Virtually all middle-aged men and older women should be taking statins, the cholesterol-lowering drugs, if Britain is to have any real success in preventing heart attacks and strokes, experts say today.

The failure of successive governments to tackle Britain's unhealthy diet has resulted in such high cholesterol levels that one in three of Europe's obese children are British, say Paul Durrington, professor of medicine, from the Manchester Royal Infirmary, and colleagues.

But handing out drugs to large numbers of people, many of whom have previously been considered healthy, raises difficult questions. As with vaccinations, the policy would be to dose large numbers to prevent a minority from falling ill. But all drugs have side-effects and the cost would be a significant burden for the NHS - statins are already the biggest item in the drugs bill.

Writing in the medical journal Heart today, Prof Durrington and colleagues say they have compared the effectiveness of the policies on statins of the British, European and US health authorities in preventing cardiovascular disease - which leads to heart attacks and stroke. They say the current UK policy is the worst of all of them at preventing heart disease in the population.

The UK's national service framework (NSF) advises doctors to prescribe statins to those people whose risk of heart disease is greater than 30% over 10 years. This, says the paper, "stands out as the cheapest, but least effective, and in terms of making the best use of evidence for the benefit of the members of a healthcare scheme, the worst."

This policy targets resources at the group of people most likely to have a heart attack, so it is cost-effective. But they are far outnumbered by those in the population as a whole who have heart attacks and are not in this high-risk group, and who could be helped by statins.

Prof Durrington and colleagues say there are real difficulties "for a socialised healthcare system" in meeting the cost of a major medical advance such as statins, when it will have to be paid for either by increasing taxes or taking money away from other areas of medical treatment. Statins cost on average £152.52 a year per patient. In 2004, the NHS bill for statins was £769m. Some statins have been made available over the counter at high street chemists, but this has proved contentious, they say.

The National Institute for Clinical Excellence has recently recommended changing the threshold so that all those with a higher than 20% risk of heart disease are given statins on prescription. However, there is evidence that the drugs can benefit even those who have a 1% increased risk, say the doctors.

To be effective in preventing heart disease, "statin treatment must be provided for most men from middle age onwards and for most older women," they write.

There would be no need to discuss the medication of huge sections of the population, the authors say, if cholesterol levels in Britain were not so high. "The lack of resolve in tackling Britain's unhealthy diet as a consequence of anachronistic farming subsidies and a lack of government consistency in directing the food industry and encouraging physical education has resulted in one in three of Europe's obese children being British."

Cholesterol levels were coming down, but the decline halted between 1998 and 2003, as obesity increased, they say. "Renewed effort in this direction is therefore needed if the use of statins is not to extend to perhaps most of the population."

Peter Weissberg, medical director of the British Heart Foundation, said: "This paper suggests we must either treat many more people who are conventionally considered to be at relatively low risk of a heart attack, or we must be much more aggressive in our attempts to prevent the disease from occurring in the first place."

Millions reap benefit

About 2.5 million people are on statins. There are two types of cholesterol, "good" (HDL) and "bad" (LDL). Statins block the action of an enzyme in the liver which makes "bad" cholesterol from the fatty foods that people eat. They slightly raise the levels of "good" cholesterol. There are few side effects from statins; however cerivastatin, named Baycol, was withdrawn in 2001 after some people suffered a severe and sometimes fatal muscle reaction. One of the class, simvastatin, has been made available over the counter at low doses at high street chemists, which is controversial because statins need to be used with caution by people who have a history of liver disease or who drink alcohol heavily.