Soya diet in reducing the risk of breast cancer

Some epidemiological studies indicate that early life exposure to phytoestrogens may be critical for breast cancer prevention. Clinical studies to define the effect of phytoestrogens on breast cancer are underway. Soya contains many chemopreventive components. The soya diet used in clinical and laboratory studies contains isoflavones: genistein and daidzein, mostly as conjugates. The mechanisms of phytoestrogens’ action were presented. Phytoestrogens are weak estrogens “in vivo“ but their mixed estrogen agonist/ /antagonist properties are very important. The action of phytoestrogens is not confined to specific mechanisms involving estrogens. They affect numerous biochemical targets in cells that are associated with estrogen receptors. Many investigations have shown that genistein inhibits 17b-estradiol as well as the epidermal growth factor-stimulated growth of MCF-7 cells. Many other alternative mechanisms of action of genistein and daidzein have been described. The clinical studies and concerns to evaluate the use of phytoestrogens as preventive agents for breast cancer have been reported.
In summary, a diet containing soya and weakly estrogenic isoflavones is effective in reducing circulating levels of ovarian hormones in premenopausal women. Because decreased levels of ovarian hormones may reduce breast cell proliferation and breast cancer risk, the results of clinical and laboratory studies have implications for breast cancer prevention by dietary intervention.