The soy conundrum: Does soy raise or reduce breast cancer risk?
This is a study that makes alot of sense to me. Let me know your thoughts.
Soy beans and soy foods contain Isoflavones- and act as “phytoestrogens”, which means that they bind to the same cell receptors as estrogen. This has led to the hypothesis that soy foods could prevent the cell proliferation that leads to breast cancer. (This is how tamoxifen helps prevent re-occurrence of breast cancer.)
However, the few human studies conducted to date do not support this hypothesis. And the results of animal tests suggest that one soy isoflavone (genistein) may interfere with the ability of tamoxifen to curb the growth of breast cancer cells.
Instead, research to date suggests that exposure to isoflavones in childhood or early adolescence may be protective. It appears that the cancer-preventive effects of soy foods only manifest if the developing mammary gland was exposed to dietary isoflavones during childhood and puberty.
This hypothesis would explain why Japanese women – who eat tofu from early childhood and throughout life, in modest amounts – have a much lower rate of breast cancer compared to western women.
It’s been feared that when women only begin to consume isoflavone-rich soy foods or supplement powders later in life – especially at the time of menopause – the phytoestrogenic isoflavones in soy could actually stimulate the proliferation of endometrial and mammary gland tissues, with unknown and unpredictable risks.
So the finding that isoflavones obtained from soy foods enhanced survival rates in mature breast cancer patients offers some hope for women who only began consuming tofu, tempeh, or soy milk after their adolescence.
So, despite the positive association between high intake of soy flavonoids and enhanced breast cancer survival, consuming lots of soy foods or soy protein supplements may not be a terribly wise prevention tactic … unless the soy habit starts early in life and is practiced in moderation.
Source:
http://newsletter.vitalchoice.com/e_article000961729.cfm?x=b68Pq10,b1kJpvRw,w
Something to think about: soy has become ever-present in our lives. And in its processed, most unnatural forms. For example, if you read labels, you’ll find soy flour, as a protein enhancer, in practically all breads. Soy oil is used for so much restaurant frying, etc. Is this realy good for us?