By Hannah Hoag

Girls, It's Never Too Early to Start Exercising

By Hannah Hoag

Mama, don’t let your girls grow up to be couch potatoes.

A mother’s loving touch should include a nudge onto the soccer field or into the pool. Girls and young women who exercise through their teens and early 20s can cut their risk of breast cancer.

One-quarter of all breast cancers are diagnosed before menopause. A May 21, 2008, study in the Journal of the National Cancer Institute found that women who ran, jumped, swam and danced in their youth had a reduced risk of early breast cancer.

The researchers followed nearly 65,000 women enrolled in a large research project known as the Nurses’ Health Study II. The women filled out questionnaires in which they indicated the amount of time they exercised between the ages of 12 and 34. Those who were physically active—3.25 hours per week of running or 13 hours per week of walking—had a 23-percent lower risk of pre-menopausal breast cancer than the least active women. “It’s our young girls who really need to be active,” says Leslie Bernstein, an epidemiologist at City of Hope, a comprehensive cancer center in Duarte, Calif. “Telling them to exercise is right on the ball.”

“The bottom line is: Being active is better than not being active, and the more you do, the better it is,” says Graham Colditz, one of the study’s authors, and the associate director of prevention and control at the Siteman Cancer Center at Washington University School of Medicine, in St. Louis. “You don’t have to run marathons.”