Teenage Exercise May Protect From Breast Cancer

WASHINGTON — Get your daughters off the couch: New research shows exercise during the teenage years — starting as young as age 12 — can help protect girls from breast cancer when they're grown. Middle-aged women have long been advised to get active to lower their risk of breast cancer after menopause. What's new: That starting so young pays off, too.

"This really points to the benefit of sustained physical activity from adolescence through the adult years, to get the maximum benefit," the study's lead author, Dr. Graham Colditz of Washington University School of Medicine in St. Louis, said.

Researchers tracked nearly 65,000 nurses between ages 24 and 42 who enrolled in the major health study.