The endocrine disruptors in soy.

You've probably heard quite a bit about phytoestrogens.  The plant compounds that mimic estrogen are touted by some as miracle agents that will prevent cancer, coronary heart disease and osteoporosis (just to name a few).

But there is a much darker side to these compounds which are phyto-endocrine disruptors by any other name.  You'll be shocked to learn that these compounds may actually increase the risk of breast cancer and cause thyroid disease, and angry to discover that soy formulas manufacturers refuse to remove them from their products despite knowing that babies fed soy-formulas risk irreversible damage.

And for a touch of the bizarre how about:

  • Archer Daniels Midland (ADM) Company informing the FDA that they had found that soy phytoestrogens were generally recognised as safe (GRAS).

or how about:

  • Protein Technologies International (PTI) determining that the soy phytoestrogens reduced the risk of coronary heart disease.  The PTI petition was so bad it was even contradicted by the American Soybean Association (ASA).

Follow these links for information on the following topics:

Safety and Benefits of Phytoestrogens in Food - translated from a release from the French Food Safety Agency and the French Health Product Safety Agency.

CANCER patients are being warned to avoid foods rich in soy because they can accelerate the growth of tumours.
The Cancer Council NSW will issue guidelines in January 2007, warning about the dangers of high-soy diets and soy supplements for cancer patients and those people in remission from cancer. "The Cancer Council does not support the use of health claims on food labels that suggest soy foods or phyto-oestrogens protect against the development of cancer.'' Read the article here!

Phytoestrogens and the risk of cancer - They can promote Cancer - Do phytoestrogens prevent cancer??  The evidence to support the industry claim is scant and recent work indicates that phytoestrogens may actually increase the risk of breast cancer.  And HOT OFF THE PRESS are two articles that propose a link between bioflavonoids and soy and infantile leukemia.

Phytoestrogens in the Environment - Hormonally active agents in the environment.

Phytoestrogens and the thyroid. - We're sick of hearing that there are no harmful effects of  phytoestrogens.  However, like many endocrine disruptors, phytoestrogens disrupt thyroid function.  The damage can be permanent but obviously the soy industry think that goitre and hypothyroidism doesn't qualify as evidence of harm!

Phytoestrogens and Male Health - Phytoestrogens can affect male animals health and fertility, what about people?

Phytoestrogens and your baby. - Don't doubt it - phytoestrogens are bad for your baby.   If you are feeding your infant a soy formula our advice is STOP immediately.   Why? Soy formula fed infants receive the same daily dose of phytoestrogens that has been shown to be biologically active in adults!  By exposing your baby to such large amounts of phytoestrogens you are risking permanent endocrine system damage to your child.   There are alternatives to soy formulas that are both lactose and dairy protein free; use one of those instead of soy.  But don't just take our word for it, read for yourself the work of FDA's Dr Dan Sheehan, sex-hormone and thyroid expert Professor Cliff Irvine and phytoestrogen researcher Professor Kenneth Setchell.

If you have fed your child a soy formula and have evidence that they have developed thyroid or developmental disorders we invite to contact us.

Phytoestrogens and infertility. - Phytoestrogens can make animals infertile, what about people?  There is clear potential for phytoestrogens to reduce male fertility.   And If you are a woman trying to conceive our advice is AVOID soy.

Phytoestrogens and Your Pets - Yes, soy can also affect your pets health too!

Phytoestrogens and cognitive function. - Do phytoestrogens rot the brain?

Archer Daniels Midland's GRAS application for soy phytoestrogens. - It's almost too weird to contemplate, but food giant ADM applied to the FDA for Generally Recognised as Safe (GRAS) status to be granted to compounds that are known reproductive toxins!  Read for yourself ADM's bizarre determination that soy phytoestrogens exhibit no adverse affects in humans or animals!   Read also the counter submissions that led to ADM withdrawing their application.

Protein Technologies International's Health Claim petition. - For more soy industry deceit, read excerpts of PTI's Health Claim petition for yourself and how PTI have petitioned the FDA to approve labelling that will promote the consumption of between 25 and 100g per day of soy protein as lowering the risk of coronary heart disease.  But, oops, PTI forgot to mention that such an amount of soy protein could easily result in a megadoses of phytoestrogens; up to 600mg per day!

Soy Dangers Summarised


  • High levels of phytic acid in soy reduce assimilation of calcium, magnesium, copper, iron and zinc. Phytic acid in soy is not neutralized by ordinary preparation methods such as soaking, sprouting and long, slow cooking. High phytate diets have caused growth problems in children.

  • Trypsin inhibitors in soy interfere with protein digestion and may cause pancreatic orders. In test animals soy containing trypsin inhibitors caused stunted growth.

  • Soy phytoestrogens disrupt endocrine function and have the potential to cause infertility and to promote breast cancer in adult women.

  • Soy phytoestrogens are potent antithyroid agents that cause hypothyroidism and may cause thyroid cancer. In infants, consumption of soy formula has been linked to autoimmune thyroid disease.

  • Vitamin B12 analogs in soy are not absorbed and actually increase the body’s requirement for B12.

  • Soy foods increase the body’s requirement for vitamin D.

  • Fragile proteins are denatured during high temperature processing to make soy protein isolate and textured vegetable protein.

  • Processing of soy protein results in the formation of toxic lysinoalanine and highly carcinogenic nitrosamines.

  • Free glutamic acid or MSG, a potent neurotoxin, is formed during soy food processing and added to many soy foods.

  • Soy foods contain high levels of aluminum which is toxic to the nervous system and the kidneys.


  • Babies fed soy-based formula have 13,000 to 22,000 times more estrogen compounds in their blood than babies fed milk-based formula.

  • Infants exclusively fed soy formula receive the estrogenic equivalent of at least five birth control pills per day.

  • Male infants undergo a “testosterone surge” during the first few months of life, when testosterone levels may be as high as those of an adult male. During this period, baby boys are programmed to express male characteristics after puberty, not only in the development of their sexual organs and other masculine physical traits, but also in setting patterns in the brain characteristic of male behavior.

  • Pediatricians are noticing greater numbers of boys whose physical maturation is delayed, or does not occur at all, including lack of development of the sexual organs. Learning disabilities, especially in male children, have reached epidemic proportions.

  • Soy infant feeding—which floods the bloodstream with female hormones that inhibit testosterone—cannot be ignored as a possible cause for these tragic developments. In animals, soy feeding indicates that phytoestrogens in soy are powerful endocrine disrupters.

  • Almost 15 percent of white girls and 50 percent of African-American girls show signs of puberty such as breast development and pubic hair, before the age of eight. Some girls are showing sexual development before the age of three. Premature development of girls has been linked to the use of soy formula and exposure to environmental estrogens such as PCBs and DDE.