Experts say couch potatoes face a higher risk after a clear link was established between a lack of exercise and the disease.
A study, published in the British Journal of Sports Medicine, found “strong evidence that greater levels of physical activity and less sedentary time are likely to reduce breast cancer risk, with results generally consistent across breast cancer subtypes”.
Researchers used data from 130,957 women of European ancestry.
Their results showed that overall activity was associated with about a 40 percent lower risk of breast cancer, while vigorous activity on three or more days a week was associated with a similar reduced risk of pre or perimenopausal breast cancer. Being sedentary was associated with a higher risk of some types of the disease.
The team, including experts from the University of Bristol, concluded: “More widespread adoption of active lifestyles may reduce the burden from the most common cancer in women.”