By Candace McNaughton, ND
There is much discussion around soy and its benefits or risks. The answer is, as always, mixed, as is the research.
Soy contains phytoestrogens, which are compounds that are similar in shape to estrogens (female hormones) in our bodies. These phytoestrogens are partial agonists, meaning they occupy estrogen receptors and activate them weakly while blocking stronger estrogen effects from animal products (who are fed hormones), the body, and xenoestrogens from plastics. This can protect from estrogen-related cancers.
Early puberty in girls (and cancer for that matter) is more strongly linked to animal products than to soy.
As a historical note, “The use of soy in the diet dates back to the Chinese Emperor Shen Nung in 2838 BC. Tofu (a protein-rich curd made from a hot water extract of soybeans) was developed in China and was introduced by Buddhist missionaries to Japan and Korea between the 2nd and 7th centuries.
Tofu was even a revered food of the Chinese Emperors in the Ming to Chin dynasties. Soybeans have been a staple in the diet of Southeast Asians for several centuries.” 
Soy has beneficial effects on PMS, menopause, heart health, bone density, and even preventing breast cancer, though there are two studies which indicate soy may not be safe in women who have had breast cancer.
The link to the article below is from a doctor I highly respect and who is the leading naturopath for women’s health in the US. She teaches gynecology to naturopathic students and has formed a company, Vitanica, which makes high quality herbal formulas. She is well known for having a solid handle on the research and making all of her clinical decisions with that in mind.
Check out the article- it is definitely written by someone who has looked at both sides and concluded that soy is safe and even beneficial in those who do not have breast cancer. That is, it is written positively toward soy, so read both that and statements against to form a balanced view.
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