A daily dose of aspirin cuts women’s risk of developing a particular type of breast cancer by 16 percent, new study reveals.

Aspirin is a common non-steroidal anti-inflammatory drug that can be used to relieve symptoms of arthritis and prevent second heart attacks and other ailments. Previous studies have revealed that it may also protect against colorectal cancer. However, aspirin is also known for causing serious side effects in some people including ulcers and bleeding.

Scientists at the U.S. National Institutes of Health in Rockville, Maryland, studied 126,124 women aged between 51 and 72, healthy at the beginning of the research in 1995. By the time the follow-up period ended in 2003, 4,501 of the women developed breast cancer. However, researchers found that women who took aspirin daily were 16 percent less likely to develop the so-called estrogen receptor (ER) positive breast cancer. In 75 percent of breast cancers, tumors are fuelled by the female hormone estrogen.

"Even though it's a small reduction in relative risk, since ER-positive breast cancers are the more common types, if this result is confirmed to be true it could have potentially a big public health impact. Our results provide support for further evaluating relationships in prospective studies with well-defined measures of NSAID use by NSAID type... and by ER status," Gretchen Gierach of the National Cancer Institute, part of the NIH, lead-author of the study, said, as quoted by Reuters.

Liz Baker, science information officer at Cancer Research UK, said any woman considering taking aspirin regularly should consult their doctor first. "It's important to remember that taking aspirin for a long time can have harmful side-effects, including heart problems and stomach ulcers. Weighing up the risks and benefits, it's too soon to recommend aspirin as a way of reducing the risk of cancer. Cancer Research UK would urge people to speak to their doctor before taking aspirin regularly," she said according to the Telegraph.co.uk.

The study appeared in BioMed Central’s open-access journal Breast Cancer Research.