London: Healthy people who take aspirin as an 'insurance policy' against heart attacks could be doing more harm than good.

A British study has found that daily use of aspirin almost doubled the risk of dangerous internal bleeding, while having no effect on heart attacks or strokes. The results will add to the confusion around the drug.

Millions are prescribed low-dose aspirin after a heart attack or stroke and there is pressure for 'blanket prescribing' to all middle-aged people, with one report suggesting most healthy men over 48 and women over 57 would benefit.

But concern has been mounting over the 'worried well' who take it, often without being aware of side-effects that can include internal bleeding. An analysis in The Lancet medical journal earlier this year found that healthy people who took aspirin reduced their risk of heart attack or stroke - already small - by some 12 per cent.