Until recently, research on the heart-protective benefits of grapes has focused mainly on wine and grape juice. But what about grapes eaten fresh, known as table grapes?
A growing body of research suggests that the polyphenols in wine and juice - polyphenols also found in table grapes - are largely responsible for the benefits.
In a study published in the Annals of the New York Academy of Sciences, researchers at the University of Connecticut tested whether grapes and their component polyphenols are also heart-protective. They found that table grapes from California protected the heart and blood vessels against oxidative tissue damage, in a way similar to the well-known effects of red wine.
Table grapes and wine contain many of the same polyphenols - disease-fighting phytonutrients such as resveratrol, anthocyanins, catechins, and quercetin.
In this new study, researchers confirmed that grape polyphenols are effective antioxidants in two ways. Grape polyphenols scooped up and inactivated free radicals. Grapes also reduced by half the production of malondialdehyde, a by-product of oxidation.
In the same study, researchers tested the protective effect of the polyphenol-rich grapes in a model that mimics what happens during and after a heart attack. California table grape consumption improved blood flow and heart pumping capacity, and reduced the area of tissue death after a heart attack. Researchers attributed these effects mainly to the antioxidant effect of grapes.
For years, researchers have told us that drinking wine is good for the heart. More recently, grape juice was shown to help reduce susceptibility of LDL to oxidation and blood's tendency to form clots. This latest research shows that fresh grapes also provide antioxidant protection.
(Shanghai Star January 7, 2003)