Soy Intake and Risk of Breast Cancer

The increasing prevalence rate of breast cancer among Asian-American women shows the more significant role of lifestyle factors in etiology than genetic factors. The search engine PubMed was used for searching related paper by “breast cancer”، “soy”، “isoflavones”، “phytoestrogen” as the key words. We selected papers which published during 1990 to 2012. Various experimental studies reported the protective role of soy protein and soy isoflavone for breast cancer. However، some studies showed that soy isoflavone induces cell proliferation in vitro and interacts with tamoxifen effects. Indeed، epidemiological studies showed conflict findings. The rate soy is consumed by Asian has protective effect on breast cancer. Soy consumption should provide 20-50 mg of isoflavones per day to protect against breast cancer. Soy consumption during childhood had more beneficiary effects rather than adolescent and adulthood، and during adolescent is more favorable than adulthood