Choose the right red wine for a healthy heart

If you plan to visit France this summer, be sure to try a bottle or two of Madiran. The appellation, which is just within sight of the Pyrenees, produces what may be the healthiest wine in the world. Madiran, made with at least 40 per cent tannat grapes, is deep purple, tannic and delicious with a bowl of hearty vegetable soup. And its levels of a plant chemical that is essential for heart health are among the highest of any wine.

Madiran wine can be bought in Britain through a few specialist merchants, but it is generally regarded as too tannic for we British, who are more accustomed to the highly processed, over-sweet, easy-drinking wines of the New World.

To Roger Corder, these wines from the Gers region of south-west France have a special appeal. Corder, a pharmacologist and Professor of Experimental Therapeutics at the William Harvey Research Institute at St Bartholomew's Hospital in London, was drawn to the region by a puzzle that has long taxed doctors: why is it that the French eat a diet with similar levels of fat to ours, and have similar levels of blood cholesterol, yet four Britons die of heart disease for every one Frenchman?

Doctors traditionally put this so-called French Paradox down to something present in red wine, but not in white, that protected the heart. But this did not satisfy Corder. If red wine is protective, why does it work better in some parts of France than others? The Gers region has twice the French national average of men aged 90 or more. Are some wines more protective than others?

So it has proved. When he analysed the wines of the Gers, Corder found that they contained high levels of a plant chemical (or polyphenol) called procyanadin. This was partly thanks to the area's grapes, and partly to the region's old-fashioned production methods that involve a long fermentation and maceration process.

Previous research by scientists, including Corder - his first paper on the subject was published in Nature in 2001 - had shown that drinking wine high in procyanadins improved the function of the lining of the blood vessels and protected against atherosclerosis, the thickening of the artery wall.

This is critical for heart health. All the risk factors we know about - high blood pressure, high cholesterol, lack of exercise - damage the lining of the blood vessels and makes them more prone to "furring up" with fatty deposits. Procyanadins appear to counteract this effect by improving the elasticity of the blood vessels. But where to find procyanadins? Though they are abundant in cranberries and dark chocolate, modern wine-making methods often eliminate them. This is an issue for the consumer, who may mistakenly believe that all red wine is healthy.

Corder has published his findings in a book, The Wine Diet, based on his research over a decade. "My central message is for the consumer to be more discerning. People think they are doing themselves good by knocking back quantities of red alcoholic plonk. The wines to look for [with high levels of procyanadins] are those with firm tannins made in the traditional way. It is not just about Madirans. There are plenty of choices out there from other parts of the world. What I would like to see is wines produced that are less alcoholic, less sweet, more tannic and more traditional."