cnn: ibuprofen reduces breast cancer risk

Can taking aspirin or ibuprofen reduce your risk of getting breast cancer? One of the largest studies of its kind suggests that the answer might be yes.

In the past, researchers have flip-flopped on the issue, so they recently combined some of the best data - from 2.7 million women in 38 separate studies - to look for solid evidence. And they found it.

Women who took aspirin had a 13 percent lower risk of breast cancer than those who didn't, while those who took ibuprofen had a 21 percent lower risk.

The findings were published this week in the Journal of the National Cancer Institute.

While it might be tempting to try to reduce your own risk by popping these over-the-counter pain relievers, known as nonsteroidal anti-inflammatory drugs (NSAIDs), the researchers sound a note of caution: The pills can cause bleeding in your digestive tract. And some types of NSAIDs have been linked to risk of heart problems. Health.com: How aspirin can help your heart

"I would not recommend that women use NSAIDs for breast cancer prevention," says study author Bahi Takkouche, M.D., Ph.D., of the University of Santiago de Compostela in Spain. "NSAIDs may have very strong secondary effects. The results of this study just show that women who are taking NSAIDs for other reasons probably have a lower risk of breast cancer." Health.com: How to cut your breast cancer risk at any age

This type of study can't prove conclusively that NSAIDs are responsible for the lower risk of breast cancer. According to the experts, some other factor could be responsible for the reduction in cancer risk.