According to a new study conducted by Coyle Y. M. at the University of Texas Southwestern Medical Center in Dallas, TX, the lack of inactivity and physical exercise increases the risk of breast cancer.

"This is one of the first studies out that has shown that in women who do not have a history of breast cancer, that they can actually reduce their risk by exercising," said Dr. Susan K. Boolbol, a breast surgeon at Beth Israel Medical Center.

Exercise also decreases levels of estrogen and testosterone in the blood. These are the two sex hormones produced in both men and women that have been associated with uterine lining, prostate and breast cancers.

Exercise also burns fat, which can stores additional amounts of estrogen. Thus, the best way to keep breast cancer at bay is to keep obesity in control.

Research was carried on 32,000 women who enrolled in the Breast Cancer Detection Demonstration Project. A Follow-up Study was undertaken to check the link between risk of breast cancer and physical exercise.

Prior studies conducted by James McClain of the National Cancer Institute and colleagues, Michael F Leitzmann and colleagues at the National Cancer Institute confirmed and Freedman DM and colleagues from National Cancer Institute have also shown that people who did physical exercise regularly were at lower risk of developing cancer.