Doctors often tell women diagnosed with breast cancer not to eat soy products or soy supplements because these foods or supplements can interfere with anti-estrogen therapy. However, a new study announced at the American Association for Cancer Research’s 2015 Pennsylvania Annual Meeting found that regular consumption of soy foods can actually reduce the risk of breast cancer recurrence. In the new study, Lena K. Hirakovich, a professor of oncology at the Lombardi Comprehensive Cancer Center in Georgetown, USA, said that the risk of breast cancer recurrence was reduced by eating soy foods regularly. Blacklake Vee? Clark and colleagues completed a study on the association between soy products and breast cancer in laboratory rats. It was found that in rats fed soy (specifically soy isoflavones), the T-cell immune response was activated prior to the start of tamoxifen treatment (an anti-estrogen treatment). In addition, attempts by breast cancer tumors to avoid immune system attack by hiding themselves during treatment were thwarted. The new findings suggest that patients can still continue to consume soy products during breast cancer treatment. Professor Clark’s analysis notes that many doctors believe that soy isoflavones stimulate breast cancer cell growth and undermine anti-estrogen therapy. However, the latest findings suggest that the ability of soy isoflavones to activate anti-tumor immune responses and reduce the expression of immunosuppressive mechanisms could explain why lifelong intake of soy isoflavones could reduce breast cancer recurrence rates.