The benefits of the cholesterol-reducing drug statins are underestimated and the harms exaggerated, a major review suggests.
Published in The Lancet and backed by a number of major health organisations, it says statins lower heart attack and stroke risk.
The review also suggests side effects such as muscle pain do occur, although in relatively few people.
But critics say healthy people are unnecessarily taking medication.
The Lancet review, led by Prof. Rory Collins from the Clinical Trial Service Unit at the University of Oxford, looked at the available evidence for the effects of taking an average - 40mg daily dose of statins in 10,000 patients over five years.
It suggested cholesterol levels would be lowered enough to prevent 1,000 "major cardiovascular events" such as heart attacks, strokes and coronary artery bypasses in people who had existing vascular disease - and 500 in people who were at risk due to age or other illnesses such as high blood pressure or diabetes.
Prof. Collins said: "Our review shows that the numbers of people who avoid heart attacks and strokes by taking statin-therapy are very much larger than the numbers who have side-effects with it.
"In addition, whereas most of the side effects can be reversed with no residual effects by stopping the statin, the effects of a heart attack or stroke not being prevented are irreversible and can be devastating.
"Consequently, there is a serious cost to public health from making misleading claims about high side effect rates that inappropriately dissuade people from taking statin therapy despite the proven benefits."
Dr. June Raine, of medicines watchdog the Medicines and healthcare products Regulatory Agency said: "The benefits of statins are well established and are considered to outweigh the risk of side-effects in the majority of patients.
"Any new significant information on the efficacy or safety of statins will be carefully reviewed and action will be taken if required."
However, critics said the review was not the final word on statins.
Fiona Godlee, editor of the British Medical Journal, said: "This still does not address the calls for a thorough, independent review of the evidence of statins"
"This is especially important in view of the guidance which recommends that large numbers of healthy people should take a tablet every day."
London cardiologist, Dr. Assem Malhotra said: "There are serious question marks about the reliability of industry-sponsored studies on the side effects of statins, and essentially that's what this review is"
"Many of the scientists involved in the original studies were involved in this review. It is not an independent review."