Exercise and Breast Cancer

When it comes to breast cancer, walking saves lives. And not just 5K walks for charity.

New research released today shows that post-menopausal women who walk for as little as an hour a day have a 14 percent lower risk of breast cancer. More exercise leads to an even greater risk reduction, the study showed.

The findings come as the nation celebrates Breast Cancer Awareness Month, and thousands take to the pavement to raise millions of dollars for research in Making Strides Against Breast Cancer.

Read More: Breast Cancer Basics

The American Cancer Society study, led by senior epidemiologist Alpa Patel and published in Cancer Epidemiology, Biomarkers & Prevention, looked at more than 70,000 post-menopausal women from 1992 to 2009. Almost half the women said that walking was their only fitness activity.

“For women who find it daunting to begin an exercise regimen, the encouraging news is you don’t have to become a marathoner to impart benefits to your breast cancer risk—a leisurely walk every day can help,” Patel told Healthline. “Because walking is the most common exercise activity, more studies are looking at the independent benefits of walking on disease risk and finding that it helps with increasing longevity, lowering cardiovascular disease and diabetes risk, and lowing the risk of some cancers, like colon cancer.”

Regular Exercise Is Crucial

Dr. Tufia Haddad, an oncologist at the Mayo Clinic who was not involved with this research, told Healthline the results will likely create a buzz. “There have been a number of smaller studies showing somewhat similar results, but with this one really gives us concrete data,” she said.

She said that encouraging women to get regular exercise is extremely important. “We hope this message is getting out into the primary care community," Haddad said. "They're really the ones who do the really hard work of caring for patients and doing their best to keep them healthy.”

Too often, Haddad said, the emphasis is placed on family medical history when it comes to measuring a patient's breast cancer risk. “On the contrary, most breast cancers are sporadic, and there is no familiar pattern. I think we need to refocus our energy on doing what we can do proactively,” she said.

Haddad stressed that regular exercise is good for cancer survivors, too, and that exercising is the single biggest lifestyle factor for reducing relapse and increasing survival rates.

Learn More: Famous Women Who've Won the Battle Against Breast Cancer

America Gets Moving

Federal guidelines recommend that adults get a minimum of two and a half hours of moderate-intensity exercise per week, with the caveat that more exercise brings even greater health benefits. 

Patel said walking sets off several physiological processes that can result in lower breast cancer risk, including sex hormone production, improved glucose metabolism, and a reduction in chronic inflammation.

Getting America to walk has become a national movement, with organizations around the U.S. dedicated to increasing walkabillity. Carl Sundstrom, program manager at the Pedestrian and Bicycle Information Center at the University of North Carolina, said cities around the country are sinking money into making their infrastructures more walkable.

And research shows that property values go up when communities become more walkable, Sundstrom told Healthline. “What really sells is the economic side of things. But walkable communities do get people out of their house and interacting with their neighbors. They're getting that physical health benefit, but also that mental health benefit,” he said.

Marge Lee of Ocean Grove, N.J. is a post-menopausal woman with risk factors for breast cancer. She walks two miles a day and works hard to stay healthy.

“I remember sitting in my doctor’s office last year and saying that I was finding that my busy work schedule was making it difficult for me to maintain my habit of walking two miles a day,” she told Healthline. “He looked me in the eyes and said, firmly, 'Then consider walking to be part of your business agenda for the day, because keeping healthy is part of your job.'”