Walk-a-thons are major fundraisers for many charities, and breast cancer research and development is one of the top beneficiaries of this popular and increasingly star-studded activity. Just ask breast cancer survivors and fundraising veterans Sheryl Crow, Edie Falco, Cynthia Nixon and Robin Roberts, who have helped various breast cancer organizations raise millions of dollars. From 2003 to 2011, the Avon Walk for Breast Cancer raised more than $420 million.

But the (non-trans-fat) icing on the (carrot) cake is that the act of walking itself actually reduces your risk of developing breast cancer.

A recent American Cancer Society study looked at 73,000 women over the course of 17 years and found that, whatever your weight, walking about 3 miles in 60 minutes every day is solidly linked to lower breast cancer rates.

We say do it five to seven days a week, and aim for 10,000 steps a day! And as you go further and get stronger, pick up the pace. Stride out for three hours a week, and you moderately reduce your risk; hoof it seven hours a week, and you slash the risk of breast cancer by 14 percent compared with those who walk three hours or less a week.

But here's our favorite: If you start out walking seven hours a week and then ramp up your activity level so that you're really breaking a sweat with fast walking, aerobics, running or dancing, you cut your breast cancer risk by an astounding 25 percent. Now, that's doing more than talking the talk!