In today's Health Matters, staying trim and in shape could reduce your risk of breast cancer.

A recent study by the Women's Health Initiative showed women who walked just 30 minutes a day lowered their risk of getting the deadly disease by 20 percent. Another study by the American Cancer Society found women who gained up to 30 pounds after the age of 18 were 40 percent more likely to get breast cancer.

That's compared to women who didn't pack on the pounds. Women who put on an extra 70 pounds after the age of 18 doubled their risk.