Breast cancer patients often ask me, “Can I still eat tofu and other soy products?” . Previously, there was no clear statement on this issue because soy contains the phytoestrogen, soy isoflavones. Soy isoflavones are modulators of the estrogen receptor. That is, they have estrogen-like and anti-estrogenic effects. Estrogen is important in the development of breast cancer. As you know, the essence of endocrine therapy for breast cancer is to inhibit the action of estrogen. Therefore, at the breast cancer patient meeting in October 2009, I cautiously told the patient, “If your breast cancer is estrogen receptor positive (i.e. ER positive) and you are still taking triamcinolone, don’t eat more soy foods”. The latest research findings now show that the amount of soy foods consumed by breast cancer patients is significantly associated with a reduction in recurrence and mortality, meaning that eating more soy foods is beneficial for breast cancer patients. This latest clinical research on breast cancer was published in the December 9, 2009 issue of the Journal of the American Medical Association (JAMA) by physicians and scientists from Vanderbilt University and China’s Shanghai Institute of Preventive Medicine, and all are of Chinese or ethnic Chinese origin. The study included data from more than 5,000 patients in Shanghai who were diagnosed with breast cancer and had surgery between 2002 and 2006. A questionnaire was administered to each patient at 1-2 year intervals from 6 months after surgery. The survey was completed in June 2009. The average follow-up time was 4 years. After data analysis, it was found that the group of patients who ate the least amount of soy foods had a 4-year mortality rate of 10.3% and a recurrence rate of 11.2%, while the group of patients who ate the most amount of soy foods had a 4-year mortality rate of 7.4% and a recurrence rate of 8.7%. The latter group had a significant reduction! Further analysis also found that whether the breast cancer patients were estrogen receptor positive or negative, and whether the patients were taking triamcinolone or not, they showed a reduced risk of recurrence and death from eating more soy foods. Early studies have shown a lower incidence of breast cancer in people who eat more soy foods. And is there a benefit to eating soy foods when you have breast cancer? Including this study, there are only 2 studies worldwide that answer this question. The conclusions are the same. But this study is the one that includes the largest number of cases and has the most rigorous design to date. What is more meaningful is that this data is based on our Chinese breast cancer patients.