Health benefits of Soy products
Soy products like tofu contain several types of phytoestrogens. These are weak, nonsteroidal estrogens that could help prevent both breast and prostate cancer by blocking and suppressing cancerous changes.
Also, there are a number of isoflavones in soy products, but research has shown that genistein is the most potent inhibitor of the growth and spread of cancerous cells. It appears to lower breast-cancer risk by inhibiting the growth of epithelial cells and new blood vessels that tumors require to flourish and is being scrutinized as a potential anti-cancer drug.
There are however, some precautions to consider when adding soy to your diet. Eating up to 4 or 5 ounces of tofu or other soy a day is probably ok, but research is being done to see if loading up on soy could cause hormone imbalances that stimulate cancer growth. As a precaution, women who have breast cancer or are at high risk should talk to their doctors before taking pure isoflavone powder and pills, extracted from soy.
A Harvard study found that a diet high in soy can lead to erectile dysfunction in men due to the fact that the bean’s estrogenic properties decrease testosterone levels.