Insights on Soy: An Open Letter to Ocean and John Robbins

Insights On Soy

Dear Ocean,

Thank you to both you and John for the heroic work you are doing in campaigning for veganism. As a holistic physician and successful vegan for more than 35 years, I feel completely aligned with your support of a plant-based diet. I’m writing this letter in response to John Robbins’ soy article (recently reprinted in 2013 in your newsletter as the most comprehensive article on soy). At one point in the ’60’s and ’70’s, when my personal community was literally making our own soy products for personal consumption, soy was seen as the great protein substitute for vegetarians and vegans, but that is no longer the case. The Price Foundation’s attack on soy could clearly be seen as an attempted attack on the vegan/vegetarian lifestyle under the guise of “science”, but that clearly is not my agenda. A close reading of the book Nutrition and Physical Degeneration by Weston Price does not even emphasize the lack of meat as a problem, but rather the introduction of white flour, white sugar, and junk foods as the primary degenerative force in the diet. It may be more productive to explore how to optimize and make people successful on a vegan diet rather than focus on these people and their narrow anti-soy, anti-vegan, pro-meat position.

One key to this discussion is that soy is no longer needed in the diet to be a successful vegan so defending soy does not need to be linked to promoting veganism. I am 1,000% committed to having people be successful on a vegan diet. My success rate is 99.99%, having only had one person in my 40 years be unsuccessful with veganism. (She happened to have been born near the Arctic Circle, and needed to eat fish one time per week to make it work for her.) When one understands the science of individualizing the diet there is no need for vegans to ever need to eat fish, as some of the leaders in the vegan movement have publicly admitted they are now doing. One of the things that I teach based on human studies (I agree with John that animal studies are not as accurate), is that there may be some dangers associated with eating soy. I would like to highlight those studies to emphasize why I do not recommend soy other than as a transition food for new people moving into a vegetarian/vegan lifestyle and only fermented soy if at all. Part of this 99.99% success is that I see veganism through the eyes of a holistic approach, which enhances every quality of one’s life and does not hang onto the past.

One current major problem with soy is that 92-94% of soy is genetically modified.i The issue with soy being genetically modified goes further into specifics. GM soy is loaded with toxic pesticides. Keep in mind that although 6-8% of soy is organic, I question in the complex ecological picture of cross-pollination, how “organic” is this 6-8%? Genetically modified plants contain genes from bacteria that produce a protein that has never been part of the human food supply. We do not even begin to know the implications of this. The only published human feeding study on GM foods ever conducted did verify that the gene inserted into GM soy transfers into the DNA of our gut bacteria.ii This means that we actually may be producing this allergenic protein in our gut with those bacteria. The GM soy has been linked to an increase in allergies, which has important ramifications such as soy has now become one of the top seven allergens. Also important is that the GM soy has a lot more of these toxic pesticides than humans can safely tolerate. That toxic herbicide is called Roundup Ready. In my book Rainbow Green Live Food Cuisine, I cite that by the 1990’s, glyphosate was listed as the most common cause of all of forms of pesticide–related illness in California and with an increased risk of non-Hodgkin’s’ lymphoma which is considered the third fastest growing cancer in the U.S.iii

There are also a variety of debated soy issues that may be inconsequential: such as soy containing anti-nutrients, such as saponins, soyatoxin, phytates, protease inhibitors, oxalates, goitrogens, and estrogens. Counter claims are that vegans have not been shown to be mineral deficient. It is interesting to note that in Senate Document No. 264, 1936, US Congress declared that 99% of Americans were mineral deficient. Almost everyone I see, meat eaters or vegans are mineral deficient. However, this cannot in any reasonable way be blamed on soy. Soy also contains hemagglutinins, which theoretically would make one’s blood thicker. This has never been clinically proven in those who eat soy. Soy does have toxic levels of aluminum and manganese connected to soy production procedures.iv Soy formula has up to 80 times more manganese than what we find in breast milk. These are all areas of controversy that seem to be more theoretical points than having clinical ramifications.

Does soy prevent or cause cancer is another debatable issue? The Japanese who ingest up to 30 times more iodine than North Americans, which helps to protect the reproductive organs and especially the breasts from cancer, have a lower incidence of breast, uterine, and prostate cancer. It is rarely mentioned that while this is statistically true, the Japanese and other Asian soy eaters, also have higher rates of other types of cancers including cancer of the esophagus, stomach, pancreas, and liver, but lower rates of thyroid cancer. The cancer topic has been debated back and forth and remains a debate that will be resolved in time as the research unfolds, but it is something to consider in the overall discussion.  I would only add to the discussion consideration that progesterone has a general anticancer apoptosis effect (the ability to kill cancer cells), and estrogen dominance generally is linked with cancer cell production.

One area of concern that seems to be reasonably well documented is: “The amount of phyto-estrogens that are in a day’s worth of soy infant formula equals 5 birth control pills,” says Mike Fitzpatrick, a New Zealand toxicologist.v Another study reported in The Lancet found that the “daily exposure of infants to isoflavones in soy infant-formulas is 6–11-fold higher on a bodyweight basis than the dose that has hormonal effects in adults consuming soy foods.”vi This estrogen dose referred to in the research as equivalent to what comes from two glasses of soymilk per day was enough to change menstrual patterns in women.vii In the blood of infants tested in this study, who were on soymilk as a substitute for mother’s milk, concentrations of isoflavones were 13,000 to 22,000 times higher than natural estrogen concentrations in early life. Whether one bottle of soymilk has the equivalent of one or five birth control pills, there are other implications from this that may not be too healthy. At some point it will become clear that high estrogen is not good for male or female fetuses or children, particularly in the areas of sexual development and reproductive health.

In 2003, a study was done comparing the bodily IGF-1 increase promoted by 40 grams of soy (the amount in one soy candy bar and a soy shake, or four soy patties) versus 40 grams of milk protein. Soy was found to be almost twice as powerful as milk protein in increasing IGF-1 levels (36 percent for milk, 69 percent for soy).viii This new IGF-1 data potentially places soy in the category of a powerful cancer promoter of the breast, prostate, lung, and colon.ix Although it is controversial, there are many in the medical world that feel that excessive IGF-1 could stimulate the aforementioned cancers if they are already present. This is why Canada does not allow rBGH milk from the U.S. because it is so much higher in IGF-1. In essence, this is still at the level of theoretical speculation but it merits a preventive attention.

Once we move past the debatable aspects of the soy discussion it will be useful to look at the less debatable aspects of my concern. One, as already referred to, is its allergenic aspects. In 1986, Stuart Berger, MD, placed soy among the seven top allergens—one of the “sinister seven.”x  Scientists are not completely certain which components of soy cause allergic reactions. They have found at least sixteen allergenic protein components in soy, and some researchers pinpoint as many as thirty.xi Allergic reactions occur not only when soy is eaten but also when soybean flour or dust is inhaled.

Another undebatable fact is that all cooked soy naturally produces MSG. All soy products, except edamame, are processed. Some such as textured soy protein may actually have even more MSG added to them. This is a real concern. It matters not whether the soy is organic or GMO. If it is cooked it produces MSG. This is not a theoretical speculation. MSG has been conclusively linked with brain damage, endocrine disorders (particularly disruption of the hypothalamic function), reproductive disorders, behavior disorders, general adverse reactions, and neuro-degenerative diseases. This is not something that I particularly recommend exposing yourself to. In essence, all soy ingestion except edamame, whether GMO or not, then exposes you to MSG.

Following and perhaps associated with this MSG fact is what I consider, the most important thing about the soy question which is its effect on the brain.  There is some suggestion that soy may be connected with 2.4 higher rate of Alzheimer’s disease and also accelerated brain degeneration. As I point out in my new edition of There Is A Cure for Diabetes, soy is considered kaphagenic in the 3,000-year old Ayurvedic system of medicine, which means it is associated with increasing the incidence of diabetes and the incidence of diabetes with heavy soy users seems to be 200% more.

In a major ongoing study involving 3,734 elderly Japanese American men, those who ate the most tofu during midlife had up to 2.4 times increased risk of later developing Alzheimer’s disease. As part of a three-decade-long Honolulu-Asia Aging Study, twenty-seven foods and drinks were correlated with participants’ health. Men who consumed tofu at least twice weekly had more cognitive impairment than those who rarely or never ate the soybean curd.,xiixiii Going further, higher midlife tofu consumption was also associated with low brain weight suggesting soy consumption is associated with brain cell destruction and loss. Brain atrophy was assessed in 574 men using MRI results and in 290 men using autopsy information. Shrinkage occurs naturally with age, but for the men who had consumed more tofu, lead researcher, Dr. Lon R. White from the Hawaii Center for Health Research,  said, “Their brains seemed to be showing an exaggeration of the usual patterns we see in aging.” This level of epidemiology and hard science combined is a significant consideration in the soy discussion.

This all fits together with a pattern of soy affecting the brain, including the MSG exposure, the allergies causing brain inflammation (a driving force behind Alzheimer’s) and accelerated brain aging. The association with overall brain shrinkage and brain cell destruction and loss makes me more than uncomfortable to recommend soy.

There are two other points that need to be addressed:

John Robbins said that very few people have iodine deficiencies in the U.S. That is simply an incorrect statement. One major study from 1997 to 2005 done in the U.S. with 4,000 people showed that of 96% of the American populace is deficient in iodine. Seventy two to seventy-four percent of the global population is also deficient in iodine. I also want to point out, contrary to John Robbins’ suggestion that salt is iodized, that only about 20% of salt today is iodized anymore. Even if iodized salt is ingested, it only has about 10% bioavailablity, with it being both chlorinated and having toxic stabilizers and excipients. This is because iodized salt is not mandated in restaurant or processed foods; and sea salt is only 1/71 the iodine amount that in iodized salt. Another problem is that soy, and particularly soy oil, are both major stealers of iodine from the system. Low iodine is a contributor to hypothyroidism, cretinism and diminishing many body functions. Soy has been noted to have other goitrogenic factors which contributes to hypothyroidism. Though the hypothyroid issue appears to be debatable, a major syndrome I see in nearly all my patients, whether or not they are eating soy, are vegan, or are eating live foods, or meat is low thyroid function. Nearly everyone I see clinically is deficient in iodine and is suffering from subclinical symptoms of iodine deficiency, which certainly correlates with the seven-year study showing 96% deficiency in Americans. Avoiding soy helps to minimize this low thyroid problem. I would also like to point out that the people in Japan, before Fukushima, had less thyroid trouble probably related to a 30 times higher iodine intake. However, with the recent Fukushima disaster and its continued radiation spills there is increased thyroid disease happening in Japan and worldwide. More disturbing is a recent study found that children born in Alaska, California, Hawaii, Oregon, and Washington between one week and sixteen weeks after the Fukushima meltdown were 28% more likely to suffer from congenital hypothyroidism than those children born in those same states during the same period one year earlier. Congenital hypothyroidism in this case clearly came from a buildup of radioactive I-131 in the thyroid. If a baby has adequate iodine in the thyroid, the I-131 cannot get in. So adequate iodine is a key protector against I-131 toxicity. Given that the toxic radiation from Fukushima is actually increasing it makes reasonable sense to minimize anything that would decrease iodine saturation in the body, such as soy, and add as much iodine to increase iodine saturation as a protection against absorbing I-131.

When we refer to the longevity of Okinawans pre-Fukushima, and attribute it to their soy intake  (others contribute their longevity to their intake of coral calcium) we are not considering the cultural and genetic influences on their longevity. It is superficial to correlate their longevity with soy, and, of course, most Americans are not Okinawans. This is a speculative theory and potentially misleading. We have to be careful making cross-cultural comparisons.

Another issue that has come up is the concern about men eating soy is that soy isoflavones have been show to reduce testicular function and lower the luteinizing hormone (LH) with signals the testicles to work. A high soy intake and potentially lower level of LH increases the probability of estrogen dominance in men, contributing to hair loss, swollen and cancerous prostates, and insulin resistance.,xivxv Dorris Rapp, MD, a leading pediatric allergist, asserts that environmental and food estrogens are responsible for the worldwide reduction in male fertility. Soy intake has been associated with a decrease in sperm fertility. Recent human research has shown that soy intake is associated with 50% decrease in sperm fertility.xvi This kind of research on humans is very hard to ignore, when we speak of survival of the species.

In concluding this discussion, soy was, at one point in the 1960’s, considered an important vegan protein source as soy is 38% protein and 25% carbohydrate. Obviously several changes have happened since the 60’s. The most serious detrimental change has been the introduction of GM soy. Another positive consideration is that many other high quality proteins are available with better assimilation and higher protein percentage. For example, spirulina, chlorella, and Klamath Lake blue green algae have 60-70% protein (at least 1/3 higher than soy) and are 95% assimilable in humans. We also have other high quality, natural, unprocessed raw proteins concentrates available such as pumpkin seed protein concentrates. The star role that soy once played has, in essence, become obsolete. I agree with John Robbins when he says that, “the health benefits of soy may be negated by the dangers of GMO soy”. That certainly is a major consideration in this discussion. The other major consideration is the human data associated with various levels of accelerated brain cell degeneration in soy eaters. A third major concern, though less clinically proven, is the significantly increased estrogen associated with soy consumption, especially in babies. What we once considered a great food and protein is not the same soy that is generally available today. There is a Biblical teaching regarding food selection that makes the point of this soy discussion extremely clear: If there is a chance of harm with a food, don’t eat it. This is especially true if better options are available.

While in the last forty years soy has occupied an important place in the transition from an unhealthy meat-based diet to vegetarian and vegan cuisine, it may be time for us to upgrade our food choice to one having more benefits, and fewer negative possibilities. Eliminating soy from your diet can be tough if you are just eating processed vegetarian or vegan food. Many pre-packaged and prepared foods contain soy as an ingredient, but it may be listed as “textured vegetable protein” (TVP), “textured plant protein,” or  “hydrolyzed vegetable protein” (HVP). They all have naturally occurring MSG (monosodium glutamate) and often have MSG additionally added as well. The recipe section of my second edition of there is a Cure for Diabetes book will provide you with ample foods that are nutrient-dense, non-allergenic, delicious, and filling, and that will have you wondering why you ever ate processed soy-containing meals.

May all be blessed to look clearly at what is best for optimal health and see the changes occurring in today’s food supply, and make the adjustments that can help us be optimally healthy and vibrant vegans living in enduring radiant health.


Rabbi Gabriel Cousens, M.D., M.D.(H.), N.D.(h.c.), D.D., Dip. Ayurveda, Dip. American Board of Holistic Medicine, Director and Founder of Tree of Life Center US and Tree of Life Foundation


i  Found at:

ii Found at:

iii Cousens, Gabriel. Rainbow Green Live Food Cuisine. North Atlantic Books, Berkley, CA. 2003. pp 92

iv Found at:

“Soy infant formula could be harmful to infants: Groups want it pulled.” Nutrition Week,December 10, 1999, 29(46).

vi Setchell, Zimmer-Nechemias, Cai, et al. “Exposure of infants to phytoestrogens.”

vii Cassidy, A, Bingham, S, and Setchell, K D. “Biological effects of a diet of soy protein rich in isoflavones on the menstrual cycle of premenopausal women.” Am J Clin Nutr, September 1994,60(3): 333–40.

viii Arjmandi, B H, Khalil, D A, Smith, B J, Lucas, E A, Juma, S, Payton, M E, and Wild, R A. “Soy protein has a greater effect on bone in postmenopausal women not on hormone replacement therapy, as evidenced by reducing bone resorption and urinary calcium excretion.”J Clin Endocrinol Metab, March 2003, 88(3): 1048–54.

ix Yu, H. “Role of the insulin-like growth factor family in cancer development and progression.“ J Natl Cancer Inst, September 20, 2000, 92(18): 1472–89.

x Berger, S. Dr. Berger’s Immune Power Diet. New York: New American Library, 1986.

xi Daniel, K T. The Whole Soy Story.

xii White, L R, Petrovich, H, Ross, G W, and Masaki, K H. “Association of mid-life consumption of tofu with late life cognitive impairment and dementia: The Honolulu-Asia Aging Study.” Presented at the Fifth International Conference on Alzheimer’s Disease, July 27, 1996 (Osaka,Japan).

xiii White, L R, Petrovitch, H, Ross, G W, Masaki, K H, Hardman. J, Nelson. J, Davis. D, and Markesbery, W. “Brain aging and midlife tofu consumption.” J Am Coll Nutr, April 2000, 19(2): 242–55.

xiv Nagata, C, et al. “Inverse association of soy product intake with serum androgen and estrogen in Japanese men.” Nutr Cancer, 2000, 36(1): 14–18.

xv Zhong, Ying, et al. “Effects of dietary supplement of soy protein isolate and low fat diet on prostate cancer.” FASEB J, 2000, 14(4): a531.11.

xvi Rapp, D J. Is This Your Child’s World? New York: Bantam Books, 1996, p. 501.