Does diet, physical activity, or weight control have beneficial effects on cancer survival?

In the U.S., as of 2006, approximately 11,400,000 adults and children had cancer, and that number is expected to increase to nearly 17,000,000 by 2020.[1]

In an attempt to answer the above question as far as diet is concerned, and specifically about soy with its estrogen-like qualities, Shu et al[ 2] completed the Shanghai Breast Cancer Survival Study; it was population-based and involved 5042 breast cancer patients. They found that "soy food consumption was significantly associated with decreased risk of death and breast cancer recurrence, with adjusted 4-year mortality rates of 10.3% and 7.4% and 4-year recurrence rates of 11.2% and 8.0%, respectively, for women in the lowest and highest quartiles of soy protein intake. This well-designed study has a number of strengths, including detailed data on treatment, clinical characteristics, recurrence, vital status, and lifestyle habits, including diet."

References:

Ballard-Barbash R, Neuhouser ML.  "Challenges in Design and Interpretation of Observational Research on Health Behaviors and Cancer Survival." JAMA. Editorial. 2009;302(22):2483-2484. EXTRACT | FULL TEXT | PDF

1. Horner MJ, Ries LAG, Krapcho M; et al. SEER Cancer Statistics Review, 1975-2006. Bethesda, MD: National Cancer Institute; 2009. http://seer.cancer.gov/csr/1975_2006/. Accessed November 10, 2009.

2. Shu XO, Zheng Y, Cai H; et al. Soy food intake and breast cancer survival. JAMA. 2009;302(22):2437-2443. FREE FULL TEXT