For people without heart disease, taking a daily aspirin to prevent heart attacks and strokes may increase the risk of severe brain bleeding to the point where it outweighs any potential benefit, a research review suggests. U.S. doctors have long advised adults who haven't had a heart attack or stroke but are at high risk for these events to take a daily aspirin pill, an approach known as primary prevention.\_61there's clear evidence aspirin works for this purpose, many physicians and patients have been reluctant to follow the recommendations because of the risk of rare but potentially lethal internal bleeding. For the current study, researchers examined datafrom 13 clinical trials testing the effects of aspirin\_62 a placebo ornotreatment in more than 134,000 adults. The risk of intracranial hemorrhage, or brain bleeds, was rare. One limitation of the analysis is that the smaller clinical trials examined a variety of aspirin doses up to 100 milligrams daily. The analysis also only focused on brain bleeds, and not on other types of internal bleeding associated with aspirin.63the benefits for preventing heart attacks, the consensus on aspirin has changed over time, particularly for people without heart disease or hardening and narrowing of the arteries. "We have previously recommended aspirin to prevent platelets from\_64the inside of an individual's arteries, but the benefit,while real, turns out to be small compared to the rare but devastating incidence of brain hemorrhage," the researcher said. "We no longer recommend routine use of aspirin in individuals who have no demonstrable cardiovascular disease or atherosclerosis."