Daily aspirin use has increased among U.S. adults, according to a survey published May 2015 in the American Journal of Preventive Medicine. The survey asked more than 2,500 people ages 45 to 75 about their current aspirin use. The overall use was 52%, up from 41% in a similar survey in 2004. The most common reasons for taking daily aspirin were prevention of heart attack and stroke. Eighteen percent of aspirin users cited cancer prevention as their reason for taking aspirin. And while most users said they’d talked to their doctor before starting aspirin therapy, 25% of the respondents had not. That finding is troubling, since aspirin is a blood thinner. “Aspirin can increase the risk of bleeding in the brain or elsewhere in the body. This risk might be justified if there is a good reason for aspirin use, but might be entirely unjustifiable if not. That is why I always recommend discussing any medication or supplement use with one’s primary care provider,” says Dr. Natalia Rost, associate professor of neurology at Harvard Medical School.