This is the VOA SpecialEnglish SCIENCE REPORT.

British scientists may have discovered the reason why red wineappears to protect the heart. They say natural chemicals found inred wine appear to protect against blocked blood passages. Thechemical substances are called polyphenols. They come from the outercovering of grapes. They are not present in other alcoholic drinks.

Researchers from the William Harvey Research Institute at theLondon School of Medicine and Dentistry carried out the study. Thefindings are published in Nature magazine.

The scientists say their discovery explains why many people insouthern Europe can eat fatty foods and still have a low risk ofheart disease. People in France, for example, have lower rates ofheart disease than Americans do. Yet the traditional French dietincludes butter, cheese and other foods high in cholesterol.

This led the British scientists to examine another important partof the French diet -- red wine. Several earlier studies havesuggested that people who drink moderate amounts of alcohol mayreduce their risk of heart disease.

The British team experimented with cells from the blood vesselsof cows. The scientists studied the effects of twenty-three kinds ofred wine on the cow cells. They found that polyphenols from all ofthe red wines stopped production of a protein called endothelin-one.This protein causes blood vessels to become smaller. Scientistsbelieve endothelin-one is linked to hardening of the blood vessels,which is a cause of heart disease.

The scientists found that the decrease in endothelin-one levelswas linked to the amount of polyphenols in the wines. The red wineknown as Cabernet Sauvignon seemed to have the greatest effect.

The British team performed similar experiments with two otherkinds of wine, white and rose. These wines contain little or nopolyphenols because the grape skins are removed before the wine ismade. White and rose wines had no effect on endothelin-one levels.

The scientists also studied the effect of non-alcoholic juicemade from red grapes. They found that grape juice slowed theproduction of endothelin-one, but was much less effective than thered wines.

The scientists say people who already drink wine might considerdrinking red wine to increase their protection against heartdisease.

This VOA Special English SCIENCE REPORT was written by GeorgeGrow.