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Vegetarianism: What the Science Tells UsBy Sally Fallon and Mary G Enig, PhD Health writers may denigrate animal foods with insouciance but, in fact, the scientific literature offers very little in the way of long-term studies on the value of a vegetarian diet. Dr. Russell Smith, a statistician, analyzed the existing studies on vegetariansim1 and discovered that while there have been ample investigations which show, quite unsurprisingly, that vegetarian diets significantly decrease blood cholesterol levels, studies evaluating the effects of vegetarian diets on mortalities continue to be few in number. In fact, Smith speculated that the available data from the many existing prospective studies are being shelved because they reveal no benefits of vegetarianism. For example, mortality statistics are strangely absent from the Tromso Heart Study in Norway which showed that vegetarians had slightly lower blood cholesterol levels than nonvegetarians.2 In a review of some 3,000 articles in the scientific literature, Smith found only two that compared mortality data for vegetarians and nonvegetarians. One was a 1978 study of Seventh Day Adventists (SDAs). Two very poor analyses of the data were published in 1984, one by H. A. Kahn and one by D. A. Snowden.3 The publication by Kahn rather arbitrarily threw out most of the data and considered only subjects who indicated very infrequent or very frequent consumption of the various foods. They then computed "odds ratios" which showed that mortality increased as meat or poultry consumption increased (but not for cheese, eggs, milk or fat attached to meat.) When Smith analyzed total mortality rates from the study as a function of the frequencies of consuming cheese, meat, milk, eggs and fat attached to meat, he found that the total death rate decreased as the frequencies of consuming cheese, eggs, meat and milk increased. He called the Kahn publication "yet another example of negative results which are massaged and misinterpreted to support the politically correct assertions that vegetarians live longer lives." The analysis by Snowden published mortality data for coronary heart disease (CHD), rather than total mortality data, for the 21-year SDA study. Since he did not eliminate the intermediate frequencies of consumption data on meat, but did so with eggs, cheese and milk, this represents further evidence that both Kahn and Snowden based their results on arbitrary, after-the-fact analysis and not on pre-planned analyses contingent on the design of their questionnaire. Snowden computed relative risk ratios and concluded that CHD mortality increased as meat consumption increased. However, the rates of increase were trivial at 0.04 percent and 0.01 percent respectively for males and females. Snowden, like Kahn, also found no relationship between frequency of consumption of eggs, cheese and milk and CHD mortality "risk." Citing the SDA study, other writers have claimed that nonvegetarians have higher all-cause mortality rates than vegetarians4 and that, "There seems little doubt that SDA men at least experience less total heart disease than do others. . ."5 The overpowering motivation to show that a diet low in animal products protects against CHD (and other diseases) is no better exemplified than in the SDA study and its subsequent analysis. While Kahn and Snowden both used the term "substantial" to describe the effects of meat consumption on mortalities, it is more obvious that "trivial" is the appropriate descriptor. It is also interesting that throughout their analyses, they brushed aside their totally negative findings on foods which have much greater quantities of fat, saturated fat and cholesterol. The second study was published by Burr and Sweetnam in 1982.6 It was shown that annual CHD death rate among vegetarians was only 0.01 percent lower than that of nonvegetarians, yet the authors indicated that the difference was "substantial." The table below presents the annual death rates for vegetarians and nonvegetarians which Smith derived from the raw data in the seven-year Burr and Sweetnam study. As can be seen, the "marked" difference between vegetarian and nonvegetarian men in Ischemic Heart Disease (IHD) was only .11 percent. The difference in all-cause death rate was in the opposite direction, a fact that Burr and Sweetnam failed to mention. Moreover, the IHD and all-cause death rates among females were actually slightly greater for heart disease and substantially greater for all causes in vegetarians than in nonvegetarians.
Annual Death Rates of
Vegetarians and Nonvegetarians
These results are absolutely not supportive of the proposition that vegetarianism protects against either heart disease or all-cause mortalities. In fact, they indicate that vegetarianism is more dangerous for women than for men. The claim that vegetarians have lower rates of cancer compared to nonvegetarians has been squarely contradicted by a 1994 study comparing vegetarians with the general population.7 Researchers found that although vegetarian Seventh Day Adventists have the same or slightly lower cancer rates for some sites, for example 91 percent instead of 100 percent for breast cancer, the rates for numerous other cancers are much higher than the general US population standard, especially cancers of the reproductive tract. SDA females had more Hodgkins disease (131 percent), more brain cancer (118 percent), more malignant melanoma (171 percent), more uterine cancer (191 percent), more cervical cancer (180 percent) and more ovarian cancer (129 percent) on average.  Mary
G. Enig, PhD is an expert of international renown in the field of lipid
biochemistry. She has headed a number of studies on the content and effects of
trans fatty acids in America and Israel, and has successfully challenged
government assertions that dietary animal fat causes cancer and heart disease.
Recent scientific and media attention on the possible adverse health effects of
trans fatty acids has brought increased attention to her work. She is
a licensed nutritionist, certified by the Certification Board for Nutrition Specialists,
a qualified expert witness, nutrition consultant to individuals, industry and
state and federal governments, contributing editor to a number of scientific publications,
Fellow of the American College of Nutrition and President of the Maryland Nutritionists
Association. She is the author of over 60 technical papers and presentations,
as well as a popular lecturer. Dr. Enig is currently working on the exploratory
development of an adjunct therapy for AIDS using complete medium chain saturated
fatty acids from whole foods. She is Vice-President of the Weston A Price Foundation
and Scientific Editor of Wise Traditions as well as the author of Know
Your Fats: The Complete Primer for Understanding the Nutrition of Fats, Oils,
and Cholesterol, Bethesda Press, May 2000. She is the mother of three healthy
children brought up on whole foods including butter, cream, eggs and meat.
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Sally
Fallon is the author of