Soy and Breast Cancer

Soy foods, rich in plant estrogens, have been embraced by American women seeking relief from menopause without the breast cancer risk associated with synthetic hormones. Because Asian women consume soy-based diets but have a low incidence of breast cancer, it has been suggested that soy prevents cancer, perhaps by reducing estrogen levels. Asian women living in Asia have serum estrogen levels as much as 40% lower than U.S. women and demonstrate a fivefold lower risk of developing breast cancer. The link between soy and cancer prevention is far from conclusive, though, as Kerrie B. Bouker and Leena Hilakivi-Clarke of Georgetown University's Lombardi Cancer Center in Washington, DC, demonstrate with their summary of research on soy's effects on the breast [EHP 108:701-708]. The researchers suggest that for postrmenopausal women in the United States, soy may actually have estrogenic effects. ~~~~~~~~~~~~~~~~~~~1