Red wine - what's behind its healthy reputation?

In recent years, red wine has received some pretty good press. When we think of a healthy form of alcohol, red wine tends to be the top choice. But why - and does it deserve all the attention?
Scientists agree that there is something in red wine that, when drunk in moderation, can help to protect the heart, reduce 'bad' cholesterol and prevent blood clots. But there is little agreement of what is causing those beneficial effects.
Recently, Uruguayan chemists went to such great lengths to discover the secret of their healthy home-grown red wine that they sequenced the genome of the Tannat grape from which it is made. That was prompted by the discovery that those wines contained high levels of procyanidins - a class of flavanols found in plants, fruit and cocoa beans. Roger Corder, professor of experimental therapeutics at Queen Mary University of London and author of The Red Wine Diet, made the discovery and confirms that the Tannat wines contain three to four times more procyanidins than Cabernet Sauvignon. He says they - alongside the high concentration of tannins, which combat the ageing of cells - are likely to be behind its health-giving properties. Other scientists are excited about a compound found in the skin of red grapes called resveratrol.
For many years, it has been hailed as a kind of wonder drug - an anti-ageing compound, which could extend life, combat obesity and cure cancer. But, so far, studies on resveratrol have taken place in the lab - as yet there is no evidence that it can be effective in humans.