Diet, exercise, and breast cancer:
Diet and exercise reduced serum markers for breast cancer in vivo, reduced tumor cell growth in vitro, and caused apoptosis of breast cancer cells in vitro. A study involving 38 overweight or obese postmenopausal women adhered to a low-fat (10-15% kcal from fat), high-fiber (30-40 g per 1,000 kcal/d) diet, and participated in a daily exercise class for 2 weeks. The diet and exercise was found to reduce several serum markers for breast cancer including estrogen, obesity, insulin and insulin-like growth factor-I (IGF-I), even while subjects remained overweight or obese. The in-vitro analysis used serum drawn from the study group before and after the 2 week intervention and placed it with cancer cells. It was found that the growth in different types of breast cancer cell lines was reduced by 6.6-18.5%. Cell death of several different cell types of breast cancer also increased by 20-30% after the intervention. (9)