Resveratrol is a polyphenol type flavonoid currently exciting great interest as a potential boon to health. Like other flavonoids and polyphenols, it is a very useful anti-oxidant in its own right, but resveratrol has attracted particular attention as a potential solution to the so-called "French Paradox".



This is the term used to describe the phenomenon, which has long been a puzzle to medical science, by which rates of cardiovascular disease in France have remained low relative to those in the rest of the developed world, despite the widespread national consumption of a diet high in animal fat and cholesterol, and a firmly entrenched tobacco habit. Of course France also enjoys many of the benefits of the so-called Mediterranean diet through its high intake of fresh fruit and vegetables, oily fish and olive oil, but there are good reasons to think that the consumption of red wine may be the real explanation of the apparent paradox.

It is known in any case that the moderate consumption of alcohol has a significant protective effect on the cardiovascular system, reducing disease by as much as 20-30%, but conventional medical opinion is characteristically cautious in acknowledging that the resveratrol in red wine may have any benefits over and above those which would in any case be provided by the alcohol. However, the role of fat-soluble anti-oxidants in protecting the circulatory system from damaging free radical attack is well understood, and it would therefore appear that the resveratrol and other polyphenols contained in red wine can only be beneficial. Laboratory tests, moreover, have shown resveratrol to have significant anti-coagulant and anti-inflammatory effects.

For the purposes of obtaining your intake of resveratrol from wine you need to know that it's contained principally in the skins of red or black grapes, and is consequently found in significant quantities only in those wines produced by an initial pulp fermentation which allows the developing alcohol to leach both colour and other substances, including resveratrol, from the skins. It follows that the longer this pulp fermentation is allowed to continue the more resveratrol the wine will contain. So the colour of the wine is a handy guide. Generally, the richer and darker the colour of the wine the more resveratrol will be found. Rose types and light reds may contain some, but white wines produced by a juice fermentation alone will provide little if any.

Usually it is the red wines produced in the sunnnier climates close to the Mediterranean, and the New World, which will be richest in resveratrol, and dark red wines of this type may provide as much as 2 mg of resveratrol in a small 5 oz glass. But unfortunately from a health point of view, these also tend to be the strongest in alcohol and the so-called "congeners" which accentuate hangovers.

But fortunately for those who dislike red wine, or are concerned about alcohol intake, other sources of resveratrol are available. The amount in foods varies widely, but the best sources are peanuts and red grapes, both of which may provide anywhere between 0.3 and 1.3 mg of resveratrol per cup. Bilberries and cranberries may also be a useful source.

Supplements of resveratrol are also now readily available, principally in the form of red wine or red grape extracts, which will also contain other anti-oxidant polyphenols. Manufacturers' recommended doses will typically provide between 10 and 50 mg of resveratrol, which would require a very high, and potentially hazardous, level of wine consumption to achieve regularly.

That said, there is no known toxicity from taking resveratrol, as such, although its blood thinning properties will tend to inhibit the blood's clotting ability and resveratrol is therefore not recommended for those taking anti-coagulant drugs such as warfarin, or certain types of anti-inflammatory including aspirin. Needless to say, however, toxicity problems of a different kind may occur if alcoholic drinks are used to excess as the principal or only source.

But as noted above, moderate consumption is generally recognised to be beneficial to health, particularly for the cardiovascular system. So the message seems to be: if you want to enjoy a couple of glasses of wine with your dinner then go right ahead. And have that age old pleasure enhanced by the knowledge that the resveratrol it contains is also doing you some good.