The Oxford University study, which involved about 175,000 people and was published in The Lancet, found taking statins regularly cuts the risk of a heart attack or stroke by a fifth in those who have no sign of the disease.
Currently, the only people considered at high risk, those with a one-in-five chance of having a heart attack in the next 10 years, are given the cholesterol-lowering drugs.
But the researchers said treatment guidelines should be reviewed in light of the findings, and there should also be a blanket policy of prescribing all over 50 people statins which can cost as little as USD 1 for one month.
Study co-author Prof Colin Baigent said: "If we want to prevent heart attacks and strokes that come out of the blue in people with no previous evidence of problems, then we have to identify and treat people who are currently healthy but are known to be at increased risk."
"Such treatment should, of course, be in addition to obvious things like encouraging better diet, more exercise and avoidance of cigarette smoking," Prof Baigent was quoted as saying by the Daily Telegraph.
In the study, the researchers analysed data from 175,000 people in 27 random trials which compared people on statins with those on a dummy pill.
They found that for every one-point reduction in levels of bad cholesterol in the blood, there was a 21 per cent reduction in the risk of serious events, including heart attacks, strokes or surgery for blocked arteries among those with no symptoms of heart disease.
The risk of dying from a heart attack or stroke among those at lowest risk was cut by 15 per cent. For every 1,000 people in the low-risk group treated with statins for five years there would be 11 fewer major heart attacks or strokes.
"A benefit that greatly exceeds any known hazards of statin therapy," the authors said. (More)