New research questions the value of low-dose aspirin for the prevention of heart attacks, strokes, dementia and cancer among healthy older adults. The study of more than 19,000 older individuals found that taking aspirin 100 mg or a placebo every day for a median of 4.7 years did not reduce the risks of cardiovascular disease, dementia, or disability. Furthermore, the risk of significant bleeding in the digestive tract, brain or other sites that required transfusions or admission to the hospital increased. The findings are published online in three articles in the New England Journal of Medicine. Lead author John McNeil, MD, of Monash University in Melbourne, Australia, advised healthy older people: "If you don't need it, don't start it." But he noted that people who have already been using it regularly should not stop based on the study results, suggesting that they discuss the matter with their doctors. McNeil also cautioned that the new results do not apply to individuals who have already had heart attacks or strokes, as aspirin inhibits clotting.