Moderate drinkers in good health should not be discouraged from drinking by doctors according to researchers. In fact a 16-year study of nearly 9,000 men in the US showed that moderate drinking lowered their risk of heart attack.

The studies showed that men who drank around one and a half to three units of alcohol every day on average demonstrated nearly a third of the risk of suffering heart attacks than healthy teetotallers. One unit is a glass of wine or a half-pint of beer.

Eric Rimm at Harvard school of medicine in Boston said, "We only looked at really healthy people, but even beyond their already low risk, people who drink moderately can lower their risk of [heart attack] still further. [Doctors] should not tell them to stop drinking."

For their study Dr Rimm's team selected 8,867 of the healthiest men from a study of more than 50,000 healthcare professionals. All the men were non-smokers with a BMI of less than 25, with a regular exercise routine and a healthy diet. The study began in 1986 with the researchers monitoring the subjects' self-reported alcohol consumption and incidents of heart attacks during the following 16 years. 106 of them died of a heart attack.

The study revealed that men who averaged between zero and one unit of alcohol a day suffered a similar risk of heart attack to teetotallers, while those who drank three units a day or more had a slightly reduced risk.

Most impressive was the protection from heart attack that was seen in men who drank moderately. An average of 0.5 to 1.5 units a day nearly halved the risk compared with abstainers, while those who drank between 1.5 and 3 units a day suffered nearly a third of the risk. The results of the study appear in the current issue of Archives of Internal Medicine.

Dr Rimm said alcohol increased levels of the "good" cholesterol HDL in the blood and reduced the risk of clotting.