CAUTION! Consume Soy at Your Own Risk


Do you believe that soy is a beneficial health food? Many women believe soy foods can control menopausal symptoms. Research hasn’t proven that soy does anything for hot flashes or other menopausal symptoms among other health issues.

The vast majority of soy at your local market is not a health food. The exception is fermented soy which will be explained later. Even worse GMO soy that is contaminated with large pesticide residues. GMO soy is sprayed with the potent toxic herbicide Roundup to improve crop production by killing the weeds.


Soybeans have long been recognized as a plant food high in protein. Yet it is typically lower in certain amino acids (which are the building blocks that help our bodies repair among other factors). Once adjustments have been made for digestibility and other metabolic factors, soybeans turn out to receive a protein quality rating that is equal to the ratings for eggs or cow’s milk. The peptides in soy are known as defensins, glycinins, conglycinins and lunasin, and all have definite health improving benefits, such as blood pressure regulation, better blood sugar control and improved immune function.

Many studies that are done on soy protein are on risks of coronary heart disease (CHD). Found that approximately 30 grams of soy protein were consumed on a daily basis which lowered LDL cholesterol. But studies like this may have been on whole soybeans versus processed.

No phytonutrient in soy has received more widespread attention than genistein. This is an isoflavone that has been studied extensively in relationship to its cancer risk. Isoflavones are a form of plant-based estrogen.  Soy isoflavones are unlikely to have enough estrogenic activity to have an important impact on hot flashes and other symptoms of menopause.

All of the cancer preventing possibilities of genistein and soy are complicated by other real-life factors. In some studies, the amount of genistein required to trigger cancer preventing effects has been relatively high, and far higher than the amount provided by average intake among U.S. adults. The life cycle and metabolic states of individuals also seems to make a potentially important difference in the anticancer benefits of soy.

Soybeans can block graphicproduction of thyroid hormones. Soy is considered to be an anti-thyroid agent, working against the thyroid by inhibiting thyroid peroxidase (TPO) which disturbs proper thyroid function. Low thyroid activity effect women in American, particularly middle-aged women. Thyroid runs our metabolism.
When thyroid production is low, energy levels as well as body heat are also low. Low thyroid means the action of the heart is also reduced, resulting in lack of oxygen to the cells, a prime condition for cancer. Low thyroid function also makes weight loss very difficult to achieve.


Soy has long been a topic in thyroid dysfunction. Thyroid enlargement, in both iodine deficient rodents and infants fed soy-flour based formulas without iodine fortification.  Infants with congenital hypothyroidism who consume soy formulas require approximately 25% more synthetic hormone than those on soy-free formula. In an article reported in the Huffington Post it says, “infants fed soy formula take in an estimated five birth control pills worth of estrogen every day.” This is probably due to the goitrogens in soy that can interfere with the utilization of iodine or functioning of the thyroid gland and cause thyroid problems. However, it appears that consumption of soy could cause goiter growth only in animals or humans consuming diets marginally adequate in iodine or who were predisposed to develop goiter development. In most cases dietary supplementation with adequate iodine can reverse the disorders. Blood levels of iodine can be tested with a blood test.

Other problems with soy may be in the digestion and the type of soy that is being consumed (processed versus whole). Asian versus non-Asian populations digest soybeans in such a way as to convert daidzein (one of soy’s key isoflavone phytonutrients) into equol (a closely-related phyto nutrient considered to be an isoflavone). By contrast when adults in the U.S. eat soybeans, only 25 – 30% metabolize daidzein in this way. The role of bacteria in the digestive tract seems critical in the equol production process. A soy-related dietary practice that works for adults in China may not work for adults in the U.S.

 Sliced Tempeh

Sliced Tempeh

For centuries Asian people have been consuming fermented soy products such as natto, tempeh, and soy sauce.Fermented soy does not wreak havoc on your body like unfermented soy products do. Fermented soy is a great source of vitamin K2 (combined with vitamin D) is essential in preventing osteoporosis, cardiovascular disease, dementia, and various types of cancer.

For example, in studies on soy intake and breast cancer, women who are pre-menopausal and develop tumors that are neither estrogen receptor nor progesterone receptor positive, soy and genistein intake do not appear to offer risk reduction. Avoiding the development of various cancers involves many factors. We need large amounts of fruits and vegetable, not just soy.  Many other foods provide benefits that far outweigh the intake of soy.  If you need to have soy in your dietary plan, consult with your health care provider, qualified nutritionist or a naturopathic specialist.




Chao Wu Xiao. Health Effects of Soy Protein and Isoflavones in Humans. The Journal of Nutrition. Evidence for Health Claims on Food: How Much is Enough?


The George Matelijan Foundation. Soybeans.


The George Matelijan Foundation. Can you tell me abuot the goitrogenic substances in food?


The George Matelijan Foundation. Why is there so much controversy about soybeans?  Soy: This “Miracle Health Food” Has Been Linked to Brain Damage and Breast Cancer.  September 18, 2010. Got Thyroid Problems? Then Stop Consuming Soy.

October 13, 2010.


HuffPost Healthy Living.  The Health Dangers of Soy.


Barbara L. Minton. Fermented Soy is Only Soy Food Fit for Human Consumption.