People asking about soy milk lately. Soy good or bad? Causes cancer or not? Soy is quite popular in the US. It comes if forms of whole soybeans (edamame), soymilk, soybean oil, tofu, tempeh, miso, and many vegetarian meat and dairy substitues. Soy has gotten bad press lately because soy products are made up of isoflavones. Isoflavones are phytoestrogens and it has been hypothesized that this extra estrogen would excessive; thus, increasing the risk of cancers, specifically breast cancers. Studies DO NOT support this. In fact, studies show that people who eat soy may have a decreased risk of cancer compared to those with no soy in their diets. There was a 2012 analysis of 9514 women from US and China. Those people who took in the most soy had a 25% less likelihood of developing recurrent cancer. There is data to suggest soy eaters have less prostate, colon and breast cancers. This may be in part due to the fact that those isoflavones are phytoestrogens but have an opposite effect than previously suspected. These phyoestrogens may actually block the effects of estrogens. Importantly though, soy has shown benefit in estrogen negative cancers as well.
There is also concern about male fertility. Studies show that soy does not have an adverse affect on male hormones (testosterone). Soy infant formulas will not affect the babies’ reproductive health. There is also a role in inflammation. Inflammation is the source of most chronic illnesses. One thousand Chinese women who ate more soy had less inflammation. Soy reduced hot flashes in menopause as well!
It is okay and in fact good to eat soy!! But please remember whole soy products are the best; i.e. edamame, soymilk, tofu, miso. Remember, studies were not done on the processed soys: like soy protein isolates. Processed foods come with their issues and the soy protein isolates have some questionable health benefits. Also we need to consider the role of genetically modified soybeans. Try to eat non-GMO soy. But, Enjoy soy. Dont be afraid to have your kids drink it. It is all good! Now, dont overdo it because you think it will decrease your risk of cancer. Just eat it as a great protein and nutrient source as you desire but dont overdo it!