A new prospective cohort study adds to the evidence that regularly taking aspirin reduces the incidence of cancers and cancer mortality. But the study, in postmenopausal women in the US Midwest, found that use of non-steroidal anti-inflammatory drugs did not protect against cancer.

Researchers from the Mayo Clinic College of Medicine in Rochester, Minnesota, and the University of Minnesota in Minneapolis studied 22 507 postmenopausal women who had no history of cancer or heart disease and who took part in the Iowa women's health study. They presented their …