Categories: Nutrition, Soy

Soy: Miracle Food?​

Compiled by: Health Action Network Society

What has science been telling us? What does history reveal?

“Current evidence for the beneficial effects of soy requires a full understanding of potential adverse effects as well.”
Dr D Doerge, scientist from the National Center for Toxicological Research.

Quoted here are many of the scientific research studies on soy spanning the years 1925 through 2001.

Soy Blocks Vitamin and Mineral Absorption: Studies indicate that soy (organic and non-organic) causes increased requirements for vitamins E, K, D and B12. Phytic acid from SPI (soy protein isolate) blocks the absorption of essential minerals and creates deficiency symptoms of calcium, magnesium, copper, molybdenum, iron, manganese and especially zinc in the intestinal tract. (2) This may be contributing to the early onset of osteoporosis in Japan, starting there as early as age 20 versus age 34 in the USA. (1b) Also test animals fed SPI developed enlarged organs, particularly the thyroid gland and pancreas, and caused increased deposition of fatty acids in the liver.

Soybeans have one of the highest phytate levels of any grain or legume. Phytates in soy are highly resistant to normal phytate-reducing techniques such as long, slow cooking. Only long periods of fermentation will greatly reduce soy’s phytate levels, but will not eliminate them. Soy has natural toxins or anti-nutrients. Soybeans contain potent enzyme inhibitors that block the action of trypsin and other enzymes needed for protein digestion. These inhibitors are not completely deactivated during ordinary cooking. They can produce serious gastric distress, reduced protein digestion and create chronic deficiencies in amino acid uptakes. In test animals, diets high in trypsin inhibitors also caused enlargement and pathological conditions of the pancreas, including cancer. (4,5)

Soy contains haemaglutinin, which is a clot-promoting substance that causes red blood cells to clump together, setting the stage for clogged arteries and stroke. Endocrine-disrupting isoflavones, genistein and daidzein are goitrogenic components found in soy. In vitro studies suggest isoflavones inhibit synthesis of estradiol and other steroid hormones. Infertility, reproductive problems, thyroid and liver disease due to dietary intake of isoflavones have been observed for several species of animals including mice, cheetah, quail, pigs, rats, sturgeon and sheep. (5) 100 grams of soy protein – the maximum suggested cholesterol lowering dose – can contain almost 600mg of isoflavones, an undeniably toxic amount.

Only 45 mg of isoflavones taken daily for one month, in premenopausal women, reduced hormones needed for adequate thyroid function. In some of the women, these effects lingered for 3 months after soy consumption was discontinued. The Swiss Health Service, in 1992, estimated that 100 grams of soy protein provides the estrogenic equivalent of one birth control pill. Processing of soy adds even more toxins. Much soy is acid washed in aluminum tanks, leaching high levels of aluminum into the final product. Nitrites, potent carcinogens, are formed during spray-drying, and toxic lysinoalanine is formed during alkaline processing. Artificial flavorings, particularly MSG are added to SPI and textured vegetable protein (TVP) products to mask their strong, “beany” taste and to impart the flavor of meat. (9)

Cancer and DNA damage

Thousands of women are now consuming soy in the belief that it protects them against breast cancer. Yet in 1996, researchers found that women consuming soy protein isolate (SPI) had an increased incidence of epithelial hyperplasia, a condition that preceded malignancies. Additionally, genistein was found to stimulate breast cells to enter the breast cancer cycle. (5,7,8) Since 1993, soy has been known to cause DNA damage, chromosome fragmentation and errors in chromosome orientation. (5,3) (4) Soy products may increase breast cancer in pregnant women.(3) Soy advertisers collectively claim lower rates of reproductive cancers for Japanese and Asians eating soy, while ignoring the fact that these people also have much higher rates of cancer of the esophagus, stomach, liver, pancreas and thyroid, particularly as soy causes these same types of cancer in laboratory rats.

Brain – Aging and learning disabilities

Japanese Americans living in Hawaii show a significant statistical relationship between two or more servings of tofu a week and accelerated brain aging (atrophy). Participants in another study who ate tofu in mid-life had lower cognitive function in later life, experienced greater incidence of Alzheimer’s disease and dementia and looked older. There is strong evidence linking brain damage to infants using soy formulas. (3) (5)

Soy infant formula

Daily exposure of infants to isoflavones in soy infant formula is 6 to 11 times higher on body-weight basis than the dose that has negative hormonal side effects in adults consuming soy foods. Approximately 25 per cent of bottle-fed children in the US receive soy-based formula – a much higher per cent than in other parts of the Western world. Toxicologist Dr Mike Fitzpatrick estimated that infants exclusively fed soy formula receive the estrogenic equivalent (based on body weight) of at least 5 birth controls pills per day. By contrast, almost no phytoestrogens have been detected in dairy-based infant formula or in human milk, even when the mother consumes soy products.

In the 1986 Puerto Rico Premature Thelarche Study, the most significant dietary association with premature sexual development was not chicken, as the press reported, but soy infant formula. Early maturation in girls is frequently an indicator of problems with their reproductive system in later life, including failure to menstruate, infertility, breast cancer and possibly uterine cancer. (8) Problems in both sexes associated with soy-based infant formula later in life also include extreme emotional behavior, immune system problems, pituitary insufficiency, irritable bowel syndrome, asthma, thyroid disorders including thyroid problems in babies and infantile leukemia.

Thyroid problems

Asians throughout the world have high rates of thyroid cancer. Japanese researchers reported in 1991 that consumption of as little as 30 grams or 2 tablespoons of soybeans per day for only one month resulted in significant decrease in thyroid-stimulating hormone. Diffuse goiter and hypothyroidism appeared in some of the subjects and many complained of fatigue, lethargy and constipation, even though their intake of iodine was adequate. (5) Soy warning labels, for medical reasons: The USA’s FDA ignored two of their own expert research scientists, Daniel Sheehan, PhD and Daniel Doerge, PhD, who expressed serious concerns regarding the perceived safe use of soy, if soy was to be granted a ‘health claim’.

In their letter of protest they said, “it is inappropriate to allow a health claim for SPI… it could be misinterpreted.. the health labeling of SPI for foods need to be considered just as would the addition of any ‘estrogen’ or ‘goitrogen’ to foods, which are bad ideas. Estrogenic and goitrogenic drugs are regulated by the FDA, and are taken under a physician’s care. Patients are informed of risks, and are monitored by their physicians for evidence of toxicity. No similar safeguards are in place for foods, so the public will be put at potential risk from soy isoflavones in SPI without adequate warning and information.”

Soy protein has not been given GRAS (Generally Recognized as Safe) status because of its carcinogenic properties; neither has it been given pre-market (1a,5) approval for its use in food. It is reasonable to ask – is it even legal to add to our food? (4) ‘Toxic Load’ means that the risk is a function of dose length, dose strength, and of the physical condition of the consumer. Reference: “The Dose Makes the Poison: A Plain-Language Guide to Toxicology,” 2nd edition, by M. Alice Ottoboni.

1a from The Weston A. Price Foundation. Also see update (1b). Both are c 2000 by S. Fallon & M.G. Enig, PhD:
(1a) “Newest Research on Why You Should Avoid Soy” and
(1B) “Tragedy and Hype: The Third International Soy Symposium,”

(2) The Gerson Institute, 1572 Second Avenue, San Diego, California 92101, Phone; 619 685 5353

(3) Optimal Wellness Center, by Dr. Joseph Mercola, and newsletter “eHealthy News you Can Use” (In ‘search’, type: soy)

(4) The 1958 “Delaney Amendment” to the USA FDA Reg.s prohibits the use of any food additive if it is found to cause cancer in any animal species or man, at any dose level. Delayney Clause

(5) Soy OnLine Service, SOS, are a small group of private citizens from New Zealand, the United States and the United Kingdom. They have no industry connections and are not funded by any outside interest groups. Their mission is to uncover truths about soy and to provide consumers with an alternative opinion to the information generated from the soy industry.

(6) USA Scientists Protest Soy Approval, FDA Lay Out Concerns. Researchers, Daniel Doerge PhD and Daniel Sheehan PhD are two of the USA’s Food and Drug Administration ‘s experts on soy who signed a Feb 18 1999 letter of protest documenting 26 referenced studies that show a link between eating soy and serious health problems.

(7) Estrogen found in soy stimulates human breast-cancer cells in mice . Three studies from the University of Illinois, Nov 1, 2001, Abstract EurekAlert Medical Archives.

(8) Basing infant formula on soy? American Association for Cancer Research, article “Uterine Adenocarcinoma in Mice Treated Neonatally with Genistein” June 1, 2001. Abstract, Cancer Research, 61:4325-4328.

(9) The Doctor Within, The Magic Bean? Soy-Taintly Not! Soybean-Bad.

Further details available from Health Action Network Society. A comprehensive information package on soy is available from The Health Action Network Society.

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Author: Research Article