Just a little bit of exercise is enough to decrease the risk of breast cancer, according to a new study.
However, University of North Carolina in Chapel Hill researchers said that the best way to lower your risk of breast cancer is to get to a healthy weight and maintain it.
The study, published in the journal CANCER, included 1,504 women who had breast cancer (233 of them had noninvasive breast cancer, while 1,271 people had invasive breast cancer), as well as 1,555 women who didn't have breast cancer. All of the women were between ages 20 and 98.
The researchers found that reproductive-age or postmenopausal women who reported exercising the most in the study -- between 10 and 19 hours each week -- were the ones who had the greatest decrease in breast cancer risk -- a 30 percent lower risk of the disease.
However, even women who exercised less than that seemed to have a decrease in breast cancer risk, especially for the hormone-receptor positive kinds of breast cancer.
And you don't have to be a marathoner or super-exerciser to reap the benefits -- researchers found that all levels of exercise intensity were linked with a decreased risk.
"The observation of a reduced risk of breast cancer for women who engaged in exercise after menopause is particularly encouraging given the late age of onset for breast cancer," study researcher Lauren McCullough said in a statement.
But the important thing is to maintain the healthy weight -- researchers found that if a woman stayed active but put on significant pounds, breast cancer risk increased -- suggesting weight gain can actually negate the positive effects of exercise.
Similarly, TIME magazine reported on a Fred Hutchinson Cancer Research Center study showing that women who experienced a moderate weight loss -- as a result of eating healthily and exercising -- also had a decrease in hormones linked with breast cancer.