Exercise is associated with lower levels of estrogen in the body, which in turn can reduce breast cancer risk.
Older women who are physically active have lower levels of estrogen and its breakdown products in their bodies, according to a new study, perhaps explaining why exercise might reduce breast cancer risk.
Researchers long have linked exercise with lower breast cancer risk for women past menopause, believing it works partly by lowering their estrogen levels. Higher estrogen levels can raise breast cancer risk.
The new study provides more clues as to how the exercise might be protective, said Cher Dallal, a cancer prevention fellow at the U.S. National Cancer Institute. She is scheduled to ...