh oregano, 1 tablespoon per pound of burger meat or meat loaf, has an antibacterial effect.
Humanity of the conditions in which the animals are raised.
The type of food given to the animals (i.e. corn and soy versus grass) – see Time 6/12/06 pp. 76-78
Saturated fat content of the meat is lower in grass fed animals (Asia Pac J Clin Nutr. 2006. 15. 21-29).
Acid resistant E coli bacteria much more common in the stomach of cows fed corn and soy, and this bacteria can spread from the feces to the meat and cause human disease in those who consume the meat (if not detected by USDA inspections).
Stomach ulcers and liver abscesses much more common in cows fed a grain-based (corn, soy) diet.
Omega 3 fatty acid content, CLA content, and vitamin A and vitamin E content are slightly higher in grass fed animals (J Anim Sci. 2002. 80. 1556-1563; Asia Pac J Clin Nutr. 2003.12. S38). The explanation for this is as follows: The first chamber of a grass-fed cow's stomach has a pH of 7, and is colonized by bacteria that synthesize high levels of omega 3 fats and CLA. The first chamber of the stomach of a cow that eats grains is much more acidic, and the acidic pH fosters the growth of bacteria which synthesize far more omega 6 fats than omega 3 fats and CLA. The omega 6: omega 3 content of the meat of a grass fed cow or lamb is similar to that of salmon, 1.5 to 1, whereas the omega 6: omega 3 content of the meat of a grain fed cow is 7 to 1 (Time. 8/30/10. 30-40).
Concentration of environmental toxins at the top of the food chain.
Utilization of world resources to raise cattle versus planting vegetables and grains.
Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) are produced by cooking meat.
These cause cancer in lab animals.
Cooking temperatures in excess of 300 degrees Fahrenheit, cooking times in excess of 2 minutes, charring of food, and frying, grilling, broiling, or BBQ all increase production of these compounds.
Minimize production by choosing lean meats, trimming fats, using marinades (combination of vinegar, citrus juice, herbs, spices, and olive oil), microwaving briefly before cooking, and cooking small portions to minimize grill time, cooking with lower temperatures and turn the meat frequently.
BEWARE of deceptive labeling (Consumer Reports. 6/04. 5)
Hormone free and antibiotic free in beef by regulation means only that no hormones or antibiotics have been administered within 90 days of slaughter.
The USDA in 2007 required that ‘grass-fed’ cows obtain 100% of their daily calories from grass; prior to this the USDA did not verify the accuracy of this description. Look for “USDA-verified grass-fed” beef.
‘Certified organic’ or ‘certified biodynamic’ are terms verified by the USDA which indicate that the animals are fed no animal parts.
Meat when metabolized creates acidic byproducts and some experts hypothesize that slight increases in acidity in the body even when within normal range are harmful.
Arachidonic acid in meat increases production of pro-inflammatory eicosanoids in the body; grass fed beef probably has less arachidonic acid.
Meat consumption does incease TMAO levels, and higher TMAO levels are associated with significantly increased risk of cardiovascular events and all-cause mortality, based on a meta-analysis of 11 prospective cohort studies (J Cell Mol Med. 2018. 22. 185-194).
Coleman, Manning, B3R, and New Zealand beef are considered reputable brands.
Lean meat by definition contains less than 3 grams of fat per ounce.
Bison (Time. 3/26/07)
Bison do not tolerate confinement well, so they must be allowed for most of their lives to roam on the range and eat grass, and consequently they are leaner, with less saturated fat. They also likely have a higher content of omega 3 fat than grain fed cows.
Some bison are corralled and fed grain just prior to slaughter, in order to make the meat richer – this type of bison meat is not as healthy.
The USDA has developed regulations for shooting bison in the field, and this is considered more humane than killing them in a slaughter house.
Plant-based meat - became popular as an alternative to meat in approximately 2020
These products are produced solely from plant-derived sources, namely pea and soy; they are highly processed.
Brands (in 2023) include Beyond, Impossible, Good Catch, Lightlife, No Evil, and Gardein
Vegan meets in 2023 represent approximately 10% of the global meat industry; they generated an estimated $800 million globally in 2020.
Tissue cultured meats (Goldman, Erik. Holistic Primary Care. Summer 2023)
The cultured meat industry uses animal-derived cell samples to grow large quantities of tissue in bioreactors
This process, which involves harvesting muscle cells from desired animals and then growing them in nutrient-packed liquid media, was first developed in 2013 in The Netherlands
The entire cycle takes approximately 14 days, with an end product which is raw tissue that at a cellular level is the same as the traditional meat procured from slaughter animals
Regulatory in the US - in 2023, the FDA approved the US based company formally known as Memphis Meets and now known as Upside Foods to bring its tissue-cultured chicken to market once the companies facilities and products have been inspected and cleared by the US Department of Agriculture
History
Singapore in 2020 was the first country to approve sale of cultured meat, and in 2023 as a major hub for the cultured meat industry
Cultured meat startup companies have emerged around the world
Benefits of cultured meat
Less cruelty to animals
Less environmental impact than raising conventional livestock
Antibiotic free
If cost can be reduced over time, this will increase international access to nutritious protein
Challenges/concerns in 2023
Dependence of the process on fetal bovine serum
Cost
Highly processed
Corporate control of food
Public acceptance
Religious and ethical questions
Milk (and see separate sections above on ‘butter’ and ‘dairy’)
Review Articles
Goldberg JP, Folta SC. Milk: can a ‘good’ food be so bad? Pediatrics. 2000. 110. 826-832.
King JC. The milk debate (editorial). Arch Intern Med. 2005. 165. 975-976.
Willett, WC and Ludwig DS. Milk and Health. N Engl J Med. 2020. 382. 644-654
2005 dietary guidelines recommend consuming “3 cups per day of fat-free or low-fat milk or equivalent milk products.” These guidelines are unchanged in 2020, and addressed in the above-cited review article on milk and health.
Fat content – mostly saturated fat.
NOTE 2% low fat milk is 2% fat by weight, 35% fat by calories.
When milk is made into cheese the fat is concentrated so the fat content of cheese is often 50-70%.
Ingredients in milk – milk is a complex colloidal dispersion of fat globules (3.9%), and protein (3.5% casein and whey) in an aqueous solution (87%) of lactose (4.9%), minerals, and other minor constituents (0.7%).
Micronutrients
Milk is a good source of calcium, magnesium, phosphorus, potassium, zinc, and vitamins A, B1, B2, B6, B12, and D.
The “Price Factor” (a fat soluble catalyst that encourages optimal assimilation of vitamins and minerals) is present in milk from cows which graze, absent when cows are fed soy or cottonseed
Sugar – lactose.
Estimated that 25% of Americans have lactose intolerance (Pediatrics. 2000. 110. 826-832), and thus may experience bloating, flatulence, and abdominal pain with milk or dairy consumption. Many of these individuals though can tolerate 1-2 cups of milk if spaced throughout the day.
Goat's milk may be easier for some to digest than cow's milk.
Protein – the quality of the protein in milk (i.e. essential amino acid composition) is good.
Whey rarely causes symptoms, and is insulinotropic (Am J Clin Nutr. 2004. 80. 1246-1253) and a potent stimulus for secretion of glucagonlike peptide (Arch Intern Med. 2005. 165. 975-976).
Casein (which is also present in yogurt) based on anecdotes can increase mucous production and aggravate asthma, bronchitis, sinusitis, allergies, and autoimmune problems (lupus, multiple sclerosis, rheumatoid arthritis) in some people.
Fats
Mostly saturated fat.
Contains CLA (amount is 500% higher in exclusively grass-fed cows) which may assist with weight loss and prevent cancer.
NOTE 2% low fat milk is 2% fat by weight, 35% fat by calories.
NOTE when milk is made into cheese the fat is concentrated so the fat content of cheese is often 50-70%.
Enzymes – pasteurization destroys many of the digestive enzymes. The enzyme xanthine oxidase in homogenized milk is surrounded by a protective coating of fat molecules, allowing it to escape degradation by digestive juices and to be absorbed into the bloodstream intact. This substance may promote atherosclerosis (Gaby A. Preventing and Reversing Osteoporosis. 1994. Pg. 117).
Hormones
Cows have been bread to produce higher levels of IGF-I (insulin-like growth factor I) because IGF-I stimulates increased milk production (J Anim Sci. 2012. 90. 2193-2200). IGF-I mediates growth hormone action, such that increased IGF-I is associated with higher levels of growth hormone.
Modern dairy farming involves milking the cows when they are pregnant, because pregnant cows produce more milk than nonpregnant cows, and this practice is associated with higher levels of estrogen and progesterone in milk, which in turn may increase risk of premature sexual development and also breast cancer.
15-30% of cows in the U.S. are injected recombinant bovine growth hormone in order to increase output of milk. These cows are more susceptible to infections and thus receive more antibiotics. Milk from these cows may have higher IGF-1 levels, and this protein may pass into the bloodstream. IGF-1 may increase the risk of breast, colon, and prostate cancer. Organic milk comes from cows which do not receive rBGH and many other countries have banned rBGH because of the adverse effects on cows who are administered this hormone (Self Healing. 1/05)
Antibiotics - “Milk is allowed to contain a certain concentration of 80 different antibiotics – all used on dairy cows to prevent udder infections. With every glassful, people swallow a minute amount of several antibiotics.” (Newsweek. 3/28/94. 47-51).
A2 versus A1 milk and beta-casomorphin-7 (Cross, J. Townsend Letter. February/March 2015. 77-82).
Milk that contains A1 beta-casein is known as “A1 milk;” milk that does not contain this beta-casein is known as “A2 milk.”
Originally all milk was A2, until a mutation affecting Holstein cattle occurred 8000 years ago.
Currently, cows in United States, New Zealand, Australia, and many other Western countries produce A1 milk.
Herds in much of Asia, Africa, and much of southern Europe produce A2 milk.
Human milk is A2 milk.
Goat milk, yak milk, and most sheep milk is A2 milk.
Diseases such as diabetes type 1 and cardiovascular disease are linked to a tiny fragment formed during the digestion of A1 beta-casein – this fragment is named BCM-7.
Epidemiologic evidence links A1 beta-casein with ischemic heart disease, and pharmacologic evidence links A1 beta-casein to oxidation of LDL cholesterol.
Epidemiologic evidence across 20 countries links A1 beta-casein with incidence of type I diabetes.
Anecdotally, in some with milk intolerance, the intolerance resolves when they switch from A1 milk to A2 milk.
Consumers can request A2 milk; New Zealand labels A2 milk in the supermarket.
Benefits (possible) associated with milk and dairy consumption
All-cause mortality
Consumption of fermented dairy products (cheese and yogurt) is associated with lower all-cause mortality (Am J Clin Nutr. 2017. 105. 1502-1511).
HOWEVER, a dose-response meta-analysis of 29 prospective cohort studies failed to show a benefit of whole milk, low-fat milk, or dairy consumption on total mortality (Eur J Epidemiol. 2017. 32. 269-287).
Breast cancer
Premenopausal – reduced risk seen (J Natl Cancer Inst. 2002. 94. 1301-1311).
Postmenopausal – reduced risk seen (Cancer Epidemiol Biomarkers Prev. 2005. 14. 2898-2904).
Colon cancer – reduced risk seen (Cancer Causes Control. 2000. 11. 459-466).
Coronary artery disease – reduced risk seen in some studies (Am J Epidemiol. 1999. 149. 151-161; J Epidemiol Community Health. 2001. 55. 379-382), BUT a dose-response meta-analysis of prospective cohort studies failed to show a benefit of whole milk or low-fat milk on the incidence or mortality from heart disease (Eur J Epidemiol. 2017. 32. 269-287).
DM Type II
Reduced risk seen in men in association with dairy consumption, especially low-fat dairy consumption, based on prospective data on 41,254 male participants in the Health Professionals Follow-up Study with no history of diabetes, cardiovascular disease or cancer at baseline (Arch Intern Med. 2005. 165. 997-1003).
HOWEVER, no benefit seen in an updated meta-analysis (BMC Med. 2014. 12. 215)
Gout- reduced risk seen in men (N Engl J Med. 2004. 350. 1093-1103).
Hypertension – favorable effects seen in prospective studies (Hypertension. 1996. 27. 1065-1072; Circulation. 1989. 80. 1320-1327).
Insulin resistance – strong inverse relationship seen between dairy intake and risk of insulin resistance in overweight young adults in the CARDIA study (JAMA. 2002. 287. 2081-2089).
Obesity – see ‘weight loss’ just below
Stroke – reduced risk seen in one study (Stroke. 1996. 27. 813-818), BUT a dose-response meta-analysis of prospective cohort studies failed to show a benefit of whole milk or low-fat milk on the incidence or mortality from stroke (Eur J Epidemiol. 2017. 32. 269-287).
Weight loss - conflicting data
Three small published studies show that milk facilitates weight loss – these studies were funded by the National Dairy Council, conducted by Michael Zemel, PhD, and have methodological flaws.
No benefit seen in 51,529 men ages 40-75 in the Harvard Health Professional Follow-up Study, when analysis is adjusted for possible confounders (Am J Clin Nutr. 2006. 83. 559-566).
A meta-analysis of 29 RCTs investigating the effects of dairy products on body weight showed no overall effects of milk or other dairy foods on body weight (Am J Clin Nutr. 2012. 96. 735-747).
NOTE on 6/28/05 PCRM (Physicians Committee for Responsible Medicine) filed lawsuits to stop an advertising campaign claiming that milk facilitates weight loss, and in 5/07 the FTC announced that it was banning the advertisements promoting dairy consumption as a means of achieving weight loss.
Harms associated with milk and dairy consumption (and see just above ‘Ingredients in milk’)
DM Type I – NOTE however that the issue may be an enhanced immunity to proteins in general and proteins in wheat and soy appear to be more potent diabetogens than those found in milk (Arch Intern Med. 2005. 165. 975-976).
Infertility – increased risk of infertility associated with two or more servings of low fat dairy per day, based upon data from 18,555 premenopausal women in the Nurses’ Health Study II (Hum Reprod. 2007. 22. 1340-1347).
Osteoporotic fractures
Despite the advertisements for milk for osteoporosis prevention, epidemiologic and cross cultural data actually show a positive correlation between intake of milk products and osteoporotic fractures (Hippocrates. July/August 1999. 53-55).
A 12 year Harvard study which prospectively tracked the dietary intake and medical histories of 77,761 women showed an increased risk of osteoporotic fractures associated with increased milk consumption (Am J Pub Health. 1997. 87. 992-997).
Cross cultural data show a positive correlation between intake of milk products and hip fractures (Am J Clin Nutr. 2001. 74. 571-573).
In a review of 37 studies of dairy or unsupplemented dietary calcium intake in children, adolescents, and young adults, 27 studies found no relationship between dairy or dietary calcium intake and measures of bone health (Pediatrics. 2005. 115. 736-743).
High milk intake is associated with an increased risk of osteoporotic fractures among women and no risk reduction in men; based on data in two large Swedish cohorts, one including 61,433 women aged 39-74 at baseline, and the second including 45,339 men aged 45-79 at baseline. Both groups completed food frequency questionnaires. In addition, high milk intake was associated with increased levels of biomarkers of oxidative stress and inflammation (BMJ. 2014. 349. 7981).
Ovarian cancer – increased risk, based on a meta-analysis (Int J Cancer. 2005). Individual studies which showed an increased risk include the Harvard Nurses’ Health Study (Int J Cancer. 2004) and the Iowa Women’s Health Study (Am J Epidemiol. 1999).
Parkinson’s – increased risk based on data in 388 men and women with Parkinson’s participating in the ACS Cancer Prevention Study II (Am J Epidemiol. 2007. 165. 998-1006).
Prostate cancer
In the Physicians’ Health Study in 20,885 male physicians, data at 11 years of follow-up showed a relative risk of prostate cancer of 1.34 in those who consume > 2.5 servings of dairy products compared to those who consume 0.5 servings per day (Am J Clin Nutr. 2001. 74. 549-554).
A review of 14 case-control studies and 9 cohort studies concludes that dairy intake “is one of the most consistent dietary predictors for prostate cancer in the published literature (Epidemiol Rev. 2001. 23. 87-92).
A meta-analysis of 12 studies found that men with the highest intake of dairy and calcium had a higher risk of prostate cancer (J Natl Cancer Inst. 2005. 97. 1768-1777).
Analysis of 2776 men in the French SU.VI.MAX Study showed a higher risk of prostate cancer in those with higher dairy and calcium intake. A harmful effect of yogurt consumption on prostate cancer risk was identified in this study (Br J Nutr. 2006. 95. 539-545).
In a prospective study in a cohort of 27,028 smokers age 50-69 (ATBC study), increased dairy intake and increased dietary calcium intake was associated with an increased risk of prostate cancer at 17 years of follow-up. Of note, when dietary calcium or calcium from dairy products was controlled for, the association between total dairy intake and increased risk of prostate cancer became statistically nonsignificant (Int J Cancer. 2007. 120. 2466-2473).
Increased risk reported in a systematic review and meta-analysis of cohort studies (Am J Clin Nutr. 2015. 101. 87-117).
NOTE that plant-based creamers are generally acceptable alternatives to half and half but not necessarily healthier, as they often have added sugar and added vegetable oil and emulsifiers (such as carageenan, which in some individuals might trigger GI symptoms) [Consumer Reports on Health. January, 2023].
Mushrooms
Mushrooms are saprophytes; they derive their energy from decomposing plant material and do not require sunlight.
Mushrooms can synthesize vitamin D2 from ergosterol, when mushrooms are exposed to UV-B light (UV-B does not penetrate glass windows).
Mushrooms boost and balance immune system function - compounds responsible for immunomodulation include beta-glucans, sterols, terpenes, terpenoids, and fungal immunomodulatory proteins (FIPs).
Mushrooms enhance gut microbial diversity.
Mushrooms increase production of salivary secretory IgA.
Mushrooms have compounds with anti-viral effects.
Mushrooms are potent antioxidants
Glutathione and ergothioneine are powerful antioxidants in mushrooms, and cooking does not seem to inactivate these compounds.
Ergothioneine is a unique sulfur-containing amino acid not synthesized in humans.
Mushrooms contain trace minerals (copper, selenium, zinc) which boost immune system function.
Culinary considerations
Raw mushrooms contain a mild toxin, agaratine, which is destroyed by heat, so best to cook mushrooms.
Options for cooking include saute, grilling, roasting.
Nuts (and for more information on nuts, go to the page of this site on “Prevention of MI” and scroll to the section on nuts for primary prevention)
Nuts in general are good sources of protein, fiber, monounsaturated fat, plant sterols, and minerals.
Tree nuts (almonds, Brazil nuts, cashews, hazel nuts, macadamia nuts, pecans, pine nuts, pistachios, and walnuts).
All are rich in monounsaturated fat, which is "good fat." Brazil nuts, cashews, macadamia nuts, and pine nuts though do have higher saturated fat content than almonds, hazel nuts, pecans, pistachios, and walnuts.
Almonds are an excellent source of vitamin E. NOTE almonds must be pasteurized in the U.S. (as of 9/07) based on outbreaks of Salmonella traced to raw almonds. Chemical pasteurization in the U.S. may involve the use of propylene oxide, a potential carcinogen. Choosing organic varieties allows one to avoid almonds pasteurized with this chemical (Self Healing. 1/08. Pgs 6-7).
Brazil nuts are an excellent source of selenium.
Hazelnuts are an excellent source of copper and manganese.
Pine nuts are an excellent source of vitamin K.
Pistachios are an excellent source of gamma tocopherol (a form of vitamin E), thiamine and potassium.
Walnuts are an excellent source of alpha linolenic acid (omega 3) and antioxidants
The FDA approved a qualified health claim in approximately 2007 for almonds, hazel nuts, pecans, pistachios, and walnuts, stating that there is supportive data that consumption of 1.5 ounces (45 grams) per day reduces the risk of heart disease.
Peanuts (actually legumes and not true nuts) are slightly less healthy overall than many other nuts in terms of having more saturated fat; aflatoxin contamination of peanuts is believed to affect only nuts grown and stored in Africa.
Soy nuts are an excellent source of soy protein, which is associated with cardio protective effects.
Epidemiologic data – in general, epidemiologic studies have shown that tree nut consumption decreases the rates of coronary disease events, sudden cardiac death, diabetes, and gallstones. A variety of types of clinical studies have been conducted using almonds, hazelnuts, macadamia nuts, pecans, pistachios, and walnuts (Alt Med Alert. 2007. 10. 17-21).
Epidemiologic studies show an inverse correlation between nut consumption and BMI (Am J Clin Nutr. 2003. 78. 647S-650S).
Epidemiologic studies show an inverse relationship between intake of both almonds and walnuts and the risk of heart disease. The Seventh Day Adventist Study which had more than 31,000 participants found that those who reported eating nuts more than 4 times per week had a 50% lower risk of CAD than those who rarely ate nuts (Arch Intern Med. 1992. 152. 1416-1424). Similar results were seen in the Nurses’ Health Study, with a 35% lower risk of CAD (BMJ. 1998. 17. 1341-1345).
A systematic review of 23 published studies of the effect of nut consumption on lipid profiles found that nut consumption is associated with improvement in blood lipid values. The investigators suggest intake of 50-100 grams of nuts five days per week (J Nutr. 2005. 135. 2082-2089).
Prospective study data - a meta-analysis of 29 prospective trials showed that eating at least 20 grams per day of nuts is associated with a lower risk of heart disease, stroke, and cancer (BMC Medicine. 2016. 14. 207).
In a prospective cohort study of 83,818 women from 11 states in the Nurses' Health Study, nut consumption and peanut butter consumption were inversely associated with the risk of developing type II diabetes (JAMA. 2002. 288. 2554-2560).
Nut consumption is inversely associated with the risk of gallbladder disease in the Health Professionals Follow-Up Study in men (437,305 person years of follow up) [Am J Epidemiol. 2004. 160. 961-968], and in Nurses’ Health Study in a cohort of 80,718 women (Am J Clin Nutr. 2004. 80. 76-81).
Nut consumption is inversely correlated with total mortality and inversely correlated with deaths due to cancer, heart disease, and respiratory disease, based on data in 76,464 women in the Nurses’ Health Study (1980-2010) and 42,498 men in the Health Professionals Follow-Up Study 1986-2010), representing 3,038,853 person years of follow up (N Engl J Med. 2013. 369. 2001-2011).
Telomere data
Leukocyte telomere length (number of base pairs) is considered a surrogate for biologic aging, with longer telomere length associated with slower biologic aging.
In a cross-sectional study of 5582 randomly selected men and women participating in NHANES 1999-2002, intake of nuts and seeds (by 24-hour dietary recall) was positively and linearly associated with telomere length (J Nutr Health Aging. 2017. 21. 233-240).
For much more information on nuts and their beneficial effects on lipid profiles, and also on cardiovascular events, go to the outline on this website, ‘Prevention of MI’ and scroll down to ‘nuts’ in the category of ‘Primary Prevention – Diet.’
Oils (Consumer Reports. October, 2022. 34-39)
Exposure of oils, especially polyunsaturated oils, to air or heat or light leads to oxidation of the oil, which produces a rancid oil, which is dangerous to ones health.
Minimize the risk of oxidation of the oil by purchasing all oils in darkened containers to protect from light.
Buy cooking oils in small quantities to protect the rest of the oil in the container from the air in the container once the container has been opened.
Refrigerate oils to protect from heat.
Heating oils beyond their smoking point causes chemical changes which are detrimental to a person’s health. Fast food restaurants do this all the time. Furthermore there is data that there are chemical changes in many oils well below their smoking point – this information should be available from Omega Nutrition, a reputable manufacturer of oils, 1-800-661-3529.
High-heat cooking: best to use coconut oil, peanut oil (organic preferred), or high oleic safflower oil.
Medium-heat cooking: may use olive oil, corn oil, or hazelnut oil.
Low-heat cooking: may use almond oil, sesame oil, sunflower oil, or butter.
Extraction of oil from the plant
The least damaging way to extract oil is to press the nut, seed or fruit until it oozes – this is called “cold-pressed” but it works only with soft raw materials.
BEWARE ‘cold-pressed’ is not defined from a regulatory standpoint in terms of maximum temperature at which the oil is expressed – it means that no added heat has been used, but there is no limit on the temperature achieved as a function of the pressure used to express the oil. These temperatures as a function of the high pressure alone may reach 200 degrees Fahrenheit. Expeller processed oils by voluntary standard should be manufactured at temperatures less than 118 degrees Fahrenheit.
Alternatives to cold-pressed are (1) expeller pressed or (2) chemically processed, in which the plant product is dissolved with toxic solvents and then the oil is refined, heated, and filtered. Oils extracted using chemicals usually will not say this on the label – look for the terms cold-pressed, expeller-pressed, and/or unrefined on the label to indicate that chemicals were not used.
Commercial oils are typically bleached, degummed, deodorized, and then stabilizers are added to the oil to increase shelf life. There is concern that these processes may cause undesirable chemical changes in the oil.
Organic oils are preferable, because many toxins are concentrated in the oil of plants.
Oils high in omega 6 fatty acids may have pro-inflammatory effects in the body, but this is controversial.
Choice of oils
Almond oil - mostly monounsaturated fats.
Canola oil – probably very good. It is obtained from rapeseed, and consists of mostly monounsaturated fat. Buy organic, expeller-pressed products as per Dr. Andrew Weil (Self Healing. 2/05. 3). The concern with canola oil is that rapeseed oil is toxic to animals and must be irradiated to create canola oil and the long term effects of this are unknown.
Coconut oil/butter – controversy regarding health benefits
Dr. Weil skeptical due to high saturated fat content
Health benefits are the focus of a book by Bruce Fife, The Coconut Oil Miracle (2004).
Heat stable to 375 degrees Fahrenheit.
Contains lauric acid, an antibacterial compound which may boost immunity..
Rich source of medium chain triglycerides, which are readily converted to energy
Corn oil – high in polyunsaturated fats and most often produced at high temperatures and using toxic solvents.
Cottonseed oil – not as high as other oils in polyunsaturated fats, but rich in saturated fat, and contains manufactured and natural toxins. Cotton is often sprayed with pesticides and herbicides banned for use on food crops, because it is not classified by the USDA as a food.
Enova – brand name of an oil touted to facilitate weight loss. Contains chemically altered fats.
Fish oil – this is considered a dietary supplement. For more information on therapeutic uses of fish oil, return to Home Page, click on “Dietary Supplements” and scroll to ‘Fatty acids’ then scroll on to ‘Fish oil capsules.’
Flax oil – this is a source of ALA, a short chain omega 3 fatty acid which is inefficiently converted into longer chain fatty acids
Grapeseed oil – advantage is high smoking point, potential disadvantage is polyunsaturated fat content.
Hazelnut oil – highly unsaturated, may be used as seasoning in cold dishes, but should never be heated.
Macadamia oil - mostly monounsaturated fats., and a very high smoking point, so good for cooking.
Olive oil - very good. It is mostly monounsaturated fat and also has antioxidant-rich polyphenols and flavonoids.
Olive oil consumption is associated with a lower risk of all-cause mortality and a lower risk of death due to cardiovascular disease, cancer, neurodegenerative disease, and respiratory disease, based on data generated from the Nurses’ Health Study (60,582 US women monitored from 1990-2018) and from the Health Professionals Follow-up Study (31,801 US men monitored from 1990-2018) The comparison was between those who consumed more than 0.5 tablespoons daily versus those who rarely consumed olive oil (J Am Coll Cardiol. 2022. 79. 101-112).
Heat stable to 300 degrees Fahrenheit (i.e. does not oxidize), but pan frying with olive oil significantly reduces the polyphenol content (Antioxidants. 2020. 9. E77).
Hydroxytyrosol, present predominantly in extra-virgin olive oil, appears to inhibit enzymes which involved in the production of pro-inflammatory eicosanoids. Hydroxytyrosol is also a potent antioxidant with a very high ORAC value. Olive oil rich in this compound can be purchased at www.Olio2go.com – it is expensive as per Barry Sears, Ph.D.
Oleocanthol, a phytochemical with COX-1 and COX-2 inhibiting properties, is found in extra-virgin olive oil, and appears to have anti-inflammatory activity similar to that of ibuprofen (Nature. 2005. 437. 45-46). This phytochemical causes a stinging sensation in the throat.
The polyphenols, which are most abundant in extra virgin olive oil, are cardioprotective – they inhibit platelet aggregation and LDL oxidation (Am J Clin Nutr. 2006. 84. 694-697).
Pomace oil is the lowest grade of olive oil available, manufactured by applying heat and/or solvents to the paste leftover after higher grades of oil have been extracted – it is thus inexpensive.
Palm oil
Palm fruit oil is 50% saturated fat, 40% monounsaturated fat, and 10% polyunsaturated fat, and has moderate antioxidant activity.
Palm kernel oil is >80% saturated fat, and often used in processed foods.
Peanut oil – 50% monounsaturated fats, 30% polyunsaturated fats.
Pistachio oil – mostly monounsaturated fats.
Safflower oil – highest in polyunsaturated fats. Safflower's history as a food plant in the Western world is very recent, and ancient medical texts in India recommend against consumption of this plant as food.
Sesame oil – high in polyunsaturated fats, but richly flavored, and contains small amounts of lignans, including sesamin, which is a direct inhibitor of the enzyme that facilitates production of arachadonic acid.
Soybean oil – also called ‘vegetable oil.’ High in polyunsaturated fats, but inexpensive. Due to difficulty in extracting oil from soybeans, soybean oil is often damaged in the process.
Sunflower oil – second highest in polyunsaturated fats.
Tea oil – advantage is high smoking point (over 400 degrees Fahrenheit) and composition, which is mostly monounsaturated fat, but it is expensive, and available only via www.republicoftea.com. Buy an organic, expeller-pressed product as per Dr. Andrew Weil (Self Healing. 6/04. 7).
Walnut oil - highly unsaturated, may be used as seasoning in cold dishes, but should never be heated.
Poultry
Beware of deceptive labeling (Consumer Reports. 2/14/ Pg 33)
Organic – loophole in labeling is that chickens treated with antibiotic while in egg stage are considered organic; organic means no antibiotic administered from first day of life until slaughter. A “no antibiotics” label means that antibiotics are not used, including in the egg.
‘Free range’ - defined by USDA as daily "access" to the outdoors. “The USDA considers opening the chicken coop door for 5 minutes each day adequate for the free-range distinction. The animal doesn’t even have to step outside” (Self Healing. 3/07. Pg 3. Pointer on Picking out Poultry).
“Cage free” – essentially meaningless term
‘No synthetic hormones used’ is meaningless because federal law prohibits use of synthetic growth hormones in poultry (and in pork).
MEANINGFUL TERMS: Certified Humane (inspections required to use this label), American Humane Certified (inspections required to use this label), Animal Welfare Approved (inspections required to use this label), pasture-raised (but this does not require inspections)
Measures to minimize risk of human bacterial infection from bacteria in/on the skin of poultry
Buy chicken last in the store, put in an additional plastic bag at the store to minimize cross contamination, place in refrigerator at home ASAP, wash hands after handling even the bag
Separate cutting board designated for raw meat
Do NOT wash chicken before cooking – this spreads bacteria
Wash hands after IMMEDIATELY after handling raw chicken
Use a meat thermometer, and cook to at least 165 degrees Fahrenheit.
Salt
Average salt intake in the U.S. in 2005-2006 was 10.4 grams per day for males (2 teaspoons) and 7.3 grams per day for females (USDA data posted on the USDA website).
NOTE 1 gram of salt = 0.4 grams sodium.
In the U.S. there has been a 55% increase in sodium intake from the 1970’s to 2000 (Prog Cardiovasc Dis. 2006. 49. 59-75).
77% of salt comes from processed and restaurant food, 12% occurs naturally in foods, 6% is added at the table, and 5% is added during cooking (J Am Coll Nutr. 1991. 10. 383-393).
A 2019 report from the National Academies of Sciences, Engineering and Medicine states that sodium intake should be reduced from an average of 3400 mg per day to 2300 mg per day.
Salt and health
A 2019 report from the National Academies of Sciences, Engineering and Medicine links excess sodium intake to cardiovascular disease, hypertension, and stroke.
The ratio of potassium: sodium may an important determinant of health - in Western diet, it is estimated at 3:1, whereas ratio in Paleolithic diet, it is estimated at 10:1 (Eur J Nutr. 2001. 40. 200-213).
Salt and blood pressure
A Cochrane analysis showed that reducing dietary salt intake lowers blood pressure (Cochrane Database Syst Rev. 2004. 3. CD004937), but only a subset of hypertensive individuals experience a decrease in BP with salt restriction.
A review of 167 studies, mostly small and short-term, found that low sodium intake was associated with reductions of systolic BP of 1-4 mm Hg in individuals in various ethnic groups without hypertension, and reductions of SBP of 6-10 mm Hg in individuals in various ethnic groups with hypertension (Am J Hypertens. 2012. 25. 1).
Data gathered on 102,216 adults in 18 countries (PURE study), in which sodium intake was estimated based on a calculation of 24 hour sodium excretion (24 hour excretion calculated based on measurement in a fasting morning urine sample) showed a correlation between sodium intake and diastolic and systolic BP, with the slope of the curve steeper at higher sodium intakes. In this same study, potassium excretion (a surrogate for potassium intake) was inversely related to BP, with a steeper slope for those with HTN and with increased age (N Engl J Med. 2014. 371. 601-611). See below for results of this study pertaining to sodium and potassium and cardiovascular disease
Salt and cardiovascular disease
NOTE the conclusion that reducing salt intake will reduce the risk of risk of CVD and CVA is based on the assumption that reductions in BP will reduce the risk of CVA and CHD (i.e. that BP is a surrogate marker). Some experts express concern that reduction in salt intake may unfavorably impact other cardiovascular disease surrogates, and thus reducing salt intake may not reduce risk of CVD and CVA (Commentary. JAMA. 2010. 303. 448-449).
Prospective data from NHANES III, with mean follow-up of 14.8 years in 12,267 US adults show that higher sodium intake was associated with increased all-cause mortality. In addition, higher sodium to potassium ratios of dietary intake were associated with increased all cause and CVD mortality (Arch Intern Med. 2011. 171. 1183-1191 and invited commentary 1191-1192). Additional prospective data from 8699 participants in NHANES III (J General Intern Med. 2008. 23. 1297-1302), 7154 participants in NHANES II (Am J Med. 2006. 119. E7-e14), and 20,729 participants in NHANES I (Lancet. 1998. 351. 8781-785) show an inverse correlation between sodium intake and cardiovascular mortality.
The authors of a systematic review and meta-analysis of 13 prospective studies representing data on 19 independent cohort samples with more than 175,000 subjects, conclude that cutting average salt intake by half might reduce the risk of stroke by 23% and heart disease by 17% (Strazzullo P et al. BMJ. 2009. 339. b4567). Salt intake was estimated in some studies by 24 hour dietary recall, in others by food-frequency questionnaire, and in others by measurement of 24 hour urine excretion; follow up ranged from 3.5 to 19 years. The higher the salt intake the higher the risk of CVD (RR 1.14) and CVA (1.23). The longer the period of follow up, the greater the risk of CVA.
A study exploring the potential impact of modest reduction in dietary salt on US population health, using a computer simulation of heart disease in US adults age 35-84 concludes that reducing dietary salt by 3 grams per day (dietary sodium by 1.2 grams per day) is projected to is projected to reduce the annual number of new cases of CHD by 60,000 to 120,000; the annual number of new cases of CVA by 32,000 to 66,000; the annual number of new cases of MI by 54,000 to 99,000, and the annual number of deaths from any cause by 44,000 to 92,000 (N Engl J Med. 2010. 362. 590-599). This intervention could save $10 - $24 billion annually in health care costs. The conclusion of the editorialist is that “The evidence supporting the call to reduce salt intake as a means of preventing cardiovascular disease is compelling.” (Editorial. N Engl J Med. 2010. 362. 650-652).
A cost effectiveness analysis using a Markov model concluded that “Strategies to reduce sodium intake on a population level in the United States are likely to substantially reduce stroke and MI incidence, which would save billions of dollars in medical expenses.” (Ann Intern Med. 2010. 152. 481-487 and editorial 526-527).
A meta-analysis identified only 7 RCTs of dietary sodium restriction in which cardiovascular disease incidence or mortality were used as endpoints; the results of the analysis showed no strong effect of sodium reduction on cardiovascular disease incidence or mortality (Am J Hypertens. 2011. 24. 843).
As of 2012, there are no large RCTs showing that sodium restriction lowers the risk of MI, stroke or death (The Medical Letter. 2012. 54. 13).
A Cochrane analysis of 7 RCTs (n=6489) showed that “Interventions to reduce dietary salt do not reduce mortality or cardiovascular morbidity in persons with normotension or hypertension” (Cochrane Database Syst Rev. 2011. CD009217 as cited in ACP Journal Club. 2012. 156. JC1-4). An updated Cochrane analysis in 2014 came to the same conclusions (Cochrane Database Syst Rev. 2014. CD009217).
A 2013 narrative review concludes “low sodium diets have not been shown to reduce cardiovascular events … Low sodium diets may adversely affect insulin resistance, serum lipids, and neurohormonal pathways, leading to increases in the incidence of new cardiometabolic disease, the severity of existing cardiometabolic disease, and greater cardiovascular and all-cause mortality” (Am J Med. 2013. 126. 951-955).
A meta-analysis of data from 23 cohort studies and 2 RCTs (n = 274,683) concludes that CVD events are lowest in those consuming 6728-9653 mg of salt daily (Am J Hypertens. 2014. 27. 1129-137).
Data gathered on 101,945 adults in 17 countries (PURE study), in which sodium intake was estimated based on a calculation of 24 hour sodium excretion (24 hour excretion calculated based on measurement in a fasting morning urine sample), “an estimated sodium intake between 3 g per day and 6 g per day was associated with a lower risk of death and cardiovascular events than was either a higher or lower estimated intake.” In this same study, a higher potassium excretion (a surrogate for potassium intake) was inversely related to risk of death and cardiovascular events (N Engl J Med. 2014. 371. 612-623). See above for results of this study pertaining to sodium and potassium and effect on BP.
However, in a modelling study reported in the same issue of NEJM, analysis of data on estimated sodium intake in persons in 66 countries concluded that “1.65 million deaths from cardiovascular causes that occurred in 2010 were attributed to sodium consumption above a reference level of 2.0 g per day” events (N Engl J Med. 2014. 371. 624-634). An accompanying editorial states “However, given the numerous assumptions necessitated by the lack of high-quality data, caution should be taken in interpreting the results of this study” events (N Engl J Med. 2014. 371. 677-679).
Possible harms of a low salt diet
Contrary to randomized, controlled clinical trial data showing a decrease in blood pressure in conjunction with reduction in salt intake, population data from NHANES I and NHANES III (Am J Hypertension. 2005. 18. 261) showed that low dietary intake of salt was associated with an increased risk for HTN.
In patients with CHF, those randomized to a sodium intake of 1840 mg/day had significantly increased hospitalization and mortality compared to those randomized to 2760 mg/day, based on data from an 8-arm, 6 month trial of 410 patients (Am J Cardiol. 2009. 103. 93-102).
In patients with type II diabetes, a low sodium diet is associated with cardiovascular and all-cause mortality, based on date from a cohort study in which 638 diabetic persons were followed for a period of 9.9 years (Diabetes Care. 2011. 34. 703-709).
In one study in ~3000 hypertensive men, low salt intake was associated with an increased risk of MI (Hypertension. 1995. 25. 1144-1152).
Reduction in salt intake sufficient to lower BP increases sympathetic nervous system activity, decreases insulin sensitivity, activates the rennin-angiotensin system, and stimulates aldosterone secretion (JAMA. 1998. 279. 1383-1391; J Hypertens. 2007. 25. 903-907).
Low salt intake is associated with hyperinsulinemia (J Intern Med. 1993. 233. 409-414).
Low salt diet increases serum cholesterol and LDL (Klin Wochenschr. 1991. 69 [suppl XXV]. 51-57).
Increases the half-life of bromine in the body, based on a study in rats (Chem Toxic. 1983. 21. 379).
Table salt is a processed “food” (Salt Your Way to Health by David Brownstein, MD. 2006)
Refined salt has all minerals (other than the sodium) removed and iodide added. The minerals are removed from the brine with chemicals such as chlorine or sulfuric acid. Next the water is evaporated under high pressure and heat. Dextrose is used as a stabilizer so that iodide will stay in salt. Refined salt is bleached so that it maintains the white color. Refined salt has a very long shelf life. More information on the refining process is available at www.saltinstitute.org.
The National Academy of Science Food Chemicals Codex Sodium Chloride Monograph (1996) permits food grade salt to contain anti-caking, free-flowing, and conditioning agents, such as sodium ferrocyanide, ammonium citrate, and aluminum silicate as long as the additives constitute no more than 2% of the contents of the final food grade salt product.
Refined salt consists of approximately 39% sodium, approximately 60% chloride, up to 2% additives (see just above), 0.01% iodide.
Unrefined salt contains more than 80 minerals and elements in minute amounts, along with the sodium and chloride.
Celtic Sea Salt contains 33% sodium, 50.9% chloride, 1.8% minerals and trace elements, and 14.3% moisture. More information on Celtic Sea Salt is available through The Grain & Salt Society (800-867-7258).
Redmond’s Real Salt contains 37.6% sodium, 59.1% chloride, approximately 1% minerals and trace elements.
Soda
Diet soda – see ‘artificial sweeteners’ below in this outline. In addition to the detrimental effects of the artificial sweeteners, the caffeine prompts conversion of ATP to AMP, and detection of this ‘spent fuel’ may increase appetite and thirst.
In a meta-analysis of 88 studies, the authors found clear associations of soft drink intake with increased energy intake and body weight, and with an increased risk of several medical problems such as diabetes. The studies using the most reliable statistical methods showed the largest effects. Several studies found that the caloric increase is actually greater than that contained in the soda, raising “the possibility that soft drinks increase hunger, decrease satiety or simply calibrate people to a high level of sweetness that generalizes to preferences in other foods… These results, taken together, provide clear and consistent evidence that people do not compensate for the added calories they consume in soft drinks by reducing their intake of other foods” (Am J Public Health. 2007. 97. 667-675).
In a study of 91,249 women followed for eight years, those who consumed one or more soft drinks per day were twice as likely as those who consumed less than one per month to develop diabetes.
Consumption is associated with an increased risk of gout in men, with the risk 85% higher in men who consumed two or more servings daily, compared with men consuming no soda (BMJ. 2008. 336. 309-312).
High fructose corn syrup is soda – for details on potential harmful health effects scroll up to the section of this outline on ‘Functional Classification of Carbohydrates’ (approximately page 16 of this outline).
Consumption of one soda daily is associated with a 20% increased risk of coronary heart disease (Circulation. 2012; DOI: 10.1161/CIRCULATIONAHA.111.067017).
“The genetic association with adiposity appeared to be more pronounced with greater intake of sugar-sweetened beverages,” based on cohort data in 6934 women in the Nurses’ Health Study and 4423 men in the Health Professionals Follow-up Study (N Engl J Med. 2012. 367. 1387-1406 and editorial 1462-1463).
In an 18 month trial in 641 primarily normal weight children, “Masked replacement of sugar-containing beverages with noncaloric beverages reduced weight gain and fat accumulation …” (N Engl J Med. 2012. 367. 1397-1396 editorial 1462-1463).
A review reports that daily consumption of sugar-sweetened beverages is associated with a 26% higher risk of developing type II diabetes, a 35% higher risk of a heart attack, and a 16% increased risk of stroke (J Am Coll Cardiol. 2015. 66. 1615-1624).
Consumption of at least two daily 200-ml serving of a sweetened beverage (including soda, sugar-sweetened beverages and artificially sweetened beverages) is associated with a 2-fold increased risk of latent autoimmune diabetes of adults (LADA) and a 2.4-fold increased risk of type 2 diabetes, based on data from a Swedish population-based case control study, ESTRID (Eur J Endocrinol. 2016. 175. 605-614).
Sodium benzoate, a common preservative found in many soft drinks, might damage mitochondrial DNA, based on laboratory data in living yeast cells (accessed 6/19/07 at www.mercola.com). Sodium benzoate, which occurs naturally in berries in small amounts, is used in large quantities to prevent mold in soft drinks such as Sprite, Diet Pepsi, Coca-Cola, and Dr Pepper.
BEWARE that soda with added vitamin C and with sodium benzoate as a preservative may have benzene levels above the EPA limit of 5 ppb for drinking water. In a recent FDA and EPA study, almost 5% of 200 beverage samples had benzene levels above 5 ppb (accessed 1/26/08 at www.mercola.com).
Soy
EXCELLENT REVIEW ARTICLE (120 references): D’Adamo CR and Sahin A. Altern Ther Health Med. 2014. 20[suppl 1]. 39-51.
OTHER REVIEWS: Alternative Medicine Alert. 2004. 7. 49-55; Consumer Reports. 7/04. 28-31.
Popularity:
In 2005, Americans were estimated to spend $4.7 billion on soy foods, an 844% increase over 1990.
Sales of soy supplement pills rose more than 500% between 1997 and 2002 according to the Nutrition Business Journal.
Nutrient composition:
Soy protein contains the 8 essential amino acids also present in animal protein. Soy protein has the highest nutritive value of any plant source; the overall quality of the protein is similar to that of meat, milk and eggs. HOWEVER, soy has suboptimal amounts of sulfur-containing amino acids (cysteine and methionine) and modern processing of soy denatures some of the lysine.
Soy is rich in essential fatty acids, but contains much less saturated fat than animal protein, and no cholesterol.
Soy is rich in minerals, but also rich in “antinutrients (oxalates, saponins, lectins, phytates, and others) which may interfere with absorption of vitamins and minerals. Fermentation, germination, soaking for at least 12 hours, and cooking all may reduce the concentration of antinutrients.
Soy contains vitamin E, oligosaccharides, lecithin, and saponins, all of which are bioactive compounds.
Soy contains isoflavones (soy foods on average contain 3.5mg isoflavones/gram of protein)
The main isoflavones in soy are genistein, daidzein, and glycitein.
Isoflavones are believed to act as weak estrogens, reversibly binding to estrogen receptors, with a greater affinity for the beta isoform (found mostly in the nervous system, cardiovascular system, bone, and skin) than the alpha isoform (found mostly in the uterus and breast).
There are two types of isoflavones in soy - aglycones and glucosides.
Aglycones are the active ingredient, and are found in fermented soy foods, as a result of enzymatic hydrolysis during fermentation.
Glucosides are aglycones with a glucose molecule attached – the isoflavones in non-fermented soy foods exist in this form. These are converted by intestinal bacteria into the biologically active aglycone form, but the conversion rate is only approximately 60%. Human GI juices do not contain glycosidases.
Daidzein is converted in the gut into a bioactive metabolite named equol which is a more potent, possessing estrogenic activity approximately five times greater than its precursor. The extent of this conversion is dependent in part upon the amount of prebiotic in the diet and in part upon the composition of the GI flora – some lactobacilli such as Lactobacillus sporogenes facilitate this conversion.
Note that ipriflavone is a synthetic isoflavone, derived from soy isoflavones.
Categories of soy products:
Fermented soy foods - historical use of soy by the Japanese is use of predominantly fermented products such as tempeh, miso (soup), and natto (a fermented cheese). Fermentation reduces the levels of isoflavones 2-3 fold.
Whole soy foods – there is some historical use of these non-fermented whole foods such as tofu, soy nuts, soy milk and edamame (lightly broiled soybean pods).
Note though that American strains of soya plants have significantly higher levels of isoflavones than Japanese or Chinese ones because of selective breeding in the U.S. to promote pest resistance of the plants.
Note hexane is typically used in the processing of soy milk and tofu; health effects are unknown. Hexane is a neurotoxin.
Edamame is young green beans which are lower in estrogens and antinutrients than the mature plant.
Processed soy – soy protein concentrate, soy protein isolates, texturized soy protein. Processing with alkaline solutions creates the unnatural amino acid lysinoalanine and also creates D-isomers of naturally occurring L-amino acids - may have unfavorable health effects.
These are not whole foods and there is no significant historical use, so safety is unknown.
Made by isolating the soy protein from the carbohydrate and fat.
Often found in cereals, energy bars, patties, crackers, spaghetti sauce, and as an inexpensive filler to lower a food’s overall fat content.
Supplements
Controversy about relative benefit versus risk of soy
10,000 soy-related articles published between 1990 and 2005, and the literature is conflicting, so anyone can selectively use the published literature to argue any point about safety or risk.
Likely that fermented soy foods in moderation are safest, whole soy foods in moderation are safe too, with long-term safety of processed soy products and supplements an unknown.
Regarding the therapeutic health claim for soy and cholesterol-lowering (See Health Benefits just below) the concern of some is that the long-term safety of these quantities of soy, even if consumed in whole foods form, is unknown because it exceeds historical use of 10 grams of soy protein per day. Two FDA scientists formally protested the decision to grant a therapeutic label claim due to lack of data on long-term safety of this magnitude of daily consumption.
An evidence-based report, “Effects of Soy on Health and Outcomes” was requested and funded by NCCAM and NIH Office of Dietary Supplements, and published in 2005. It concluded that eating soy protein daily may have some health benefits, but overall the health effects of soy are uncertain and need further investigation. Summary of report available at www.ahrq.gov/clinic/epcsums/soysum.htm or 1-800-358-9295.
Health benefits:
Atherosclerosis prevention – soy may be beneficial based on data that genistein inhibits thrombin formation and platelet aggregation, and inhibits cell adhesion and proliferation.
Benign prostate hypertrophy (BPH) – the beta-sitosterol in soy is beneficial (Lancet. 1995. 345. 1529-1532).
Blood pressure lowering
A RCT in 40 men and women showed that soy milk 500 ml bid, as compared with cow’s milk 500 ml bid, was associated with a 17/12 mm Hg decrease in BP (J Nutr. 2002. 132. 1900-1902).
A longitudinal study of soy food intake and blood pressure in 45,000 Chinese women aged 40-70 showed that women who consumed more than 25 grams of soy per day had on average a 1.9 mm Hg lower systolic BP and a 0.8 mm Hg lower diastolic blood pressure (Am J Clin Nutr. 2005. 81. 1012-1017).
An 8 week crossover RCT in 60 healthy postmenopausal women found that substituting soy nuts (25 gm of soy protein per day) lowered SBP 9.9% and DBP 6.6% in hypertensive (SBP > 140) women; lowered SBP 5.2% and DBP 2.9% in normotensive (SBP < 120) women (Arch Intern Med. 2007. 167. 1060-1067).
Cancer prevention - data is mixed. Epidemiological studies show a decreased risk of breast, colon, lung, and prostate cancer. The epidemiological data on lung cancer comes from a case control study in 1674 patients and 1735 matched controls (JAMA. 2005. 294. 1505-1510). Soy isoflavones shift estrogen metabolism toward more beneficial metabolites (i.e. 2 hydroxyestrone). Isoflavones interfere with angiogenesis in vitro (Nutr Cancer. 1994b. 21. 113-131). Soy increases synthesis of SHBG and inhibits aromatase.
Cholesterol lowering - based on a meta-analysis of 38 controlled clinical trials showing a 9% decrease in total cholesterol and a 13% decrease in LDL cholesterol in patients taking 25-50 grams per day of soy (New Engl J Med. 1995. 333. 276-282), the FDA as of 1999 actually allows a therapeutic label on soy rich foods (6.25 grams of soy per serving) - "capable of decreasing the risk of heart disease." Presumed mechanism of action – reduced hepatic cholesterol synthesis. It has been proposed that only the 1/3 of individuals who convert daidzeinto equol benefit from soy with regard to the lipid profile. The ability to convert daidzein to equol appears to be related to specific gut flora.
Cognitive function preservation - data is promising.
Coronary heart disease prevention - Effective October 1999, the FDA allows for labeling on soy rich foods (defined as having at least 6.25 grams of soy per serving, and assuming 4 servings per day) as "capable of decreasing the risk of heart disease" (Fed Regist. 1999. 64. 57700-57733) based on a meta-analysis of 38 clinical trials showing a 9% decrease in total cholesterol and a 13% decrease in LDL cholesterol in patients taking 25-50 grams of soy per day (N Engl J Med. 1995. 333. 276-282).
Heart rate variability – increased with consumption of soy (Chest. 2005. 127. 1102-1107).
Hot flashes - clinical trials is mixed; a meta-analysis of 17 RCTs of soy isoflavones found a pooled reduction of 20.6% in frequency and 26.2% in duration of hot flashes (p<0.0001) [Menopause. 2012. 19. 776-790].
Osteoporosis prevention - animal data very promising, but human data mixed. A literature review suggests that soy supplementation does not offer protection against osteoporosis (Altern Ther Health Med. 2014. 20[suppl 1]. 39-51).
Vaginal atrophy prevention - data is mixed.
Potential health risks:
Soy foods are presumed safe because they have been consumed in Asia for thousands of years - consumption of up to 100 mg of aglycone isoflavones per day (10 grams of soy protein) in food is presumed safe.
Alkaline processing to create textured soy protein and hexane processing in the production of soy milk and tofu – health effects unknown
Allergy - it is estimated that 5 to 7% of babies and 1 to 2% of adults are allergic to soy.
Antinutrients (oxalates, saponins, lectins, phytates, and others) - may interfere with absorption of vitamins and minerals. Fermentation, germination, soaking for at least 12 hours, and cooking all may reduce the concentration of antinutrients.
Breast cancer – there are concerns that soy might stimulate breast cancer cells, or alter the effectiveness of hormonal therapy for breast cancer. However, most epidemiologic data shows an inverse correlation between soy consumption and breast cancer, and several studies of soy intake in those with breast cancer also show a protective effect
Endometrial hyperplasia - soy isoflavones 150mg/day for 5 years caused endometrial hyperplasia in 3.9% of women, although no endometrial hyperplasia seen after 2.5 years (FertilSteril. 2004. 82. 145-148).
Kidney stones - soy may increase the risk of calcium oxalate kidney stones.
Lipoprotein (a) - soy may increase lipoprotein (a) levels.
Reproductive hormone levels
Soy consumption may affect reproductive hormone levels in men – theoretical concern, but a meta-analysis shows no significant effect on total testosterone, free testosterone, SHBG, or free androgen index. (Fertil Steril. 2010. 94. 997-1007).
Soy consumption may affect an infant's hormone levels – theoretical concern
Thyroid function
Inconsistent findings in published studies – the authors of a review article (Altern Ther Health Med. 2014. 20[suppl 1]. 39-51) conclude “these inconsistent findings are suggestive that soy supplementation can indeed interfere with thyroid function in an unpredictable manner.” The authors state further in the final “Discussion” section of the article “This review revealed evidence from randomized, controlled trials that soy supplementation can both increase and decrease thyroid activity among people with normal thyroid function. These variable effects provide cause for concern, and more studies are needed.”
Soy consumption may increase the risk of hypothyroidism in the presence of an iodine deficiency; the effect may be offset by iodine supplementation.
A RCT in 38 postmenopausal women not on hormone replacement therapy and taking a product with 90 mg/day of isoflavones found no changes in serological assessment of thyroid function (J Med Food. 2003. 6. 309-316).
Thyroid medications - soy may interfere with absorption.
Vascular endothelial function - soy intake in men has been associated with a decline in vascular endothelial function.
Labels on food and supplements:
Consumer Reports found that eleven of the foods analyzed overstated their level of isoflavones.
A food's label often does not distinguish the amount of aglycone isoflavones versus glucoside isoflavones.
When soy protein is used as an inexpensive filler to lower a food’s fat content, it may appear under deceptive label terms such as ‘natural flavors’ or ‘vegetable protein.’
Sugar – see section on ‘Sugar’ in the category ‘Carbohydrates’ at the top of this outline.
Sugar-sweetened beverages (SSB) - data on health risks is mixed
NOTE approximately 65% of adults in the US consume sugar sweetened beverages daily.
A meta-analysis of of prospective studies (n = 173,753) found a 16% increased relative risk of CHD for each additional serving of sugar-sweetened beverages (Atherosclerosis. 2014. 234. 11-16).
In a prospective study of the Framingham Heart Offspring Study cohort, intake of sugar-sweetened beverages was not associated with an increased risk of cerebrovascular disease (Stroke. 2017. 48. 1139-1146).
Data from the Health Professional Follow-up Study shows that those in the highest quartile of consumption of sugar-sweetened beverages had a 24% increase relative risk of developing type 2 diabetes (Am J Clin Nutr. 2011. 93. 1321-1327).
Intake is associated with obesity and dental caries.
A systematic review of 12 studies (n = 409,707; 6 studies cross sectional; 6 studies prospective found that all 12 studies showed a correlation between increased intake of sugar-sweetened beverages and hypertension, with 10 of the 12 studies showing a statistically significant correlation. Of the 12 studies, 5 reported an increase in mean blood pressure; 7 reported an increase in the incidence of hypertension.
In a prospective cohort study which included 37,716 men from the Health Professionals Follow-up Study (from 1986 - 2014) and 80,647 women from the Nurses’ Health Study (from 1980 - 2014) who were free of chronic disease at baseline, during 3,415,564 person years of follow up, and after adjusting for confounding variables, when the highest (> 2 servings SSB/day) and lowest (< 1 serving SSB/month) categories of intake of sugar-sweetened beverages were compared, highest intake was associated with a 21% increased risk for total mortality (95% CI 1.13 - 1.28, p < 0.001), 31% increased risk for cardiovascular mortality, and 16% increased risk for cancer mortality. The association was stronger in the Nurses’ Health Study than in the Health Professionals Follow-up Study. The magnitude of effect of artificially sweetened beverages in these studies was much less than the magnitude of effect of SSB (Circulation. 2019. 139. 2113-2125).
Epidemiologic studies (a systematic review and dose-response meta-analysis of observational studies) report positive associations between intake and risk of breast, colorectal, and prostate cancers (J Cancer. 2021. 12. 3077-3088).
In a prospective cohort of 98,786 postmenopausal women enrolled in the Women’s Health Initiative (WHI), those who consumed one or more sugar-sweetened beverages daily had a higher incidence of liver cancer and death from chronic liver disease, as compared with those who consumed 3 or fewer servings per month (JAMA. 2023. 330. 537-546).
Sweeteners
Natural sweeteners
GENERAL STATEMENTS
Some such as honey and maples syrup “are just sugar in liquid form” and while they can definitely add flavor to food, and are OK to use in small quantities, some such as honey and maples syrup have more calories per unit weight than does (processed) table sugar.
While natural sweeteners do have nutrients, in the quantities that natural sweeteners are consumed, nutrient and antioxidant intake is minimal.
Research on the health effects of natural sweeteners is very limited, as of 2024; in the absence of research, it is important to recall that natural does NOT always equate with safety (Consumer Reports. October 2024. Pages 22-27).
Allulose (also known as D-psicose)
Naturally occurring sugar found in small quantities in jackfruit, figs, and raisins.
Taste and texture similar to sucrose, but 90% fewer categories.
Received GRAS status from FDA in 2011.
Limited clinical trial data in 2016.
Agave nectar – glycemic index lower than other natural sweeteners, secondary to high ratio of fructose to glucose, BUT beware that excessive fructose intake correlates with liver issues
Barley malt – mostly maltose, which does not directly activate an insulin response
Birch sugar and/or Birch syrup
Brown rice sugar – mild sweetener which is a healthier alternative than brown sugar.
Csweet – brand name for a product in which the natural ingredient is brazzein, a sweet protein from the berries of a West African plant named Pentadiplandra Brazzeana, and said to be 1,000 times sweeter than sugar with no undesirable aftertaste.
Date sugar
Erythritol (Sweet Simplicity) – sugar alcohol
Fructooligosaccharides (FOS) – this natural product also serves as nutrition for friendly bacteria in the gut.
Honey – made from flower nectar of honeybee, contains vitamins and minerals and antioxidants.
Inulin – sweet probiotic.
Just Like Sugar – ingredients include chicory root dietary fiber, calcium, vitamin C, and natural flavors from the peel of the orange. www.justlikesugarinc.com
Lohan fruit (Sweet Balance) – 250 times as sweet as sugar, contains a small amount of sugar, and may contain antioxidants.
Maltitol (Nature Sweet) – sugar alcohol
Maple sugar and/or Maple syrup
Miracle berry
Molasses (blackstrap) – originally from Caribbean islands, rich in minerals.
Monk fruit (BioVittoria) – grown in Southern China, 300 times as sweet as sugar
Rapadura – brand name product derived from juice of sugarcane plant.
Sorbitol - sugar alcohol
Stevia (PureVia, SweetLeaf Stevia, Truvia) – 250-300 times as sweet as sugar
Used for centuries in South America (in small quantities). There is a slightly bitter aftertaste.
Used in Japan as a sweetener, but not approved as a sweetener in the U.S., in Canada, or by the European Union.
Available in the U.S. as a ‘dietary supplement.’
In 1998, a United Nations expert panel identified unresolved concerns about its toxicity.
Animal studies identify reproductive problems, cancer, and interference with energy metabolism as areas of potential concern, especially if large quantities are consumed.
Nonprofit Center for Science in the Public Interest recommends avoiding it.
Sucanat
Tagatose – made from milk sugar, approximately as sweet as sugar with 1/3 the calories and appears safe.
Vegetable glycerin
Xylitol – first manufactured in 1891, became popular in Finland after World War II.
Natural substance (a 5 carbon sugar alcohol) found in fibrous vegetables and fruit, and in various hardwood trees.
Humans synthesize up to 15 grams per day during normal metabolism.
Has 1/3 the calories of sucrose (table sugar), and is approximately 2/3 as sweet as table sugar.
Non-fermentable and cannot be converted to acid by oral bacteria, and thus inhibits plaque formation.
The dose required to prevent cavities is 6 grams/day
Glycemic index is 7 when a scale designating sucrose as 100 is used.
Zsweet – erythritol (a sugar alcohol found in many fruits) – approximately 70% as sweet as sugar. Considered safe by the FDA
Artificial sweeteners
BEWARE artificial sweeteners can be “hidden” in many foods such as oatmeal, bread and English muffins (Consumer Reports on Health. February 2023; Consumer Reports. October 2024. Pages 22-27).
In order to determine whether there are sweeteners and a food, one must read the fine print/list of ingredients, and be familiar with the various names of the dozens of artificial or natural sweeteners.
Beware of deceptive labeling, as foods labeled "lower sugar" or "no sugar added" may contain artificial or natural sweeteners.
A practical way to reduce intake of sweeteners is to cut down on intake of packaged and processed foods
Artificial sweeteners stimulate appetite through the cephalic phase response - the brain associates sweet taste with introduction of new energy (i.e. food) into the body. thinks real sugar is in the system.
Production of insulin is triggered – insulin then halts the production of sugar from protein and starch reserves, and facilitates storage in the cells of metabolic fuel circulating in the blood.
Since no new energy (i.e. glucose) has actually been introduced into the body, relative hypoglycemia develops, and this triggers hunger, which prompts intake of food.
Other than aspartame, which is very low calorie (200 times sweeter than sugar) the artificial sweeteners are non-nutritive sweeteners, as they provide no calories and no nutrients
Artificial sweeteners (diet soda) and effect on body weight
A meta-analysis of 15 clinical studies concludes that non-nutritive sweetener consumption is associated with weight loss, reduced fat mass, and decreased waist circumference (Miller PE et al. Am J Clin Nutr. 2014).
However, in the SALSA study, a prospective cohort study of 749 individuals over age 65 followed for 10 years, there was a positive dose-response relationship between diet soda intake and waist circumference (Am J Geriatr Soc. 2015. 63. 708-715).
Artificial sweeteners and the immune system
In a study in mice, sucralose interfered with immune system function, and increased susceptibility to infection (Nature. 2023. 615. 705-711).
Sucralose consumption was associated with increased tumor growth in mouse models of lymphoma and pancreatic cancer (Nature. 2023. 615. 705-711).
Artificial sweeteners and autism - a study in which retrospective questionnaires were completed by mothers of 235 young boys diagnosed with autism spectrum disorders, and 121 young boys who were deemed "neurotypical" for their age showed a correlation between maternal consumption of aspartame containing products and autism - the retrospective data showed that young boys diagnosed with autism or 3 times as likely to have been exposed to aspartame in utero or in early life (breast-feeding), compared with controls (Fowler S, et al. Nutrients. September 2023).
Artificial sweeteners and cancer
Consumption (especially aspartame and acesulfame potassium) is associated with increased cancer risk, based on data from a prospective cohort study of 103,388 participants, the web based NutriNet-Santé cohort (mean age 42.2±14.4, 79.8% female, 904 206 person years). Dietary intakes and consumption of artificial sweeteners were assessed in this study by repeated 24 hour dietary records, including brand names of industrial products (BMJ. 2022; 378:e071204).
In 2023, the World Health Organization’s International Agency for Cancer Research deemed aspartame “possibly carcinogenic to humans.” The FDA dismissed the data as indeterminate.
Artificial sweeteners and cardiovascular disease.
Consumption (especially aspartame, acesulfame potassium, and sucralose) is associated with increased cardiovascular disease risk, based on data from a prospective cohort study of 103,388 participants, the web based NutriNet-Santé cohort (mean age 42.2±14.4, 79.8% female, 904 206 person years). Dietary intakes and consumption of artificial sweeteners were assessed in this study by repeated 24 hour dietary records, including brand names of industrial products (BMJ. 2022; 378:e071204).
A prior publication also suggested an increased risk of cardiovascular disease (Vyas et al. J Am Coll Cardiol. 2014).
Erythritol is associated with increased cardiovascular risk in 3 independent cohorts. Furthermore, experimental data shows that erythritol enhances platelet activation in vitro, as well as thrombosis formation in the human blood sugar (Nat Med. 2023. 29. 710-718).
Artificial sweeteners and depression - a 2023 study in JAMA Network Open of more than 30,000 women reported that those with the highest intake of artificial sweeteners at the greatest risk of depression (cited by Consumer Reports. October 2024. Pages 22-27).
Artificial sweeteners and diabetes
In a large European cohort, consumption of drinks was associated with an increased risk of diabetes (Fagherazzi et al. AJCN. 2013).
There is data that artificial sweetener consumption is associated with glucose intolerance, and this may be mediated by effects of artificial sweeteners on the microbiome (Suez J et al. Nature. 2014).
Artificial sweeteners disturb the gut microbiome, and this is the presumed mechanism by which artificial sweeteners are associated with glucose intolerance and weight gain (Nature. 2014. 514. 181-186).
Acesulfame potassium (Sunett, Sweet One) – 200 times sweeter than sugar, safety questionable based on animal studies.
Advantame - 20,000 times sweeter than sugar
Aspartame (NutraSweet, Equal) -200 times sweeter than sugar
History: Compound discovered in 1965, and entered the US market in 1974.
Metabolized to aspartate acid (an excitatory neurotransmitter), phenylalanine and methanol (and methanol further metabolized to formaldehyde).
Aspartame and insulin secretion - a study in 15 healthy, normal weight adults showed that aspartame was still detectable in the saliva 120 minutes after consumption, and this triggered increases in salivary insulin. Aspartame had a greater magnitude of effect on salivary insulin than did sugar-sweetened drinks, based on area under the curve (Finassi CM, et al. Food Res International. 2023).
More information in the movie Sweet Misery: A Poisoned World by Cory Brackett (which can be ordered at www.soundandfury.tv) and the books Excitotoxins: The Taste that Kills by Russell L. Blaylock, MD and Sweet Deception by Joseph Mercola, DC.
As per Mark Hyman, MD, of 166 studies on the safety of aspartame, 100% of the 74 studies funded at least in part by industry found aspartame safe, while 92% of the 92 independently funded studies identified potential safety and adverse effect issues (Ultrametabolism. 2006. Pg 99).
A review concluded that “Aspartame disturbs amino acid metabolism, protein structure and metabolism, integrity of nucleic acids, neuronal function, endocrine balances and changes in the brain concentrations of catecholamines. It was also reported that aspartame and its breakdown products cause nerves to fire excessively, which indirectly causes a very high rate of neuron depolarization. The energy systems for certain required enzyme reactions become compromised, thus indirectly leading to the inability of enzymes to function optimally. The ATP stores in the cells are depleted, indicating that low concentrations of glucose are present in the cells, and this in turn will indirectly decrease the synthesis of acetylcholine, glutamate and GABA (gamma-aminobutyric acid). The intracellular calcium uptake is altered, thus the functioning of glutamate as an excitatory neurotransmitter is inhibited. Furthermore, mitochondria are damaged, which could lead to apoptosis of cells and also a lowered rate of oxidative metabolism, which in turn could lead to lower concentrations of the transmitters glutamate and production of GABA. The cellular walls are destroyed with the result that the endothelial cells of the capillaries are more permeable, leading to a compromised blood brain barrier. Thus, overall oxidative stress and neurodegeneration are present” (Eur J Clin Nutr. 2008. 62. 451-462).
Despite review articles which have concluded that aspartame does not increase cancer risk (Regul Toxicol Pharmacol. 2002. 35. S1-93; Ann Oncol. 2004. 15. 1460-1465), there is evidence of carcinogenicity in a study in Sprague-Dawley rats, animals which are deemed a consistent predictor of human cancer risk (Environ Health Perspect. 2006. 114. 379-385).
Long term intake may deplete the body of glutathione, an important antioxidant (Food Chem Toxicol. 2011. 49. 1203-1207).
May lead to increased food/calorie intake (Physiol Behav. 1990. 47. 555-559; Int J Obes Relat Metab Disord. 1997. 21. 37-42).
There are published case reports of grand mal seizures, urticaria, angioedema, mania, panic attacks, migraines, and headaches associated with aspartame ingestion.
The methyl esters in aspartame are also of concern, in terms of both neurological and endocrine toxicity.
Individuals who are heterozygous for PKU ( approximately 4 million Americans) may be especially sensitive to the effects of aspartame.
There is concern that one of the metabolites, aspartate, an excitatory neurotransmitter may increase the risk of a variety of conditions, including ADHD, ALS, Alzheimer's disease, brain tumors, headaches, Parkinson’s disease, and seizures.
Same energy content as sucrose (4 kcal/g), but 160-220 times sweeter than sugar.
Erythritol - in petri dish, increases platelet aggregation
Neotame
Saccharin (Necta Sweet, Sweet ‘N Low) – 300-700 times sweeter than sugar; linked with cancer in animals in high doses, but probably safe in humans.
Sucralose (Splenda)
This is a sugar alcohol created via chemical substitution of 3 hydroxyl groups with 3 chloride atoms, creating a chlorocarbon (similar in chemical structure to DDT).
There is concern amongst some experts that this chemical structure may adversely affect normal metabolism.
An animal study found that sucralose (1) alters gut microflora, reducing good gut bacteria, increases intestinal p-glycoprotein, and (3) alters the function of the cytochrome P450 enzyme system (and thus reduces bioavailability of some orally administered medications (J Toxicol Environ Health. 2008. 71. 1415-1429).
May cause GI side effects in some individuals.
May trigger migraines in some individuals (Headache. 2006. 46. 1303-1304).
Introduced in 2000; 600 times sweeter than sugar.
Tagatose (Naturlose)- derived from sugar
Tea
Derived from the plant Camellia sinensis.
Five types of tea (note herbal teas are technically not tea; they are tisanes)
Black tea is fermented (oxidized). The leaves are rolled or crushed to release an enzyme that oxidizes its catechins. An 8 ounce cup contains 30-50 mg of caffeine (compared with 100 mg of caffeine in an 8 ounce cup of coffee). Blends of black tea include Darjeeling, Earl Grey, and English breakfast.
Green tea is unfermented. The leaves are steamed to prevent oxidation. An 8 ounce cup contains approximately 30 mg of caffeine.
Oolong tea is partially fermented. The leaves are partially dried and then rolled to allow for partial oxidation. An 8 ounce cup contains approximately 30-50 mg of caffeine.
Pu Erh tea (a Chinese tea) is prepared by fermenting damp tea leaves for up to 30 years. An 8 ounce cup contains 30-100 mg of caffeine
White tea is unfermented. It is prepared from young tea leaf buds which are rapidly steamed and dried to prevent oxidation. An 8 ounce cup contains approximately 35 mg of caffeine.
Of the approximately 2.5 million metric tons of dried tea manufactured, only 20% is green tea and less than 2% is oolong tea.
Historically, green tea has been consumed primarily in Japan, China, and a few countries in North Africa and the Middle East.
Tea contains over 400 volatile compounds, including polyphenols, which are potent antioxidants.
The four major polyphenols in green tea are EC, EGC, ECG, and EGCG. The usual concentration of total polyphenols in dried green tea leaves 8-12%.
Tea contains approximately 35-50 mg caffeine per 8 ounce serving. The L-theanine in tea may moderate the effects of the caffeine.
From a scientific nomenclature standpoint, herbal ‘teas’ are actually herbal infusions, and tea refers only to the beverage derived from the plant Camellia sinensis.
Practical tips (Self Healing. 12/08)
Beware that adding ice may cause the polyphenols and caffeine to bind together and sink to the bottom of the cup, where they are less likely to be consumed.
Beware that adding milk to tea may interfere with the absorption of the beneficial polyphenols.
Decaffeinated tea - look for varieties that use carbon dioxide and water rather than a solvent such as ethyl acetate, as use of solvents is associated with a lower catechin content.
Benefits of green tea
Preliminary data suggests benefits of green tea include antiviral, antifungal, and antioxidant effects; protection against cancer (stimulates apoptosis, antiangiogenic effect), heart disease, and neurological disease; treatment of diabetes, HIV, and inflammatory bowel disease; and increased thermogenesis (Pastore R and Fratellone P. Potential Health Benefits of Green Tea: A Narrative Review. Explore. 2006. 2. 531-539. 68 references; Mayo Clin Proc. 2007. 82. 725-732. 82 references).
Polyphenols found in tea inhibit the growth of pathogenic intestinal bacteria while leaving beneficial bacteria unharmed (Res Microbiol. 2006. 157. 876-84).
Green tea consumption has a beneficial effect on endothelial function, improving flow-mediated dilation of the brachial artery in a study in 14 healthy individuals (Eur J CardiovascPrev Rehabil. 2008. 15. 300-305). EGCG “can augment nitric oxide status and reduce endothelin-1 concentrations and thereby may impove endothelial function” (Am J Clin Nutr. 2008. 88. 1018-1025).
Green tea extract reduces BP, LDL cholesterol, and inflammation (Nantz MP et al. Nutrition. Epub 10/8/08).
Green tea consumption is associated with a decreased risk of osteoporosis (Nutrients. 12/26/21).
Green tea consumption is associated with a decrease in all-cause mortality, based on prospective data from 90,914 Japanese individuals followed for a mean of 18.7 years. (Ann Epidemiol. 2015. 25. 512-518).
Mechanism of action - caffeine is a molecule which binds to the same receptor as adenosine, and thus caffeine blocks adenosine from binding to its receptor. Adenosine levels gradually increase during the day, each day, and adenosine is a psychoactive compound that has hypnotic effects on the brain when it binds to its receptor.
Safety of green tea
May interfere with warfarin, based on case reports (Ann Pharmacother. 1999. 33. 426-428).
No significant effects on blood counts or blood chemistry profiles of healthy individuals after repeated administration of 800 mg of EGCG daily (Clin Cancer Res. 2003. 9. 3312-3319).
The tea plant absorbs fluoride (and aluminum), with the amount depending in part on the acidity of the soil (Toxicol Lett. 2003. 137(1-2):111-120). In one study, the fluoride level increased with the decline in quality of the green tea product (J Agric Food Chem. 2004. 52(14):4472-4476). Interestingly, in low-fluoride water, fluoride is easily released from tea leaves into the beverage. Conversely, in high-fluoride water, dried tea leaves are able also to absorb fluoride. Thus, if a cup of tea is made from high-fluoride water, the fluoride concentration of the infusion may actually be lower than the original fluoride concentration of the water (Sci Total Environ. 2006. 366(2-3):915-917).
Benefits of black tea
Higher tea intake was associated with lower mortality risk in those drinking two or more cups per day in the UK Biobank study, a prospective cohort study of 498,043 men and women. This data is based on a median of 11.2 years of follow up. The statistical benefit was observed independent of genetic variation in caffeine metabolism (Ann Intern Med. 2022. 175. 1201-1211).
Ultraprocessed Foods - see ‘Processed Foods’ section at the bottom of this web page
Vegetables
Many vegetables contain natural toxins which are inactivated by steaming or boiling for a few minutes.
Dr. Andrew Weil specifically recommends against eating rawpeas, chickpeas, beans, alfalfa sprouts, lentil sprouts, mung bean sprouts, and white mushrooms.
Avoid celery with brown patches because they are caused by a fungus which contains natural toxins.
Heating vegetables may destroy the enzymes which help us to digest them; this is the rationale for supplemental digestive enzyme therapy.
Steaming vegetables instead of microwaving them will preserve more of the antioxidants in the vegetables.
Cruciferous vegetables (broccoli, Brussels sprouts, cabbage, cauliflower, collard, kale, radishes, and turnips) probably protect against breast and prostate cancer.
A meta-analysis of 16 prospective studies, ranging from 4.6 to 26 years, found that fruit and vegetable intake was associated with a significantly lower risk of all-cause mortality, with a threshold of approximately 5 servings per day (BMJ. 2014. 349. g4490).
A meta-analysis of 95 prospective studies which included a total of 2 million participants showed that fruit and vegetable consumption was inversely associated with CV disease, cancer, and all-cause mortality in a dose-dependent manner, with maximum health benefit associated with consumption of 6-8 servings per day of fruit and vegetables (Int J Epidemiol. 2017. 46. 1029-1056).
Water
Potential healing benefits of water – this notion is advocated by Dr. F Batmanghelidj, who recommends that all healthy individuals (those without CHF) consume daily approximately 1 ounce of water/kg body weight (1/2 ounce per pound of body weight); he asserts that this high level of daily water consumption can heal allergies, anxiety, asthma, depression, hypertension, migraines, obesity, peptic ulcers, and rheumatoid arthritis.
Safety - for detailed information, navigate to www.drlevyhealthinfo.com/environmental-medicine and scroll about 7/8 down the page
Hard water
Contains magnesium and calcium; prevalent east of the Mississippi River.
Deaths from heart disease are less in locations with hard water.
Artificially softened water is unsafe – the magnesium and calcium are often replaced by sodium when water is artificially softened, and this can leach cadmium out of pipes into the water.
Bottled water
Bottled water is classified as a food and therefore not regulated very well, and is not necessarily safer than tap water.
Aquafina is a brand which is filtered, and thus a good quality brand.
Dasani is a second brand which is filtered and considered good quality
Consumer Reports spot checks in 2019 found that 6% of samples had a contaminant which exceeded state or federal limits (and 7% of community water systems regulated by the EPA had at least one violation of a health-based standard, such as exceeding a contaminant level.
Bottled water sold in soft plastic may be dangerous - there is some concern that chemicals from the plastic leach into the water, especially with repeated use of a plastic water bottle.
Categories of bottled water (NOTE ‘glacier water’ and ‘mountain water’ have no standard definitions)
Artesian – water obtained from a well that taps a confined aquifer (underground layer of rock or sand which contains water).
Distilled – water that has been boiled to kill microbes, then recondensed from steam. Distillation also removes minerals.
Mineral – groundwater that naturally contains at least 250 ppm of dissolved solids
P.W.S. – public water source (i.e. Aquifina and Dasani bottled water)
Purified – water from any source that has been treated to remove chemicals and pathogens; must contain no more than 10 ppm of dissolved solids (i.e. Aquifina and Dasani bottled water)
Sparkling – water that contains carbon dioxide at an amount equal to what it contained when it emerged from the source (i.e. Perrier)
Spring – water derived from an underground formation from which water flows naturally to the Earth’s surface (i.e. Arrowhead, Evian)
Water testing - for detailed information, navigate to www.drlevyhealthinfo.com/environmental-medicine and scroll about 7/8 down the page
Water filters (Consumer Reports. January 2024. Pages 31-33). To choose a water filter effective for specific contaminants (based upon testing of your water supply), go to www.consumerreports.org and search for “water filters.”
There is no water filter on the market which eliminates 100% of all potentially hazardous substances in tap water.
Purchase a water filter which is certified by a third party such as (1) the Water Quality Association (WQA), (2) National Sanitation Foundation (NSF), (3) Canadian Standards Association (CSA), or (4) International Association of Plumbing & Mechanical Officials (IAPMO).
Categories of water filters
Carafe filters are carbon block filters which improve taste and odor, and remove lead, chlorine, and a variety of sediments, but do not remove nitrates, microbial organisms, or pesticides (in 2023, very few are certified to reduce PFAS, but there is data [cited in a January 2024 editorial by Joseph Pizzorno, ND in Integrative Medicine] that “carbon block filters are effective at removing PFAS from the water”). They come as pitchers, and cost $20-$40. Replacement filters cost $40-$100 per year.
Advantages – no installation needed
Disadvantages – filter life relatively short; not suited for households requiring more than a couple of gallons per day of filtered water
Faucet-mounted filters are carbon block filters which improve taste and odor, and remove lead, chlorine, and a variety of sediments, but do not remove nitrates, microbial organisms, or pesticides (in 2023, very few are certified to reduce PFAS, but there is data [cited in a January 2024 editorial by Joseph Pizzorno, ND in Integrative Medicine] that “carbon block filters are effective at removing PFAS from the water”). The filter should be briefly flushed before use because the organic contaminants which build up in the filter provide an ideal breeding ground for bacteria. The filters cost $15-$35. Replacement filters cost $30-$100 per year.
Advantages – easy installation and quick switching between filtered and unfiltered water
Disadvantages – slow rate; filter life relatively short; cannot be used with most pull down or spray faucets
Countertop filters are carbon block filters which improve taste and odor, and remove lead, chlorine, and a variety of sediments. Some also remove nitrates, microbial organisms, or pesticides. In 2023, very few are certified to reduce PFAS, but there is data [cited in a January 2024 editorial by Joseph Pizzorno, ND in Integrative Medicine] that “carbon block filters are effective at removing PFAS from the water.” In 2023, some of the more expensive filters use a combination of carbon block filters, ultraviolet technology, and reverse osmosis to remove a greater range of contaminants. The filter should be briefly flushed before use because the organic contaminants which build up in the filter provide an ideal breeding ground for bacteria. The filters cost $50-$300. Replacement filters cost $50-$100 per year.
Advantages – good at filtering large quantities of water without modification of plumbing; infrequent changes of filter
Disadvantages – flow rate may be slow; cannot be used with most pull down or spray faucets; create countertop clutter
Undersink filters are carbon block filters which improve taste and odor, and remove lead, chlorine, possibly arsenic depending on the brand, possibly PFAS depending on the brand, and a variety of sediments. Some also remove nitrates, microbial organisms, or pesticides. In 2023, very few are certified to reduce PFAS, but there is data [cited in a January 2024 editorial by Joseph Pizzorno, ND in Integrative Medicine] that “carbon block filters are effective at removing PFAS from the water.” In 2023, some of the more expensive filters use a combination of carbon block filters, polypropylene filters, and reverse osmosis to remove a greater range of contaminants. The filter should be briefly flushed before use because the organic contaminants which build up in the filter provide an ideal breeding ground for bacteria. The filters cost $100-$550. Replacement filters cost $50-$150 per year.
Advantages – filters large volumes of water, rarely plugs with sediment; doesn’t clutter countertop, no need to modify faucet, infrequent changes of filter
Disadvantages - generally require installation by a plumber at an installation cost of $120 plus $150, takes up cabinet space; requires a hole in the sink for the dispenser
Refrigerator filters – NOTE one can connect an undersink filter to the fridge and bypass the appliance’s filter
Advantages - improve taste; convenient
Disadvantages - as per Consumer Reports testing are only so-so at removing impurities; replacement filters are costly
Reverse osmosis systems remove chlorine, fluoride, arsenic, lead, nitrates, organic chemicals, microbial organisms, PFAS, pesticides, and even dissolvable substances. These are the most effective means of removing fluoride. Water is flushed through two carbon filters and a synthetic semi-permeable membrane. Reverse osmosis water is very corrosive to metal pipes, so the units should be installed at the tap, not on the main line leading into the house. Cost of the system is about $150-$900 with an additional $300 for installation. The carbon filters need to be replaced yearly, at a cost of $100-$200. The synthetic membrane screen needs to be replaced every 3-5 years at a cost of $100.
Advantages – removes widest range of contaminants, including arsenic
Disadvantages – bulky and requires plumbing modifications, wastes 3-5 gallons of water for every gallon of water filtered; removes beneficial trace minerals from the water; flow rate may be slow; takes up cabinet space; not 100% effective in removing volatile organic compounds (VOC’s) - the reverse osmosis system must be pre filtered by a granularly activated carbon (GAC) filter in order to totally remove the VOC’s.
Yogurt (Consumer Reports. November 2020. Pages 22-25)
Defined by the FDA as a milk product cultured by two specific bacterial species - Lactobacillus bulgaricus and Streptococcus thermophilus.
The bacteria convert the lactose in milk to lactic acid (which is more easily digested than lactose, and thus yogurt may be tolerated even in those with lactose intolerance).
The milk product can be cow’s milk, goat milk or a variety of plant-based milks, including almond milk, cashew milk, coconut milk, oat milk, or soy milk.
Some brands of yogurt are heated after culturing - this inactivates the bacteria (probiotics) used in the culturing process.
Greek yogurt and Icelandic yogurt are strained, and this removes some of the carbohydrate and concentrates the protein, and creates a thicker consistency.
In published studies, regular yogurt consumption is associated with a decreased risk of developing hypertension and diabetes.
Acrylamide (Consumer Reports on Health. 1/03. Is Your Diet Up-To-Date?)
Proven neurotoxin, and a likely carcinogen, found in many plastics.
Identified by Swedish researchers in various fried high carbohydrate foods such as french fries and potato chips at levels far above that allowed in drinking water by the EPA. Subsequent reports indicate high levels in some breads, cereals, and crackers, but with tremendous variability from sample to sample within the same product.
Clinical significance unclear – there is data that acrylamide can inactivate creatine kinase (CK), thereby depleting the body’s energy stores, and also deplete glutathione, an important endogenous antioxidant.
Data in mice indicate that resveratrol (found in red wine and red grapes), tea polyphenols, and diallyl trisulfide (present in processed garlic) inhibit the body’s ability to retain acrylamide (XieQ et al. J Agric Food Chem. 2008. epub).
Data in human liver cells exposed to acrylamide shows that curcumin reduces the production of free radicals, and thus curcumin may mediate acrylamide-mediated genotoxicity (Cao J et al. J Agric Food Chem. 2008. epub).
Advanced glycation end products (AGEs)
Formed by the interaction of a reducing sugar and a protein or an amine containing lipid.
AGEs in food are absorbed intact, persist in tissues, increase the immunogenicity of proteins, promote the development of atherosclerosis and complications of diabetes, promote cross-linking of protein, accelerate the aging process, and increase the inflammatory response.
Cooking methods affect AGE content of food significantly – see just below.
AGE content of typical diet is16,000 kU/day, much higher than optimal.
Fructose is a highly reactive reducing sugar, and therefore promotes the formation of AGEs during cooking. Sucrose is not a reducing sugar. Furthermore, the increase in serum fructose concentrations after ingestion of large amounts of fructose may promote the formation of AGEs in vivo.
Antinutrients (Deanna Minich, PhD. Holistic Primary Care. Summer 2023)
Description (classic) - plant compounds that interfere with the absorption or metabolism of vitamins or minerals.
Description (expanded) - plant compounds that may increase inflammation and gut permeability.
Lectins - large class of proteins within humans, animals, fungi, allergy, plants, and viruses that bind to carbohydrates and in some cases cause agglutination of cells.
Function: Lectins provide a defense system, protecting the animal or plant from pathogens
Much of the data linking lectins to human health risks of come from cell culture and animal studies
While it is unknown, there may be a segment of the population, potentially those with autoimmune conditions, who have greater sensitivity to the potential adverse effects of lectins.
Lectins are water-soluble proteins, so cooking via boiling, steaming, or stewing can reduce the quantity of lectins in the food.
Soaking and fermenting also reduces the quantity of lectins.
However, dry heat cooking and microwaving are not effective at reducing lectin content.
Oxalate - an organic acid that can bind to minerals such as calcium, iron, and magnesium, creating oxalate salts.
Oxalate is synthesized in plants and in mammals.
Unbound oxalates can bind to minerals in the intestine, reducing their absorption.
Oxalate content of plant foods can be modified by cooking methods - boiling and steaming are efficient in decreasing soluble oxalates, with boiling having a greater effect and steaming.
The effect of oxalates on binding minerals can be offset by eating mineral rich foods in conjunction with oxalate rich vegetables.
Phytates (also known as phytic acid or myo-inositol hexaphosphate).
Phytates are a storage form of phosphate and inositol, found in whole grains, legumes, nuts, and seeds.
Phytates bind divalent cations such as iron, calcium, and zinc, preventing intestinal absorption.
Phytate content of foods can be modified by preparation method - soaking, fermenting, and urination can reduce Phytates in foods.
Glucosinolates (goitrogens) Kyolic
Polyphenolic phytoestrogens
Tannins
Cooking methods and health (also see Microwaves below)
Cooking produces cholesterol oxides, lipid peroxides, heterocyclic amines, and advanced glycation end products (see just above).
Cooking method affects advanced glycation end products (AGE) content of food.
Cooking temperature (higher temperature generates more AGEs) – important factor.
Moisture (water inhibits AGE formation) – important factor.
Cooking time (longer time generates only slightly more AGEs) – less important factor.
Microwaving produces relatively few AGEs, but see below for other issues related to microwaving.
Emphasizing boiling, poaching, and stewing over frying, broiling, and roasting may decrease daily AGE intake by up to 50%.
Oven-fried chicken has 9,000 kU of AGEs, whereas boiled chicken has only 1,000 kU of AGEs.
Fast food French fries (100 gm) have1,522 kU of AGEs, whereas a potato boiled for 25 minutes (100 gm) has only17 kU of AGEs.
Roasted walnuts (15 gm) have1183 kU of AGEs, whereas raw walnuts have no AGEs.
Infant formula (100 ml) has 487 kU of AGEs, whereas breast milk (100 ml) has 7 kU of AGEs.
Cookware (also see Microwaves below)
Aluminum – conducts heat well and easy to care for, but aluminum may leach into food, especially acidic food.
Cast iron – iron can leach into the food, especially acidic food, and too much intake of iron can cause health problems (this is an issue primarily for men and postmenopausal women). Enamel coated iron cookware is considered by some to be ideal – it is expensive, and it weighs a lot.
Copper – conducts heat well, but difficult to maintain, and copper may leach into food.
Glass – safest, but does not conduct heat well.
Silicone – nonstick surface, considered safer than Teflon
Soapstone – safe, conducts heat well, BEWARE might crack if exposed to direct flame or wide temperature extremes
Stainless steel – safe, but does not conduct heat well, and some individuals may have allergic reactions to the nickel in stainless steel.
Teflon
Slippery, heat resistant plastic used to coat pans.
When heated to 600 degrees, the coating can break and release perfluorooctanoic acid (PFOA)
In animals, PFOA can cause cancer, immune system damage and death.
95% of Americans have traces of PFOA in their blood – sources include waterproof fabrics and electronic parts as well as Teflon pans.
GOOD NEWS – Consumer Reports (June 2007, pg 7) reports in ‘Up Front’ that testing of air samples showed barely measurable emissions, and that the experts consulted by Consumer Reports agreed that emissions of PFOA from cookware probably don’t contribute much to overall PFOA exposure.
Sensible precautions – discard pans which have begun to flake, use ventilation when cooking, and don’t put empty pans over high heat.
Food Additives
Approximately 2700 food and chemical additives are allowed into the U.S. food supply, including colorings, sweeteners, preservatives, flavorings, emulsifiers, and humectants.
In 1984, 3200 tons of coal tar dyes were added to foods.
The average American eats 14 pounds of food additives per year.
Five food additives to avoid (Consumer Reports on Health. July 2023. Page 2) - brominated vegetable oil, potassium bromate, propyl paraben, Red Dye No. 3, and titanium dioxide, as these five have been linked to serious health problems, such as increased cancer risk, nervous system damage, and behavioral issues.
Aluminum (alum) in baking soda and pickles is best avoided.
Benzoates – may trigger ADHD, allergic rhinitis, asthma, erythema multiforme, urticaria, and vasomotor rhinitis in susceptible individuals
BHA and BHT (synthetic preservatives added to foods to prevent rancidity and thus increase shelf life) may promote carcinogenic changes in cells.
Carageenan (Townsend Letter. July 2011. 89-91)
Food grade carageenan is used to improve the texture of foods (also used in cosmetics, pharmaceuticals, and toothpaste), granted GRAS status by FDA in 1959.
Degraded carageenan is a known carcinogen – there is concern that gastric acid and acid contained in foods, as well as the effects of intestinal flora, may cause degradation of food-grade carageenan into a carcinogen.
Food dyes (Self Healing. 4/09. Pg 7)
The 8 synthetic dyes allowed in the US are Yellow No. 5 (tartrazine) and No. 6, Red No. 3 and No. 40, Blue No. 1 and No. 2, Green No. 3 and Orange B. These are petroleum-based coloring agents.
There are natural alternatives to synthetic dyes, such as beet juice (red) and turmeric (yellow).
There are concerns that synthetic food dyes may be carcinogenic, may cause asthma and hives in adults, and may cause hyperactivity and other behavioral problems in children.
In June 2008, the CSPI petitioned the FDA to ban the 8 approved food dyes.
More information on food dyes and foods containing synthetic dyes at www.iatp.org.
Hydrolyzed vegetable protein, sometimes referred to as just 'vegetable oil' in the ingredients list on the label, contains glutamate and aspartate, both excitatory neurotransmitters which may cause cell death.
Foods which commonly have MSG or hydrolyzed vegetable protein added include soups, salad dressings, steak sauce, croutons, chips, creamy sauces, some gravies, and some gourmet foods.
For more information, read Excitotoxins: The Taste that Kills by Russell L. Blaylock, MD.
Monosodium glutamate (MSG) is a source of excess sodium, and is degraded to glutamate, an excitatory neurotransmitter which in excess may cause death of cells in the brain. In addition, there are case reports of MSG as a trigger for ADHD, asthma, chest pain, depression, epilepsy, fibromyalgia, headaches, perennial rhinitis, and PVCs.
Nitrites which are added to many cured meats can react with protein breakdown products in the digestive tract to form highly carcinogenic nitrosamines. Vitamin C can block the conversion of nitrites to nitrosamines.
Sulfites
May trigger anaphylactic shock, asthma, and urticaria in susceptible individuals.
5-10% of asthmatics experience an exacerbation of symptoms after ingestion of sulfites.
Genetically modified food (GMO)
Soy, corn, canola are the major GMO foods.
Rationale for genetic modification – confers herbicide tolerance, or induces production of a toxin by the plant which kills insects.
Many critics assert that GMO foods have been approved by the U.S. government despite very little human research and some animal research suggesting associated harms.
Genes inserted into GMO crops may be inserted into our DNA or the DNA of our gut bacteria
Observational data - animals avoid eating GMO foods
When a gene is inserted into a plant and then cloned, there might be collateral damage in other genes – in one study, 5% of genes were affected when a gene was inserted
May create a new allergen (new protein)
GMO Soy has increased lectin and lignin content, and is epidemiologically associated with increased likelihood of soy allergy
More information is available in the book Seeds of Deception and at www.seedsofdeception.com and at www.GMFreeSchools.org.
Microwaves
Microwaves heat food by causing it to resonate at very high frequencies - this causes a change in the chemical structure of the food that can lead to health problems.
Microwaving causes the formation of potentially toxic cis-isomers and D-isomers of amino acids.
Microwaving causes the formation of substantial amounts of lipid peroxides.
A study published in the November 2003 issue of The Journal of the Science of Food and Agriculture found that broccoli heated in the microwave with a little water lost up to 97 percent of the beneficial antioxidant chemicals it contains. By comparison, steamed broccoli lost 11 percent or fewer of its antioxidants.
When microwaving food in plastic containers or on paper plates, carcinogenic toxins may be released into the food.
A Turbo Oven is an alternative to a microwave. Food in a Turbo Oven is cooked from all around whereas food in a convection oven is cooked just from above and below.
Organic foods
Popularity – sales of organic food in the US increased from $1 billion in 1990 to $26.7 billion in 2010, according to the Organic Trade Association.
Standardized labels effective 10/21/02, based on guidelines published by the USDA in 2000.
In 1990, Congress passed the Organic Food and Production Act (OFPA), which instructed the USDA to establish uniform national standards for organic food and farming. The 1990 law banned the use of additives and synthetics in organic food.
The USDA issued an initial set of standards in 1997 which would allow for the use of genetically modified crops, irradiation, and sewage sludge in organic food production –much of the organic food industry strongly objected to these specifications.
The USDA 2000 guidelines did not allow for antibiotics, hormones, genetically modified crops, irradiation, or sewage sludge in the production of organic products, but did allow for additives and synthetics, and required only that cows “access to pasture,” an undefined term which is unenforceable, meaning that organic meat and milk most often comes from cows fed corn and soy rather than grass, and cows who spend most of their lives in confinement, similar to the cows on non-organic factory farms.
There are more than 50 organic certification agencies that will ensure that food companies and organic farms meet the new standards, as per Natural Health, Oct/Nov 2002.
Terminology
100% Organic - products produced without bioengineering, radiation, antibiotics, growth hormones, fertilizers, or conventional pesticides. It must be at least 3 years since pesticides were used on the land before food grown on that land can be labeled as organic - if at three years the soil still tests positive for pesticide residues, testing needs to be done yearly and the food cannot be labeled as organic until all pesticide residue is gone from the soil.
Organic - at least 95% of the ingredients must be certified organic.
Made with Organic - at least 70% of the ingredients must be certified organic.
Real Organic Project Seal - nongovernment seal which can be pursued only if a food is USDA certified as organic; means foods must be grown in soli and not water, animals must graze in pastures
Non-GMO Project verified - not USDA regulated, and does not mean the food is organic, but Consumer Reports rates this seal as Excellent for ensuring minimal or no GMO use
Certified Naturally Grown - peer-reviewed certification
Labels which are not USDA regulated and of uncertain validity
Natural
No antibiotics
Consumer priorities for purchasing organic, as suggested by Consumer Reports (July 2022)
Organic produce is a high priority
Organic meat, poultry and eggs are medium priority
NOTE there are not in 2022 any “organic” standards for fish
Pesticide-free
Why choose organic? Organic farming is better for the environment, organic foods have less pesticide, and may be more nutritious.
Safety
A longitudinal 15 day study in 23 children in Seattle age 3-11 concludes that dietary intake of pesticides represents a major source of exposure for infants and children and that an organic diet provides a dramatic and immediate protective effect against exposure to commonly used organophosphate pesticides, which are known to cause neurological effects in some humans (Environment Health Perspect at http://dx.doi.org/ and reviewed in Alt Med Alert. 2006. 9. 11-12).
Non-organic crops most likely to be contaminated with pesticides varies over time. The Environmental Working Group periodically updates its list of “dirty dozen” fruits and vegetables most contaminated with pesticides - for an updated list, go to http://www.foodnews.org/, ‘Food News from the Environmental Working Group’ and scroll to the bottom of the page for a ranking for fruits and vegetables with the most to the least amount of pesticide residue. This list is periodically updated.
Nutritional content – data is MIXED
NEGATIVE study - a systematic review identified 162 studies using one of three designs: field trials (comparing adjacent parcels of land), farm surveys (comparing products from organic and conventional farms), and basket studies (comparing foods available through retail outlets). The authors examined only those nutrient categories reported in at least 10 studies (11 nutrients – vitamin C, phenolics, magnesium, potassium, calcium, zinc, copper, total soluble solids, titratable acid, phosphorous, and nitrogen) or at least 4 livestock studies (ash and unspecified fats). The only differences were that conventional crops contained more nitrogen whereas organic crops contained more phosphorous and titratableacid, and these differences might be due to differences in ripeness or fertilizer use (Dangour AD, et al. Am J Clin Nutr. Epub 7/29/09). The studies identified were heterogeneous and often of poor quality (Greenfield RH. Commentary. Alt Med Alert. 2009. 12. 97-99).
A survey of the literature comparing nutrient content of organic and conventional crops, which used published comparative measurements of organic and conventional nutrient content which were entered into a database for calculation, found that organic crops contained significantly more vitamin C, iron, magnesium, and phosphorus and significantly less nitrates than conventional crops (J Altern Complement Med. 2001. 7(2). 161-73). Some of the original data was presented 2/23/95 by J.B. Pangborn and B. Smith at the 13thAnnual International Symposium on Man and His Environment in Health and Disease, Dallas, TX (cited by Dr. William Rea at IFM International Symposium 4/20/06).
Statistically higher levels of total phenolics were consistently found in organically and sustainably grown foods (blackberries, corn, strawberries) as compared to those produced by conventional agricultural practices (J Agric Food Chem. 2003. 51 (5). 1237 -1241).
Higher levels of polyphenols found in organically grown peaches (Food Chem. 2001. 72. 419-424).
In a study in which tomatoes were grown in a green house, when comparing various flavonoid and carotenoid levels over the course of 12 months, in tomatoes raised organically versus with synthetic fertilizer, the levels were much higher in those raised organically (J Chromatogr A. 2018. 1546. 66-76).
Note toxins (arsenic, cadmium, glyphosate) in the soil have been shown to significantly impair absorption of minerals into plants (Environmental Science and Pollution Research. 2015. 22. 13772-13799).
Health benefits – a systematic review of 7 databases identified 17 studies in humans and 223 studies of nutrient and contaminant levels in foods (Ann Intern Med. 2012. 157. 348-366).
Only 3 of the 17 human studies examined clinical outcomes and these 3 studies found no significant differences in clinical outcomes.
Some studies of vitamin and nutrient levels did show differences; the results were not consistent except for phosphorus (higher levels in conventional produce, a difference of uncertain clinical significance).
The risk for contamination with detectable pesticide residues was 30% lower (CI 23% - 37%) among organic produce.
The risk for isolating bacteria resistant to 3 or more antibiotics was 33% higher (CI 21% - 45%) in conventional produce.
Reduced risk of diabetes - data from NHANES 2007-2010 shows that the odds ratio of those who purchased organic food in the previous month was 0.80, meaning a diagnosis of diabetes was 20% less likely (Nutrients. 2018. 10. 1877).
How to determine quickly if fresh produce is organic – check the Produce Look-Up (PLU) sticker. Organic PLU codes begin with a ‘9’ and have 5 digits.
Why choose ‘local’ produce over organic?
Much organic produce is raised on industrial farms, with conditions similar in many ways to non-organic farms.
Much organic produce is shipped thousands of miles to market, requiring the use of much petroleum to get the food to market.
NOTE in 2005 there are no organic standards for fish.
Reference: When it pays to buy organic. Consumer Reports. 2/06. 12-17.
Prebiotic
Non-digestible food products that provide substrates that nourish the intestinal microflora.
Includes fructo-oligosaccharides (FOS), galacto-oligosaccharides, and inulin.
Food sources of FOS include asparagus, banana, burdock root, honey, Jerusalem artichoke, maple sugar, oats, onion, oats, and rye.
Probiotics – return to Home Page and go to “Dietary Supplements” and scroll to the bottom of the outline
Processed Foods
NOVA classification system
Minimally processed food - may have undergone a procedure like cleaning, freezing, or drying, but not significantly altered from its original form. Examples include eggs, whole grains, some frozen produce, and milk.
Processed foods - contain added ingredients to improve taste or shelf life. Examples include canned products, cured meats, and cheeses
Ultra-processed food (Editorial. Mayo Clin Proc. 2019. 94. 2156-2157) - by definition these foods are made from food constituents but without any identifiable intact food in them.
They often contain coloring chemicals, stabilizing substances, flavoring agents and other additives that imitate or intensify the sensory qualities of foods.
Many ultraprocessed foods contain free sugars, fats, salt, synthetic antioxidants, preservatives, and a variety of other chemical additives.
Examples include sugar-sweetened beverages, sugared milk, fruit drinks, some fast foods such, cookies and candy sweets.
Consumption is widespread across the population because these are tasty, convenient, inexpensive, and with a long shelf life.
Consumption is strongly associated with obesity across multiple countries (Public Health Nutr. 2018. 21. 18-26), and also linked with cancer (BMJ. 2018. 360. k322), and cardiovascular disease ( BMJ. 2019. 365. 11451).
In a prospective cohort of 11,898 individuals in Spain, higher consumption of ultraprocessed foods was associated with higher mortality at a mean follow up of 7.7 years ( Mayo Clin Proc. 2019. 94. 2178-2188).
Some studies indicate that health outcomes are more highly correlated with the overall quality of the diet, rather than consumption of ultra processed foods per se (Time. September 16, 2024. 52-56).
Miscellaneous Facts
There is no single diet or set of rules that is right for everyone.
Some dietary systems conflict totally.
Yoga (India): fresh yogurt and white rice are best, brown rice is worst.
Macrobiotics (Japan): brown rice is best, milk products are worst.
In 1978 in the United States, 36% calories come from fat; in 1994, 34% of calories come from fat. Obesity continues to increase nonetheless. This is in part due to substitution of high glycemic index carbohydrates for fat in the diet.
There is a clear epidemiologic association between obesity and consumption of high fructose corn syrup which is in soda and other prepared foods.
Heart disease is 90% less common in Greece even though the diet approaches 40% fat, presumably because most of the fat is monounsaturated fat (i.e. olive oil).
TYPES OF DIETS AND THE SCIENTIFIC DATA
Low-Carbohydrate (high protein) diets (also referred to as ketogenic diets)
Generally defined as 20-60 gm carbohydrate/day, or approximately 20% of daily calories from carbohydrate).
The theory is that limited carbohydrate will force the body to use stored fat as fuel through ketosis, resulting in loss of fat, and that ketosis will suppress appetite.
Atkins diet (Dr. Atkins’ Diet Revolution, published in 1972), South Beach diet (Agatston, Arthur. The South Beach Diet. 2003), and The Zone diet are low carbohydrate diets.
High protein (low carbohydrate) diets initially produce rapid weight loss through a diuretic effect.
High protein diets are contra-indicated in cirrhosis and other causes of liver failure, as well as advanced kidney disease, and relatively contra-indicated in even mild kidney disease. In a subgroup of the Nurses’ Health Study, high dietary protein intake was associated with a decline in renal function only in women with mild renal insufficiency at baseline (Ann Intern Med. 2003. 138. 460-467).
Health outcomes are a function of what is substituted in the diet for carbohydrate - substituting protein may be associated with worse health outcomes, substituting trans fats is associated with increased total mortality, substituting saturated fats is associated with modestly increased mortality, and substituting monounsaturated and polyunsaturated fats is associated with significant reductions in mortality (JAMA Intern Med. 2016. 176. 1134-1145).
Side effects
In a 6 month prospective trial funded by the Atkins Center, 70% of participants experienced constipation, 65% halitosis, 54% headaches, and 10% hair loss.
According to Dr. Andrew Weil, high protein diets impose a considerable workload on the digestive system and may contribute to feelings of fatigue.
Potential Risks:
May increase the risk of calcium oxalate kidney stones, based on data from a 6 week metabolic study in 10 healthy subjects (Am J Kid Dis. 2002. 40. 265-274).
May increase the risk of osteoporotic fractures in women, based on data in a cohort of 85,900 women followed for 12 years in the Nurses’ Health Study. The association was observed only for animal protein, not vegetable protein (Am J Epidemiol. 1996. 143. 472-479).
Associated with muscle insulin resistance (Wang CC et al. Metabolism. Epub 11/19/12), antioxidant nutrient deficiencies (Br J Nutr. 2011. 106. 282-291) and worsened endothelial function (Hypertension. 2008. 51. 376-382; J Intern Med. 2010. 267. 452-461).
May worsen development of atherosclerosis, through mechanisms independent of known markers (obesity, total cholesterol, triglycerides, glucose, fasting insulin, oxidized LDL, inflammatory cytokines) and may impair neovascularization in response to ischemia, based on data in a mouse model of atherosclerosis (Proc Natl Acad Sci U S A. 2009. 106. 15418-15423 as cited in Alt Med Alert. 2009. 12. 125-126).
May increase all-cause mortality
Analysis 26 years of prospective data from the Nurses’ Health Study (1980-2006) and 20 years of prospective data from the Health Professionals’ Follow-up Study indicates that a low carbohydrate diet based on animal sources is associated with higher all-cause mortality in both men and women, whereas a low carbohydrate diet based on vegetable sources is associated with lower all-cause mortality and cardiovascular disease mortality in both men and women. Diet composition was computed based on data gathered in validated food frequency questionnaires. The accompanying editorial addresses limitations of conclusions drawn from observational data, as opposed to RCT trial data (Ann Intern Med. 2010. 153. 289-298 and editorial 337-339).
Increased cardiovascular and all-cause mortality rates reported in a cohort of Swedish women (J Intern Med. 2007. 61. 575-581).
Dr. Barry Sears argues very low carbohydrate diets are associated with an increase in cortisol so that individuals can break down muscle to create enough glucose for the brain, and that the high cortisol level is the reason individuals regress at 6 months, even if compliant with the diet.
According to Dr. Andrew Weil, high protein diets can aggravate allergies and autoimmune problems.
Potential benefits
Weight loss
A meta-analysis of RCTs comparing the effects of low-carbohydrate diets without energy restriction to low-fat, energy restricted diets, and with at least 6 months of follow-up found that in the 5 trials with a total of 447 participants who met inclusion criteria, weight loss was 3.3 kg greater (1.4-5.3 kg) at 6 months in the low-carbohydrate group, but equivalent in both groups at 1 year. There were no differences in BP between the two groups. At 6 months, triglycerides and HDL changed more favorably in the low-carbohydrate group, but TC and LDL changed more favorably in the low-fat group. A limitation of the analysis was a high dropout rate of 31-48% in the low-carbohydrate trials individuals and 37-50% of the low-fat individuals (Arch Intern Med. 2006. 166. 285-293).
In a 12 month RCT of 148 obese men and women without clinical cardiovascular disease, funded by the NIH and conducted at a large academic medical center, “The low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet.” Strengths of the study include an approximately 80% completion rate in both diet groups, high rates of dietary adherence based on 24-hour recall and measurement of urinary ketone levels, and a substantial proportion of black participants (Ann Intern Med. 2014. 161. 309-318).
In a 12 month RCT of 609 participants without diabetes and with a BMI of 28-40, "there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss" (JAMA. 2018. 319. 667-679).
Increase in HDL (JAMA. 2005. 293. 43-53) – NOTE though that the higher HDL levels noted in the RCTs of the Atkins diet don’t necessarily translate to a lower cardiovascular risk, because the higher dietary cholesterol intake may require a higher HDL level to remove the extra cholesterol from the bloodstream.
Decrease in LDL – compared with low fat diets, low carbohydrate diets were associated with more significant reductions in total cholesterol, LDL cholesterol, and triglycerides, and an increase in HDL cholesterol (Am J Epidemiol. 2012. 176[Suppl]. S44-S54). However, cohort trial data shows an association between low carbohydrate diets and increased cardiovascular and all-cause mortality rates (J Intern Med. 2007. 61. 575-581).
Some individuals with symptoms of hypoglycemia on a high complex carbohydrate diet may feel better on a high protein diet.
Individuals who believe that they have a condition labeled by some health authorities as "chronic yeast syndrome" may find that they feel better on the high protein "MEVY" diet (that is meat, eggs, vegetables, and yogurt).
BEWARE of deceptive labeling (Consumer Reports. 6/04. 12-15)
There is not an agreed-upon definition of low-carbohydrate (the FDA is addressing this)
Net carbohydrates generally refers to the total grams of carbohydrates per serving minus the grams of fiber and sugar alcohols. Research shows that this is a meaningful measurement in whole foods, but there is no research to show that this value is of an significance in designer foods with carbohydrate removed and sugar alcohols or fermentable carbohydrates added. This term currently has no legal standing.
Pay attention to the number of calories per serving on the label, not just the grams of carbohydrate, because some low carbohydrate foods have added fat and thus are loaded with calories.
A nice review article is Very-low-carbohydrate weight-loss diets revisited. Cleveland Clinic Journal of Medicine. 2002. 69. 849-862.
Low Fat (high carbohydrate) diets
Definition: Low-fat diet = less than 30% of total energy intake is derived from lipids; very-low-fat diet = 15% or less of total energy intake is derived from lipids.
The “Ornish diet” is a very-low-fat diet, and is associated with improved cardiovascular outcomes in those with coronary artery disease (but the Ornish protocol/published studies include smoking cessation, regular exercise, and group support, so it is impossible to determine from the published studies the relative importance of each of the specific "ingredients" of the Ornish protocol).
Theoretic advantages – fat is calorie dense (9 kcal/gm versus 4 kcal/gm) and relatively less satiating than protein or carbohydrate (Obes Rev. 2003. 4. 83-90).
Low fat diets can be problematic if simple carbohydrates replace fat – triglycerides will go up and HDL will go down.
The published data on the effectiveness of low fat diets for weight loss, compared with other types of diets, is mixed.
These are NOT associated with better health outcomes - in the Women's Health Initiative Dietary Modification Trial of 48,435 women, at a mean follow up of 8.1 years, those randomized to a low fat diet successfully reduced dietary fat intake by 8.2% of calories consumed, and lowered saturated fat to less than 10% of calories consumed, but health outcomes were the same as health outcomes in those women randomized to a control diet (JAMA. 2006. 295. 655-666).
In the prospective Urban and Rural Epidemiological (PURE) study, data on 135,335 participants in 18 countries shows that high-carbohydrate diets are associated with adverse effects on long-term survival and CV health (Lancet. 2017. 390. 2050-2062).
A systematic review and meta-analysis of 40 RCTs (n = 35,548) of 7 dietary programs concluded that in adults with increased cardiovascular risk, structured dietary programs focusing on low-fat diets reduce all-cause mortality, but not cardiovascular mortality (BMJ. 2023. 380. e0720030).
Low glycemic index or load diets
Resting energy expenditure (measured after a 10 hour fast and after achievement of 10% reduction in body weight) decreased less (p=0.04) with a low glycemic load diet than with a low fat diet, even though body composition by DEXA did not differ between the two groups. The difference in resting energy expenditure between the two groups was 80 kcal/day (1 kg = 7500 kcal). Less hunger also reported amongst those on low glycemic load diet (p=0.04). This means that physiologic adaptations that serve to defend baseline body weight can be modified by dietary composition (JAMA. 2004. 292. 2482-2490).
Most studies report beneficial health outcomes with a low GI/GL diet (Clinical update: the low glycameic-index diet. Lancet. 2007. 369. 890-892).
Insulin resistance, serum triglycerides, CRP levels, and blood pressure improved more with low glycemic load diet, compared with low fat diet (JAMA. 2004. 292. 2482-2490).
Weight loss – data from 6 RCTs indicates that overweight and obese people lose significantly more weight on low GI/GL diets than on other diets (Cochrane Database Syst Rev. 2007. 3:CD005105).
Cardiovascular risk reduction – a 12 week RCT in 129 overweight or obese adults assigned to one of 4 reduced-fat, high-fiber diets (1) 55% carbohydrate, high GI (2) 55% carbohydrate, low GI (3) 25% protein, high GI and (4) 25% protein, low GI found that all groups lost a similar amount of weight, but cardiovascular risk reduction was optimized by high carbohydrate, low GI diet (Arch Intern Med. 2006. 166. 1466-1475).
DASH Diet
Designed specifically as a treatment for hypertension – the diet consists of increased fruits and vegetables and low fat dairy products and lean meat, restricted in saturated fat and total fat intake.
Assessment of diet 7 times over 24 years by FFQ in a cohort of 88,517 nurses in the prospective Nurses’ Health Study, and calculation of a DASH score at each assessment, based on 8 food and nutrient components (fruits, vegetables, whole grains, nuts and legumes, low fat dairy, red and processed meats, sweetened beverages, and sodium) showed that adherence to a DASH-style diet is associated with a lower risk of heart disease and stroke (Arch Intern Med. 2008. 168. 713-720).
In an umbrella review of meta-analyses and systematic reviews of studies including approximately 950,000 participants, greater adherence to the DASH diet was associated with a decreased incidence of cardiovascular disease, coronary heart disease, diabetes, and stroke (Nutrients. 2019. 11. 338).
Intermittent Fasting
Time-restricted eating - food/beverage consumption occurs only during 8-10 hours/day.
Mechanism of action: a metabolic switch from using glucose for metabolism to using fatty acids and ketone bodies for metabolism occurs, with subsequent greater efficiency and energy production.
Cardiovascular disease prevention - mixed evidence (Cochrane Database Syst Rev. 2021. 1. CD013496).
Weight loss - benefit likely drives from the associated reduction in calorie intake.
Mediterranean Diet
Seven principle components of Mediterranean diet include (1) plant based foods, (2) locally grown minimally processed food, (3) fish and poultry, (4) infrequent red meat consumption, (5) olive oil as principle source of fat, (6) moderate amounts of red wine with meals, and (7) desserts primarily of fresh fruit. Of note, “this dietary pattern of eating was not observed until the decade after World War II - an artifact of postwar impoverishment that proved beneficial to health.” (History of Medicine Commentary. N Engl J Med. 2013. 368. 1274-1276).
Protective against a wide variety of health outcomes: An umbrella review of meta-analyses of observational studies and randomized clinical trials, with data from more than 12,800,000 participants indicates that the evidence is robust for a protective association between adherence to the Mediterranean diet and the following health outcomes: Death from any cause, cancer, cardiovascular disease, coronary heart disease, diabetes, myocardial infarction, and neurodegenerative diseases (Eur J Clin Nutr. 2018. 72. 30-43).
Protective against mortality
Studies showing an association between the Mediterranean diet and increased longevity include N Engl J Med. 2003. 348. 2599-2608 and Br J Nutr. 1999. 82. 57-61.
A European cohort study (HALE project) shows that the Mediterranean diet in conjunction with physical activity, nonsmoking status and alcohol in moderation is associated with a 50% reduction in all-cause mortality in those age 70-90 years old (JAMA. 2004. 292. 1433-1439).
A large prospective cohort study, the EPIC-Elderly Prospective Study Group which monitored dietary intake in 74,607 men and women over age 60 in nine European countries, found a clear association between a Mediterranean-style diet (polyunsaturated fats were allowed in place of monounsaturated fats in calculating a score to reflect the Mediterranean diet) and increased survival amongst the elderly (BMJ. 2005. 330. 991-995).
The Mediterranean diet was associated with a reduced all-cause mortality and cause-specific mortality at 5 years of follow up in 214,284 men and 166,012 women in the NIH-AARP Diet and Health Study, a prospective study (Arch Intern Med. 2007. 167. 2461-2468).
Protective against Alzheimer Disease
The Mediterranean diet is associated with a decreased risk of Alzheimer Disease, independent of benefit associated with higher levels of physical activity (JAMA. 2009. 302. 627-637).
Protects against development of Alzheimer’s based on data from a RCT (JAMA Intern Med. 2015. 157. 1094-1103).
Protective against cardiovascular disease
In the Lyon Diet Heart Study, a prospective, randomized, single-blinded study which included 605 participants post first MI, the experimental group consumed a Mediterranean diet which provided 30% of calories from fat but only 8% from saturated fat, 9-11 servings of grains per day, and 5-9 servings of fruits and vegetables per day. Dairy products and red meat were consumed sparingly, but the experimental diet included an omega-3 fatty acid supplemented margarine. The control group consumed a "prudent western-type diet” (a low-fat American Heart Association diet. In the experimental group, plasma levels of vitamin E and vitamin C were increased. After a mean follow up of 27 months, there were 16 cardiac deaths in the control group and 3 in the experimental group; 17 non-fatal MI's in the control group and 5 in the experimental group. The number needed to treat (NNT) with a Mediterranean diet to prevent one cardiovascular event was 12 (Lancet. 1994. 343. 1454-1459).
Studies showing a either a decrease in cardiovascular risk or improvement in risk factors in those following a Mediterranean diet include J Nutr. 2005. 135. 410-415 and Nutr J. 2003. 2. 1 and Am J Clin Nutr. 2004. 80. 1012-1018.
A meta-analysis shows that the Mediterranean diet is associated with a reduced risk of cardiovascular disease, cancer, and mortality (Sofi F et al. BMJ. 2008. 337. a1344).
In the PREDIMED trial, a 3-arm, multicenter, RCT of 7447 individuals who were at high risk of cardiovascular disease at baseline, but with no cardiovascular disease at enrollment, the incidence of major cardiovascular events (composite endpoint, defined as MI, stroke, or death from cardiovascular causes) was reduced in those randomized to the Mediterranean diet group supplemented with extra-virgin olive oil, and also reduced in those randomized to the Mediterranean diet group supplemented with mixed nuts, as compared with those randomized to a control diet (advice to reduce dietary fat).The trial was stopped after a median follow up of 4.8 years, based on interim analysis showing benefit, with hazard ratios of 0.70 (0.54 – 0.92) in the group assigned to the Mediterranean diet group supplemented with extra-virgin olive oil, and 0.72 (0.54 – 0.96) in the group assigned to the Mediterranean diet group supplemented with nuts (N Engl J Med. 2013. 368. 1279-1290). In an accompanying editorial, the authors comment that analysis of the dietary intake of each of the 3 groups in this trial suggests that “the most striking differences between the randomized groups resulted from the supplemental foods” (i.e. extra virgin olive oil versus mixed nuts), and thus the results of this trial seem more a testament to the health benefits of mixed nuts and/or extra virgin olive oil, as opposed to the Mediterranean diet (N Engl J Med. 2013. 368. 1353-1354).
A systematic review and meta-analysis of 40 RCTs (n = 35,548) of 7 dietary programs concluded that in adults with increased cardiovascular risk, structured dietary programs focusing on Mediterranean-style diets reduce all-cause and cardiovascular mortality (BMJ. 2023. 380. e0720030).
Protective against and in treatment of depression
In the SMILES RCT, a modified Mediterranean diet intervention was associated with improvement in those with major depression (as measured with the Montgomery Asberg Depression Rating Scale) compared with a social support intervention (BMC Med. 2017. 15(1). 23).
Lower risk of depression in those consuming a Mediterranean dite, based on several published cohort studies (Arch Gen Psychiatry. 2009. 66(10). 1090–1098; Arch Gerontol Geriatr. 2020. 88. 104022; Aging Clin Exp Res. 2021. 33(4). 1033–1040).
Beneficial in metabolic syndrome, pre-diabetes and diabetes
A 2 year randomized, single-blind trial in 180 patients with metabolic syndrome comparing a Mediterranean-style diet (intervention group) with a "prudent" diet similar in composition to the Step I AHA diet found significantly more weight loss in the intervention group (4 kg vs.1.2 kg, P<0.001), a significantly greater decrease in hs-CRP levels (P=0.01), and greater improvement in endothelial function score (P<0.001). Only 40 of the 90 patients in the intervention group still had features of metabolic syndrome at the end of two years, compared with 78 of 90 patients in the control group (JAMA. 2004. 292. 1440-1446).
A prospective cohort study in Spain found that healthy patients who adhered closely to this diet had a 35% relative reduction in the risk of developing diabetes (BMJ. 2008. 336. 1348-1351).
A 4 year randomized single-center study in 215 overweight individuals newly diagnosed with type II diabetes found that those who consumed a Mediterranean diet had better glycemic control, more favorable changes in coronary risk factors, and a delayed need for antihyperglycemic drug treatment, compared with control subjects who followed a low fat diet (Ann Intern Med. 2009. 151. 306-314).
In a subgroup analysis of individuals in the PERIMED trial who did not have diabetes at baseline, the Mediterranean diet supplemented with extra-virgin olive oil had a significantly lower rate of onset of diabetes at 4 years of follow-up (RR 0.60, 95% CI 0.43 – 0.85, as compared with a control diet), even though calorie intake was not restricted. The group randomized to Mediterranean diet supplemented with mixed nuts had a nonsignificant decrease in rate of onset of diabetes at 4 years of follow up (RR 0.80, 95% CI 0.61 – 1.10) [Ann Intern Med. 2014. 160. 1-10].
In 8.1 year follow up of a RCT of 215 newly diagnosed type II diabetics, a low-carbohydrate Mediterranean diet was associated with delayed start of glucose lowering medications, as compared with a low-fat diet (Diabetes Care. 2014. 37. 1824-1830).
A systematic review and meta-analysis reported that a Mediterranean-style dietary pattern was associated with improved glycemic control and normalization of immune biomarkers (Adv Nutr. 2019. 10. 433-451).
Mediterranean diet is associated with a markedly lower risk of gestational diabetes, eclampsia, and preeclampsia based on a large cohort study of nearly 8000 geographically, racially, and ethnically diverse US women - 21% reduction in adverse pregnancy outcomes among women who closely followed a Mediterranean diet (Makarem N et al. JAMA Network Open. 2022).
Other benefits
Greater adherence to the Mediterranean diet is associated with longer telomere length (telomere length correlates with aging), based on data in 4676 healthy women from nested case control studies within the Nurses’ Health Study (BMJ. 2014. 349. G6674).
In a RCT of 250 men and women with newly diagnosed diabetes assigned to a Mediterranean diet or a low fat diet, at 8.1 years of follow up the mean decline in a score of sexual function was less in those following the Mediterranean diet (J Diabetes Complications. 2016. 30. 1519-1524).
In two Swedish cohort studies (n= 37,903 men and 33,403 women) adherence to the Mediterranean diet was associated with a lower risk of hip fracture (J Bone Miner Res. 2016. 31. 2098-2105).
Those who followed a Mediterranean diet had a 28% lower risk of fatal cancers, as compared with those who didn’t follow a Mediterranean diet (Mayo Clin Proceedings. Aug 16, 2023).
Negative data
Some meta-analyses and systematic reviews of RCT intervention trials generally do not affirm the benefits reported in epidemiologic studies (Am J Clin Nutr. 2018. 107. 389-404; Eur J Clin Nutr. 2022. 76. 1060-1072).
See negative trial of MIND diet just below.
MIND diet (Mediterranean-DASH Intervention for Neurodegenerative Delay)
Negative trial: in the “Trial of the MIND diet for prevention of cognitive decline in older persons, a 3-year RCT of 604 older adults without cognitive impairment but with a family history of dementia, the groups did not differ at 3 years in terms of brain MRI outcomes or changes in cognition. The MIND diet is a hybrid of the DASH diet and the Mediterranean diet (N Engl J Med. 2023. 389. 602-611).
Paleolithic diet
Emphasizes plentiful consumption of vegetables, fruits, nuts, eggs, and lean meats; excludes dairy, legumes, and cereal grains (as these did not become part of the human diet until 10,000 years ago).
Outcomes data from long term RCTs are lacking (in 2013).
Benefits – improved blood pressure, improved glucose tolerance, decreased insulin secretion, increased insulin sensitivity, and improved lipid profile, even in the absence of weight loss (Frassetto LA et al. Eur J Clin Nutr. 2009. 63. 947-955).
Vegan diet - excludes all foods and beverages derived from animals (vegetarian as just below + no eggs + no milk products)
May be more effective than omnivorous diets at improving blood sugar, blood lipid values, and BMI (Crit Rev Food Sci Nutr. 2015. 55. 2004-2013; Crit Rev Food Sci Nutr. 2017. 57. 3640-3649).
A meta-analysis of 11 RCTs (n = 983) indicates that a vegan diet does not result in a lower BP when compared with less restrictive diets for HTN such as the DASH diet (Am J Med. 2019. 132. 875-883).
This finding was unexpected based on a meta-analysis of 7 clinical trials and 32 observational trials which showed that a vegetarian diet was associated with BP reduction 5-7 mm Hg lower than that found in omnivorous individuals (JAMA Intern Med. 2014. 174. 577).
Subgroup analysis by baseline systolic BP did show that in those with a baseline systolic BP > 130 mm Hg, vegan diet did reduce systolic and diastolic BP 4 mm Hg beyond the comparison group.
Vegetarian diet (lacto-ovo-vegetarian diet)
Greater adherence to a vegetarian diet is epidemiologically associated with a decreased risk of certain types of cancer, cardiovascular disease, diabetes, diverticulosis, dyslipidemia, gallstones, high blood pressure, ischemic heart disease, osteoporosis, and stroke (Nutr Rev. 2009. 67. 255-263; Crit Rev Food Sci Res. 2017. 57. 3640-3649; BMC Med. 2022. 20. 79; Eur J Nutr. 2023. 62. 51-69).
Vegetarian diet and mortality in prospective cohort studies
A pooled analysis 5 cohorts, including more than 76,000 men and women with an average follow up of 10.6 years, did find a reduced risk of CV mortality, RR=0.76 (Key TJ et al. Am J Clin Nutr. 1999. 70[Suppl]. S516-S524).
In the Oxford Vegetarian Study in 6000 vegetarians and 5000 nonvegetarians, at 12 years of follow up, vegetarians had a lower total mortality (RR=0.80) and a lower mortality from malignant neoplasms (RR=0.61), with a nonstatistically significant trend toward lower cardiovascular mortality (Appleby PN et al. Am J Clin Nutr. 1999. 70[Suppl]. S525-S531).
The American Dietetic Association published a position paper stating that appropriately planned vegetarian diets are healthful, nutritionally adequate, and provide health benefits in the prevention and treatment of certain diseases (J Am Diet Assoc. 2003. 103. 748-765).
Approximately 2.5% of adults in the U.S. follow vegetarian diets.
Vegetarians tend to have a lower BMI than non-vegetarians.
Adequate carnitine can be a problem, especially in children who are strict vegetarians – this amino acid is essential for conversion of fat into energy (i.e. ATP)
Adequate iodine intake can be a problem if non-iodized salt is used – seaweed and kelp are good vegetarian sources of iodine.
Adequate iron intake can be a problem.
Heme iron in meat is 15-35% absorbed; non-heme iron is 1-7% absorbed. However, digestion in long-term vegetarians may adjust to allow increased percentage of iron absorption.
Absorption of non-heme iron, predominantly found in dark green, leafy vegetables, may be increased up to 5-fold by vitamin C (eat fruits with vegetables).
Iron content of the diet can be increased 4-fold by using iron pots and skillets.
Absorption of heme iron is usually unaffected by the rest of the diet, but absorption of non-heme iron is hindered by caffeine, tea (tannic acid and polyphenols), and phytates found in many legumes and grains
Iron probably competes with other minerals for binding sites at the intestinal wall, so supplements of any one mineral may lead to decreased absorption of other minerals (iron, calcium, copper, zinc, selenium).
Adequate lysine intake can be a problem – lysine is plentiful in legumes, but relatively deficient in wheat.
Adequate omega 3 fatty acid intake can be problematic – consider supplements. There are vegan supplements of DHA made from microalgae; these are expensive.
Adequate taurine (an amino acid) can be problematic – this conditionally essential amino acid which is essential for detoxification/biotransformation is absent in all vegetable protein.
Adequate vitamin B12 intake can be a problem in vegans who do not take supplements. Measuring vitamin B12 levels can be deceiving because vegetarian diets may contain vitamin B12 analogues which will cause a false normal vitamin B12 level (measure MMA). In some vegans, the bacteria in the mouth and the colon make enough vitamin B12 so that deficiency is avoided.
Adequate zinc intake can be a problem, especially at the time of conversion to a vegetarian diet, probably because the intestinal phytase required to break down phytic acid and thus allow absorption of calcium, iron, etc. from fiber, is a zinc dependent enzyme. Zinc supplements, 15-20 mg/day, are probably advisable at the time of transition to vegetarianism.
Foods to include in a vegetarian diet (Natural Solutions. 1/09)
Almond butter -good source of protein, calcium, iron, and zinc.
Miso - fermented soy product which is loaded with protein, iron, and vitamin K.
Nutritional yeast - natural source of vitamin B12.
Quinoa - source of all 8 essential amino acids, good source of iron and zinc, high protein content (truly a seed and not a grain).
Pumpkin seeds - good source of iron and zinc.
Sunflower seeds - good source of iron and zinc.
Tempeh - fermented soy product which is loaded with protein.
Wheat germ - good source of iron and zinc
Resource: Vegetarian Resource Group www.vrg.org.
Diet and cancer (Arch Intern Med. 1993. 153. 50-56)
Experimental data
Increased fat intake is associated with an increased risk of cancer in animal models.
Increased calorie intake is associated with increased risk of cancer.
Linoleic acid intake is associated with increased risk of cancer.
A wide variety of dietary substances exhibit anti-carcinogenic activity in animal models, including vitamins A, C, E, beta-carotene, calcium, selenium, some forms of fiber, and CLA, which is a class of fatty acids closely related to linoleic acid, which are found in dairy products, ruminant animal meat, and turkey.
High dose anti-oxidants in supplemental form may have a paradoxical carcinogenic effect.
Pickled and smoked foods as they are prepared in the United States are probably not carcinogenic. Different methods of food preservation in other countries may be responsible for contamination of food with carcinogens.
Pesticides: intake of man-made pesticides in the U.S. is 0.09 mg/person/day, 50% of which is due to 4 chemicals that are not carcinogens, but intake of natural pesticides is about 1.5 gm/person/day, and many are known carcinogens. Furthermore, stress, such as that induced by insect attacks on plants, leads to an increase in natural pesticide production in plants.
Epidemiologic data
Increased fruit and vegetable consumption is linked with reduced cancer risk. The reasons are not fully known.
Except for the recent National Cancer Institute study of 30,000 Chinese, no other studies document an epidemiologic association between fat consumption and cancer.
Micronutrient Nutrition
Vitamins and minerals – Go back to Home Page and click on “Vitamins and Minerals” for details
Phytochemicals – scientific appreciation of the health benefits of phytochemicals (chemical compounds found in plants) is a much more recent phenomenon than the scientific appreciation of the health benefits of vitamins and minerals.
There may be as many as 1000 different phytochemicals, with over 500 phytochemicals identified in fruits, vegetables, and grains as of 2005
Many of these phytochemicals have more than one function in the body.
Phytochemicals for which dietary intake is associated with health benefits
Allicin - reduced risk of cancer spread and heart attacks, lower cholesterol and blood pressure, enhance infection defenses.
Found in garlic, leeks, white onions.
Anthocyanins (a category of flavonoids) - decrease blood clots, improve night vision, combat macular degeneration, lower blood pressure, and may protect against age related changes in the brain.
Found in beets, bilberries, blackberries, black currants, blueberries, cranberries, elderberries, kidney beans, purple grapes, raspberries, red apples, red cabbage, red onions, strawberries, sweet cherries.
One 8 ounce glass of purple grape juice may be as effective as aspirin at preventing a heart attack.
Beta carotene – reduced risk of cancer and heart disease, increased ability to fight infection, maintenance of good vision.
Found in apricots, butternut squash, cantaloupe, carrots, mangos, peaches, pumpkin, sweet potatoes.
Capsaicin - painkiller, anticancer effects.
Found in chili peppers.
Carotenoids – family of pigments (more than 600 now identified), including alpha carotene, beta carotene, lutein, lycopene, zeaxanthin.
Catechins - decrease oxidation of LDL cholesterol, and may decrease cancer risk. Catechins are flavonoids
Found in green tea, and in smaller quantities in black tea.
Curcuminoids – polyphenols from turmeric, anti-inflammatory effects.
EGCG – see ‘tea’ above, and specifically benefits of green tea. EGCG is a flavonoid.
Ellagic acid – in pomegranate, anticancer effects
Found in raspberries, strawberries.
Flavonoids (subgroup of plant polyphenols; approximately 4000 flavonoids have been identified (Nutrients. 2014. 6. 6020-6047).
Large body of research documenting reduction in quantity in the food supply over the past few decades (Pizzorno, Joseph, ND. Integr Med. 2023. 22[3]. 6-9).
Storage - storing uncut vegetables in the refrigerator (in the dark) results in no significant loss of flavonoid content.
Food preparation - microwaving has the least damaging impact on flavonoid content of foods.
Consumption - consuming the food in unprocessed form as soon as possible after harvest maximizes intake of flavonoids from the food.
Glutathione - antioxidant and anti-cancer properties.
Found in asparagus, avocado, broccoli, cauliflower, fresh grapefruit, okra, fresh oranges, fresh peaches, white potatoes, squash, strawberries, raw tomatoes, and watermelon.
Indoles - antioxidant properties, reduced risk of breast and prostate cancer.
Found in arugala, broccoli, brussels sprouts, cabbage, cauliflower, horseradish, kale, mustard, radish, Swiss chard, turnip, and watercress.
Isoflavones (a category of flavonoids) - phytoestrogens which combat menopausal symptoms, strengthens the bones, lowers cholesterol levels, raises HDL cholesterol levels, and may decrease cancer risk.
Found in some soy products, including raw soybeans, soy milk, soy nuts, tempeh, and tofu. Not present in soy sauce, soy oil, or in many brands of soy burgers, soy cheeses, or soy hotdogs.
Soy protein is probably a surrogate marker for isoflavones, with 20 - 60 grams per day of soy protein recommended for maximum benefit.
Lutein (a carotenoid) - antioxidant properties, reduced risk of cataracts and macular degeneration, reduced risk of colon cancer.
Found in broccoli, green peas, honeydew, kale, kiwi fruit, leafy greens, romaine lettuce, and spinach.
Lycopene (a carotenoid) - antioxidant properties, anti-cancer properties.
Found in pink grapefruit, guava, tomatoes, and watermelon.
Phenolics – slow effects of aging.
Found in eggplant, plums, prunes, raisins.
Polyphenols - family of more than 800 compounds, and over 10,000 have been structurally identified (Nutrients. 2014. 6. 6020-6047)
Heart protective benefits and anti-cancer properties.
Polyphenols have demonstrated the ability to regulate the neuroendocrine system, based in part on their plant-based chronobiotic properties (Minich, Deanna. Integr Med. 2024. 23[1]. 28-31).
Extent of metabolism of the polyphenols in grapes is in part a function of light exposure, based on a rat study.
Animal studies show that when a variety of fruits are consumed at times of the year when they cannot be harvested locally, there is increased fat accumulation.
Found in red wine, red grapes, cranberries, dark chocolate, nonherbal teas (black, green, white, and oolong).
Polyphenols are divided into 6 categories, as per the Linus Pauling Institute
Anthocyanins – see above.
Flavanols - food sources include apples, apricots, green tea, red grapes, red wine
Flavanones - food sources include citrus fruits and juices
Flavonols - food sources include apples, blueberries, broccoli, cranberries, kale, leeks, onions
Flavones - food sources include celery, hot peppers, parsley, thyme
Isoflavones – see above.
Proanthocyanidins – polyphenols found in grape skin, pine bark, and cocoa; anti-inflammatory and antioxidant effects
Quercetin - flavonoid with antioxidant properties.
Found in broccoli, cherries, red grapes, yellow and red onions, and Italian yellow squash.
Resveratrol – a polyphenol in grape skin, peanut skin and red wine which lowers CRP, has anti-aging effects, improves insulin sensitivity, might lower blood pressure, and might improve cognitive function in seniors
Sulforaphane - anti-cancer properties.
Found in bok choy, broccoli, Brussels’ sprouts, cabbage, and cauliflower.
References
Agatston, Arthur. The South Beach Diet
Ballentine, Rudolph. Transition to Vegetarianism
Ballentine, Rudolph. Diet and Nutrition
Batmanghelelidj, F. Your Body’s Many Cries for Water
Blaylock, Russell L. Excitotoxins: The Taste that Kills
Brand-Miller, Jennie et al. The New Glucose Revolution
Campbell, T. Colin. The China Study
Carper, Jean. Food-Your Miracle Medicine
Daniel, Kayla. The Whole Soy Story
Enig, Mary. Know Your Fats
Erasmus, U. Fats that Heal, Fats that Kill
Falon, Sally. Eat Fat, Lose Fat
Falon, Sally. Nourishing Traditions
Galland, Leo. The Fat Resistance Diet
Keston, Deborah and Larry Scherwitz. Whole Person Integrative Eating
Kushner, RF and Kushner N. Dr. Kushner’s Personality Type Diet
Nedrow, Bonnie. Metabolic Flexibility: How to Use the Ketogenic Diet to Heal Your Metabolism
Nestle, Marion. What to Eat
Pollan, Michael. The Omnivore’s Dilemma
Price, Weston. Nutrition and Physical Degeneration
Pratt, Steven and Kathy Mathews. Superfoods Rx: Fourteen Foods That Will Change Your Life
Quinn, Sheila (ed). Clinical Nutrition: A Functional Approach
Rolls, Barbara and Barnett RA. The Volumetrics Weight Control Plan
Sanders, Lisa. The Perfect Fit Diet
Sears, Barry. The Anti-Inflammation Zone
Weil, Andrew. Eating Well for Optimum Health
Willett, Walter. Eat, Drink, and Be Healthy
Consumer Reports. 1/90. 27 - 40. Fit to Drink?
Hippocrates. 5/94. 30-37. The Man Who Has a Beef With Your Diet.
Consumer Reports on Health. 1/03. Is Your Diet Up-To-Date?
Consumer Reports. 1/03. 33-38. Clear Choices for Clean Drinking Water.
www.aicr.com. American Institute of Cancer Research web site with abundant information on a healthy diet.
https://www.supertracker.usda.gov/default.aspx. Government page which includes nutrition information on more than 8,000 foods, recommended by Consumer Reports.
Resources
Dr. Leo Galland’s Drug-Nutrient Interactions Workshop Software from Allergy Research Group 800-545-9960 www.allergyresearchgroup.com
Weight, Activity, Variety, and Excess (WAVE) tool – facilitate dialogue between physician and patient; formatted as a pocket card with assessments on one side and recommendations on the other side http://outside.utsouthwestern.edu/chn/naa/wave/wave_instruct.htm (Diabetes Educ. 2001. 27. 352-358)
Rapid Eating and Activity Assessment for Patients (REAP) assesses dietary intake related to 2005 dietary guidelines (J Nutr. 2003. 133. 556S-562S)
National Heart, Lung, and Blood Institute interactive menu planning guide http://hin.nhlbi.nih.gov/menuplanner/menu.cgi
University of Wisconsin Integrative Medicine www.fammed.wisc.edu/integrative/modules Patient Handouts on “The Anti-Inflammatory Diet” and “Detoxification Program: 7 Day Appendix, pages 1-2
Page Updated November 15, 2024