The results - which show that risks of major bleeding in low-dose aspirin users overwhelm any heart benefits - were reported online in the New England Journal of Medicine and presented Sunday at the European Respiratory Society International Congress in Paris.
Australian-American research has found the medication won't help you live longer or prevent your first heart attack, but it will increase the risk of bleeding in older people.
The study involved 19,114 people, mostly over the age of 70.
Until now, the balance between risks and benefits in older individuals was unclear, said Dr McNeil.
Professor John McNeil, one of the researchers at Monash University in Australia, told The Independent that despite the fact that aspirin has been around for more than 100 years, it was never clear whether healthy older people should take it as a preventative measure to keep them healthier for longer.
They were also at "significantly" increased risk of serious internal bleeding. There is substantial evidence that supports the daily use of aspirin for secondary prevention of heart disease, which means patients are prescribed the drug after they've already experienced a heart attack or stroke.
After almost five years, the researchers did not observe a difference between the two groups when it came to "disability-free survival". "The concern has been uncertainty about whether aspirin is beneficial for otherwise healthy older people without those conditions".
Clinically significant bleeding - hemorrhagic stroke, bleeding in the brain, gastrointestinal hemorrhages or other hemorrhages that required transfusion or hospitalisation - occurred in 3.8 per cent on aspirin and in 2.7 per cent taking the placebo.
Peter Rothwell, professor of neurology at the Centre for the Prevention of Stroke and Dementia at the University of Oxford, said taking the tablets if healthy, over the age of 70 and have not had a previous heart attack or stroke, is "really of very little benefit".More news: Pregnant Carrie Underwood Reveals She Had 3 Past Miscarriages
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"Clinical guidelines note the benefits of aspirin for preventing heart attacks and strokes in persons with vascular conditions such as coronary artery disease", said Richard J. Hodes, the director of the National Institute on Aging at the National Institutes of Health, which funded the study, in a news release.
The study was stopped early since the "wonder drug" that aspirin is generally believed to be, was not working.
While there were 21.5 cases of death, dementia or disability per 1,000 patients each year in the aspirin group, the rate was 21.2 with placebo. They did, however, document a higher rate of bleeding in the group that received aspirin, compared to the group that received a placebo.
When the McNeil team looked at death from any cause, aspirin still made no difference statistically, with a rate of 12.7 per 1,000 patients each year with aspirin and 11.1 with placebo.
The researchers said that has not been noted in previous studies and caution is needed in interpreting the finding.
There was also an increase in cancer deaths in the aspirin-treated group, which surprised the researchers.
Two other studies aimed to identify the effects aspirin can have on the body.
The study was coordinated at 34 sites in the US and 16 in Australia.