Study Finds Exercise Protects Against Cancer

A study of more than 25,000 Norwegian women suggests that regular exercise protects against breast cancer.

Compared with sedentary women, those who exercised at least four hours a week had a 37 percent lower risk of developing the disease, and the more women exercised, the less likely they were to get breast cancer, the investigators found.

The study follows more than a dozen smaller studies that found a similar effect, none of which, taken alone, was conclusive. So, with the weight of other evidence pointing in the same direction, several leading researchers said they would advise women to exercise even though the latest study was not definitive.