An ingredIent of red wine could explain the French paradox – or why people in France can eat as much fatty food as the British yet still run a lower risk of heart disease.

Scientists have identified a substance unique to red wine that could decrease the chances of coronary heart disease, even among gourmands who enjoy a rich diet of creamy sauces and red meat.

Several medical studies have found that heart disease is lower among people who consume moderate but regular tipples of alcohol but there also seems to be something special about red wine. A team of scientists from the William Harvey Research Institute at Queen Mary College, University of London, investigated whether red wine had a beneficial effect.

The scientists identified a group of compounds specific to red wine called polyphenols, which appear to depress the body's natural production of a substance called endothelin-1. This is known to be involved in increasing the risk of vascular disease and atherosclerosis (hardening of the arteries) by constricting the blood vessels.

The scientists found that polyphenols isolated from Cabernet Sauvignon red wine significantly decreased the production of endothelin-1 in bovine cells growing in a test tube, the journal Nature reports.

Professor Roger Corder, who led the team, said: "Our findings indicate that remarkably small amounts of red-wine extract can suppress endothelin-1 synthesis. Assuming adequate absorption of the active component, they support assertions that a moderate intake of red wine can prevent coronary heart disease."

* Taking up drinking in middle age can cut the risk of heart disease but it increases the chances of dying from other causes. Research published in the journal Heart today suggests that middle-aged people who take up regular, light drinking are less likely to have a heart attack or non-fatal heart disease than teetotallers. But they are 40 per cent more likely to die from cancer or other causes.