February 22, 2006


A dissident view on the Womens Health Initiative (WHI) Report of 2006


by William Harris, M.D.


Howard BV, Van Horn L, et. al. Low-fat dietary pattern and risk of cardiovascular disease: the Women's Health Initiative Randomized Controlled Dietary Modification Trial. JAMA. 2006 Feb 8;295(6):655-66.


Over a mean of 8.1 years, a dietary intervention that reduced total fat intake and increased intakes of vegetables, fruits, and grains did not significantly reduce the risk of CHD, stroke, or CVD in postmenopausal women and achieved only modest effects on CVD risk factors..


As reported by the New York Times and other media outlets, this expensive study seemed to destroy the idea that low fat diets are protective. However many vegetarian authors commented that this NIH effort was not really low fat. 20% of Calories from fat was recommended but only a reduction to 29% was achieved by the participants. The study did not include vegan women but omnivores who were also consuming the other adverse components of the Standard American Diet. So this $half billion study attempted to salvage a dietary train wreck by re-railing the caboose.

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 However, the idea of low fat diets to avoid various diseases emerged from the ecological studies of Ancel Keys (1/26/1904- 11/20/2004) in 1956 and in 1975 by Carroll KK and Khor HT who produced charts showing increased rates of breast, colon, and prostate cancer with increasing Calorie, fat, and protein intake, country by country. These studies relied on Food and Agriculture Organization (FAO) data for fat intake. However the FAO only reports fat, carbohydrate, and protein intake from plant and animal sources (plus intakes of calcium, iron, and sugar). That gives us 6 categories of macronutrient data but in most cases does not distinguish naturally occurring plant fat from refined vegetable oils and the damaging trans fats made from them.


A recent USDA report (http://www.ers.usda.gov/data/foodconsumption/spreadsheets/nutrients.xls #Foodgroups!a1) indicates that fats and oils account for 22.7% of US Calorie intake.

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I agree that refined fats and oils have detrimental health effects since they are almost 100% of Calories from fat, mostly Linoleic (LA) rather than Alpha-linolenic (ALA) and contain no fiber to retard digestion and absorption. Another 18.9% of US Calories come from sugar and sweeteners, also a train wreck, but evidently not a target of the WHI.


It is not easy to find consumption data for raw nuts and seeds. However, the USDA reports only 3% of yearly US calorie intake from legumes, nuts, and soy. If that is so and we make the generous assumption that 1/3 of those Calories actually are from nuts and further that half of the nut Calories are from raw nuts, then their contribution to U.S. Calorie consumption is only .5% which is only 2.3% of the Calorie contribution from the fats and oils. This is probably already an overestimate since most nuts are consumed as snacks according to http://www.ers.usda.gov/publications/ FoodReview/May2001/FRV24I2i.pdf and snack nuts are almost invariably roasted, often in oil, and frequently salted, to make the insult complete.

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There is no indication that Carroll, Keys, Khor, or Wynder distinguished between oils and naturally occurring plant fats. I obtained Acrobat copies of their papers of 1975 and 1980 from www.medblue.com. A text search on the word avocado was negative. Nuts and seeds are mentioned only when followed by the word oil. But later writers set the low fat dogma in granite that consumption of any kind of fat is bad, and that fat consumption must be kept to a minimum at all cost.


However, every cell membrane in both plants and animals is made of fat (in the form of phospholipids). Because fat is insoluble in water, it's the substance that segregates the organized biochemical activities within the cell from the chaotic ones outside, so without fat there would be no life on Earth. There is no reason to think that human cell membranes don't need replenishment by dietary fat, which is also important for the absorption of carotenoids, calciferol, calcium, manganese, iron, and zinc.


If you are healthy and comfortable consuming a low fat vegan diet by all means stick with it. However, if you find that 10% fat is too restrictive, be aware that at least 37 out of 39 peer- reviewed studies report only beneficial results from the human consumption of avocados (88.1% fat), raw nuts, and seeds (50-90% fat).


I think that the same brush that was appropriately used to tar and feather animal fat and processed fat was accidently applied to naturally fat plant foods, without regard to their many valuable nutrients and protective fiber content. The vegan diet is already restrictive, so universal fat limitation may have scared off some potential vegans and discouraged others who already are.


At least three researchers have had great success reversing coronary heart disease, with a low-fat vegan diet. But it's my suspicion they would have achieved the same results and better patient compliance by relaxing the intake of natural plant fats. In addition, one of them would not have had to include fish in his dietary advice, since avocados, nuts, and seeds are a good source of alpha-linolenic acid, the first of the omega-3 fatty acids.


In short, it's my opinion that animal source foods, processed oils, and sugar are the bad guys and that future dietary studies searching for health improvements should focus on whole food vegans without concern over fat intake as long as its from avocados, raw nuts, and seeds.


Refs:


Probable origin of the low fat theory:


Carroll KK, Khor HT. Dietary fat in relation to tumorigenesis. Prog Biochem Pharmacol. 1975;10:308-53.


Reddy BS, Cohen LA, McCoy GD, Hill P, Weisburger JH, Wynder EL. Nutrition and its relationship to cancer. Adv Cancer Res. 1980;32:237-345.


Nut References


Positives (30):


Am J Clin Nutr. 2002 Nov;76(5):1000-6. Effect of diets enriched in almonds on insulin action and serum lipids in adults with normal glucose tolerance or type 2 diabetes. Lovejoy JC, Most MM, et al


Am J Epidemiol. 2004 Nov 15;160(10):961-8. A prospective cohort study of nut consumption and the risk of gallstone disease in men. Tsai CJ, Leitzmann MF, et al.


Am J Clin Nutr. 2003 Jun;77(6):1379-84. Serum lipid response to the graduated enrichment of a Step I diet with almonds: a randomized feeding trial. Sabate J, Haddad E, et al.


Am J Clin Nutr. 2004 Jul;80(1):76-81. Frequent nut consumption and decreased risk of cholecystectomy in women. Tsai CJ, Leitzmann MF et al.


Am J Clin Nutr. 2001 Jul;74(1):72-9. Effects of walnut consumption on plasma fatty acids and lipoproteins in combined hyperlipidemia. Almario RU, Vonghavaravat V et al.


Angiology. 2003 Jul-Aug;54(4):411-4. Antihypertriglyceridemic effect of walnut oil. Zibaeenezhad MJ, Rezaiezadeh M et al.


Ann Intern Med 2000 Oct 17;133(8):659. Substituting walnuts for monounsaturated fat improves the serum lipid profile of hypercholesterolemic men and women. A randomized crossover trial. Zambon D, Sabate J et al.


Arch Intern Med Jul 1992, 152 (7) p1416-24. A possible protective effect of nut consumption on risk of coronary heart disease. Fraser GE; Sabate J et al.


Asia Pac J Clin Nutr. 2004;13(Suppl):S33. Nuts for cardiovascular protection. Strahan TM.


Br J Nutr. 2004 Sep;92(3):533-40. Long-term almond supplementation without advice on food replacement induces favourable nutrient modifications to the habitual diets of free-living individuals. Jaceldo-Siegl K, Sabate J, et al.


Cancer Epidemiol Biomarkers Prev. 2004 Oct;13(10):1595-603. Association of nut and seed intake with colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition. Jenab M, Ferrari P, et al.


Circulation. 2004 Apr 6;109(13):1609-14. A walnut diet improves endothelial function in hypercholesterolemic subjects: a randomized crossover trial. Ros E, Nunez I, Perez-Heras A, et al.


Circulation. 2002 Sep 10;106(11):1327-32. Dose response of almonds on coronary heart disease risk factors: blood lipids, oxidized low-density lipoproteins, lipoprotein(a), homocysteine, and pulmonary nitric oxide: a randomized, controlled, crossover trial. Jenkins DJ, Kendall CW,et al


Diabetes Care. 2004 Dec;27(12):2777-83. Including Walnuts in a Low-Fat/Modified-Fat Diet Improves HDL Cholesterol-to-Total Cholesterol Ratios in Patients With Type 2 Diabetes.

Tapsell LC, Gillen LJ et al


Br J Nutr. 2004 Sep;92(3):533-40. Long-term almond supplementation without advice on food replacement induces favourable nutrient modifications to the habitual diets of free-living individuals. Jaceldo-Siegl K, Sabate J, Rajaram S, Fraser GE.


Effect of a diet high in monounsaturated fat from almonds on plasma cholesterol and lipoproteins. Spiller GA; Jenkins DJ; et al.


Effects of walnut consumption on plasma fatty acids and lipoproteins in combined hyperlipidemia. Rogelio U Almario, Veraphon et al


Eur J Clin Nutr. 2002 Jul;56(7):629-37. Serum lipid profiles in Japanese women and men during consumption of walnuts. Iwamoto M, Imaizumi K, et al.


Int J Obes Relat Metab Disord. 2003 Nov;27(11):1365-72. Almonds vs complex carbohydrates in a weight reduction program. Wien MA, Sabate JM, et al


Int J Vitam Nutr Res. 2002 Oct;72(5):341-7. Effects of walnut consumption as part of a low-fat, low-cholesterol diet on serum cardiovascular risk factors. Morgan JM, Horton K et al


J Am Coll Nutr Apr 1992, 11 (2) p126-30 A possible protective effect of nut consumption on risk of coronary heart disease. The Adventist Health Study. Fraser GE; Sabate J; et al.


J Lipid Res. 2001 Dec;42(12):2069-76. Walnut-enriched diet increases the association of LDL from hypercholesterolemic men with human HepG2 cells. Munoz S, Merlos M et al.


J Nutr. 2002 May;132(5):1062S-1101S. The scientific evidence for a beneficial health relationship between walnuts and coronary heart disease. Feldman EB.


J Am Coll Nutr. 2003 Jun;22(3):195-200. Effects of plant-based diets high in raw or roasted almonds, or roasted almond butter on serum lipoproteins in humans. Spiller GA, Miller A, et al.


 J Nutr. 2002 Apr;132(4):703-7. Almonds and almond oil have similar effects on plasma lipids and LDL oxidation in healthy men and women. Hyson DA, Schneeman BO, Davis PA.


J Am Coll Nutr. 2003 Apr;22(2):133-41. Peanut consumption improves indices of cardiovascular disease risk in healthy adults. Alper CM, Mattes RD.


J Am Coll Nutr. 2003 Jun;22(3):195-200. Effects of plant-based diets high in raw or roasted almonds, or roasted almond butter on serum lipoproteins in humans. Spiller GA, Miller A, et al.


J Am Coll Nutr. 1992 Apr;11(2):126-30. Effect of a diet high in monounsaturated fat from almonds on plasma cholesterol and lipoproteins. Spiller GA, Jenkins DJ, et al


 J Am Coll Nutr. 1998 Jun;17(3):285-90. Nuts and plasma lipids: an almond-based diet lowers LDL-C while preserving HDL-C. Spiller GA, Jenkins DA, et al


J Nutr. 2005 Sep;135(9):2082-9. A systematic review of the effects of nuts on blood lipid

profiles in humans. Mukuddem-Petersen J, Oosthuizen W, Jerling JC.


Nut and Peanut Butter Consumption and Risk of Type 2 Diabetes in Women. Rui Jiang, MD; JoAnn E. Manson, MD; Meir J. Stampfer, MD; Walter C. Willett, MD, DrPH; et al


Prog Cardiovasc Nurs. 2004 Spring;19(2):73. The effect of combining plant sterols, soy protein, viscous fibers, and almonds in treating hypercholesterolemia. Jenkins DJ, Kendall CW, et al


Negatives (2):


Biosci Biotechnol Biochem. 2002 Jan;66(1):141-6. Differential effect of walnut oil and safflower oil on the serum cholesterol level and lesion area in the aortic root of apolipoprotein E-deficient mice. Iwamoto M, Kono M, et al

This was a negative study using lab mice


Am J Clin Nutr. Vol. 80, No. 6, 1487-1491, December 2004. Butter and walnuts, but not olive oil, elicit postprandial activation of nuclear transcription factor B in peripheral blood mononuclear cells from healthy men. Cecilia Bellido, Jos Lpez-Miranda et al.


Avocado References:


Effect of a high-monounsaturated fat diet enriched with avocado in NIDDM

patients. Lerman-Garber I; Ichazo-Cerro S et al. Diabetes Care Apr 1994, 17 (4) p311-5


Effects of avocado on the level of blood lipids in patients with

phenotype II and IV dyslipidemias. Carranza J; Alvizouri M et al. Arch Inst Cardiol Mex (MEXICO) Jul-Aug 1995, 65 (4) p342-8


Effects of avocado as a source of monounsaturated fatty acids on plasma

lipid levels. Alvizouri-Munoz M; Carranza-Madrigal J et al. Arch Med Res (MEXICO) Winter 1992, 23 (4) p163-7,


 Persin a novel agent from avocado (Persea americana) which has the potential to suppress lactation and destroy mammary tumor cells in vivo Oelrichs P.B., Ng J.C., Seawright A.A., et al (1995) -. Proceedings: 33 International congress on forensic (TIAFT) and 1st on environmental toxicology "Gretox 1995", Thessaloniki, Greece. 27-31 August 1995.


Inhibition of prostate cancer cell growth by an avocado extract: role of lipid-soluble bioactive substances. Lu QY, Arteaga JR, et al. J Nutr Biochem. 2005 Jan;16(1):23-30.


Trypanocidal constituents in plants 5. Evaluation of some Mexican plants for their trypanocidal activity and active constituents in the seeds of Persea americana Biol Pharm Bull. 2005 Jul;28(7):1314-7.. Abe F, Nagafuji S, Okawa M, Kinjo J, Akahane H, Ogura T, Martinez-Alfaro MA, Reyes-Chilpa R.


Carotenoid absorption from salad and salsa by humans is enhanced by the addition of avocado or avocado oil. Unlu NZ, Bohn T, Clinton SK, Schwartz SJ. J Nutr. 2005 Mar;135(3):431-6.