Healthy people should not take aspirin to prevent a heart attack because the risks outweigh the potential benefits, experts have warned.
Several studies have concluded that aspirin can help to ward off a second heart attack or stroke in patients who have already had one. Millions of Britons are believed to take a daily dose of the medication to act as an insurance against health problems.
But after carrying out a review of research, Dr Ike Iheanacho said in a medical journal editorial that people with no signs of cardiovascular disease (CVD) should not use the drug as a preventative measure because of the risk of internal bleeding of the stomach.
It follows a study by British scientists earlier this year which warned that daily aspirin could do more harm than good among people who have not already had a heart attack or stroke.
In the latest expert advice, Dr Iheanacho stressed that patients who have already had cardiovascular problems should continue to take aspirin if they have been prescribed the medication. But the article, published in the Drug And Therapeutics Bulletin (DTB), calls on doctors to review giving aspirin to other people, such as diabetics and those with high pressure.
Dr Iheanacho, editor of the DTB, said: "Current evidence for primary prevention suggests the benefits and harms of aspirin in this setting may be more finely balanced than previously thought, even in individuals estimated to be at high risk of experiencing cardiovascular events, including those with diabetes or elevated blood pressure.
"Overall, we believe that the currently available evidence does not justify the routine use of low-dose aspirin for the primary prevention of CVD in apparently healthy individuals, including those with elevated blood pressure or diabetes; this is because of the potential risk of serious bleeds and lack of effect on mortality."
June Davison, senior cardiac nurse at the British Heart Foundation, said: "It is well established that aspirin can help prevent heart attacks and strokes among people with heart and circulatory disease - so this group of people should continue to take aspirin as prescribed by their doctor.
"However, for those who do not have heart and circulatory disease the risk of serious bleeding outweighs the potential preventative benefits of taking aspirin. We advise people not to take aspirin daily, unless they check with their doctor.
"The best way to reduce your risk of developing this disease is to avoid smoking, eat a diet low in saturated fat and rich in fruit and vegetables and take regular physical activity."