While Dr. Byrnes claims that it is well known that his references will be forthcoming in later articles, it was not something that I knew. Therefore, I was expecting to see more than a few books and a couple of articles supporting his position.
Hundreds of references point to the benefits of a mostly vegetarian diet, and I will not be drawn into the defense of the most rigid diet, or distinctions between a healthy, mostly-vegetarian diet that includes some eggs and low-fat dairy products (or even occasional fish) and his supposedly objectionable vegan diet, when compared to the detrimental effects of the high meat diet advocated by Dr. Byrnes.
While I did not realize that Dr. Byrnes was opposed to taking dietary supplements, it is clear that he ignores their health value, and he misrepresents my position on this. A healthy mostly-vegetarian diet does not absolutely require dietary supplements to achieve basic levels of nutrition, but I recommend them for everyone no matter what their diets, based on the scientific support for their value in higher amounts for prevention and treatment of many diseases.
It is not my position that you have to take them unless you choose to be a strict vegan for reasons other than health, and I have no objection to that choice as long as the person recognizes the potential problems and deals with them - through supplements, if necessary. Nonetheless, several articles do suggest that adequate seaweed in the diet, and perhaps chlorella, can provide B12 for vegans, but I do not suggest relying on that source alone.
I never said that miscarriages are "normal" but that they are not uncommon, and that they are UNRELATED to a vegetarian diet, although they may be related to poor nutrition, even on an high meat diet (especially since this tends to be lower in folic acid than a vegetarian diet).
Dr. Byrnes' solution again is to go on an unhealthy diet to solve a problem that is not related to low meat intake - risk increased cancer, heart disease, accelerated aging, arthritis, diabetes, strokes, hypertension, and other diseases instead of dealing with the source of the problem (sometimes low thyroid, sometimes other health issues).
While homocysteine in some studies is elevated in some vegetarians, this is only a risk factor for heart disease, and not the disease itself. As the literature shows consistently lower heart disease in vegetarians, we have to be careful not to try to treat the lab test at the expense of the patient's health.
Humans are very much like gorillas in terms of metabolism, in spite of Dr. Byrnes' denials. The few larvae that they scratch up for "meat" do not relate to the levels of meat in the diet that Dr. Byrnes is recommending. To say that in captivity they eat more meat is rather meaningless, as when humans are given a selection of processed foods they will also choose them, as well as sugar and salt, as evidenced by the rise of junk in the diet and fast food restaurants.
I assume that captivity is not what Dr. Byrnes calls the natural habitat. When meat and butter were rationed in Denmark during the war, levels of heart disease and overall mortality went down. That people might choose meat when it is available does not mean that it is healthy.
Dr. Byrnes' glib dismissal of the vast weight of medical science by saying that "conclusions drawn from these studies remain controversial" is to ignore the clear risks of not paying attention to the current state of knowledge. He is wrong that science is not based on "majority" rule. No, it is not by vote, but by the weight of the evidence that conclusions are drawn, and this is something like majority rule. We cannot accept that one article disproves the information from hundreds of others.
It is not that exceptions prove the rules, but that because all studies are flawed to some degree, we have to accept the accumulation of evidence over years, and not depend on any one study to draw conclusions. That Dr. Byrnes can dismiss all studies that contradict his position and favor the one or two that he finds to support it is to wear blinders in order to remain undistracted by the truth.
Regarding ancient diets, independent of what people may or may not have done millions of years ago, the current evidence clearly shows that vegetarians have better health status in numerous parameters. In addition, contrary to Dr. Byrnes' claim, vegetarians have a better antioxidant status than meat eaters. Numerous studies support this, and in addition, the data you really want is the result of these differences in lower disease rates, which my references consistently support. Vegetarians have an enhanced natural killer cell activity - double the rate in non-vegetarians, and the authors of this study say that this perhaps explains the lower risk of cancer in vegetarians.
And it is not just one article that shows that vegetarians have better immune status, but numerous articles, and to suggest that this is controversial is only to recognize that no scientific conclusions are ever final, and we still make decisions on the best evidence and the weight of the evidence. Citing individuals who eat only meat for one year, or small groups that eat meat and do well, bears little weight compared to hundreds if not thousands of scientific articles, with both interventional and epidemiological studies, that show that a high meat diet is not as healthy as a vegetarian diet.
Some other studies of the Masai suggest that they do not die of heart disease mainly because of their level of physical activity, but their very large arteries do have significant atherosclerotic plaque (Mann GV, Atherosclerosis in the Masai. Am J Epidemiol 1972 Jan;95(1):26-37). Also, I would need to know the average life expectancy in Eskimos before concluding that their apparent current health on native diets would persist for decades.
They also live very physical lives, and a large part of their animal food is fish. (While they have lower heart disease deaths than the American population in general, they do have more strokes.)
While it is correct that CLA from dairy fat inhibits tumor formation, the studies suggest that it is useful at less than or equal to only one percent of the diet, which fits easily into a low-fat, mostly vegetarian diet with small amounts of dairy product.
Lastly (as there is not time or room to present the entire rebuttal to Dr. Byrnes again, as many of his points are answered in my original piece and in those references), the estrogenic pesticides in meat are far greater than in produce, whole grains, and legumes. I recognize that non-organic vegetarian foods might have some of these, but the hazards are not the same, as Dr. Byrnes states; they are far lower on a vegetarian diet because the pesticides are not as concentrated as they are in animal products.
Myth's 3 and 4
Most of Dr. Byrnes' criticisms are directed at vegan diets, but he appears to lump all forms of vegetarian diets together. I still maintain that a diet with no meat or chicken is clearly a far healthier diet than one with these foods, and a vegan diet can be healthy with some minor adjustments for a few deficiencies. To criticize the entire diet because there may not be enough vitamin B12, even though there may be many other health benefits, is inappropriate.
While vitamin D status may be lower on vegan diets, the typical mostly-vegetarian diet is ample in vitamin D, as vitamin D is present in abundance in egg yolks and fish oils, but while there is very little in meat. Some studies even show that vegetarian women have better vitamin D status during pregnancy than omnivores. In addition, the higher protein content of diets containing meat and chicken increase the risk of bone loss through excessive urinary calcium excretion, and they increase the risk of kidney stone formation.
Vitamin A status is not a problem for vegetarians, even on a vegan diet. Dr. Byrnes is incorrect in his conversion factor of 6:1 for beta-carotene to vitamin A activity. The laboratory ratio is between 2:1 and 4:1, but the National Academy of Science has set the equivalence for dietary purposes at 6:1 to leave a margin of safety. This means that 25,000 IU of beta-carotene would supply about 6000 to 12000 IU of vitamin A activity, and this is simply little more than the amount supplied by two carrots.
As diets high in fruits and vegetables have abundant beta-carotene, the conversion is not generally an issue. Dr. Byrnes is right that sick people (hypothyroid, malnourished people) might not convert as efficiently, but high amounts of carotenoids may make up for that, and the solution is not to put sick people on an unhealthy, high-meat diet, but to treat their illness.
Michael Janson, MD
Michael Janson, M.D., is past-president of both the American College for Advancement in Medicine and the American Preventive Medical Association. He founded one of the first complementary/alternative medical practices in New England in 1976. He has lectured widely on the subjects of nutrition, complementary/alternative medicine, vitamin supplements, and chelation therapy. He has been on a mostly vegetarian diet since 1975.
Dr. Janson is the author of: The Vitamin Revolution in Health Care; Chelation Therapy and Your Health; All About Saw Palmetto and Prostate Health; and Dr. Janson's New Vitamin Revolution (Penguin-Putnam-Avery, 2000). He has written articles for many health magazines and newspapers, and he is a regular radio-show guest. He publishes a monthly newsletter, Dr. Michael Janson's Healthy Living, available free by Email (newsletter@drjanson.com) by placing "text newsletter" in the subject line. His website is www.drjanson.com.
References
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Krajvcovivcova-Kudlavckova M, et al., Nutritional status in adults on an alternative or traditional diet. Cas Lek Cesk 2001 Mar 15;140(5):142-6.
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Grant WB, An ecologic study of dietary and solar ultraviolet-B links to breast carcinoma mortality rates. Cancer 2002 Jan 2;94(1):272-81
Bairati I, et al., Dietary fat and advanced prostate cancer. J Urol 1998 Apr;159(4):1271-5.
Nutritional Biochemistry and Metabolism, ed M.Linder, Elsevier Medical Press
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