Red Wines New research from the William Harvey Research Institute and the University of Glasgow shows that red wines from areas of greater longevity in southwest France and Sardinia have higher levels of procyanidins - a type of flavonoid polyphenol with potent protective effects on blood vessels. A number of population studies have revealed that moderate drinkers of red wine have less heart disease than non-drinkers. As a result it has become widely accepted that a glass or two of red wine per day is good for your heart. Writing in the 30 November issue of Nature, Professor Roger Corder from Queen Mary's William Harvey Research Institute, and Professor Alan Crozier from the University of Glasgow, explain the importance of 'traditional' style red wines for conferring the protective effects of procyanidins. "The endothelial cells which line our arteries are an important site of action for the vascular protective effects of polyphenols," explains Corder. "We purified the most biologically active polyphenols, and identified them as procyanidins." Procyanidins are the most abundant flavonoid polyphenols in red wine - up to 1 gram per litre is found in some traditional style red wines. Red Wines from France and Sardinia The team tested wines from two specific regions in southwest France and Sardinia, associated with increased longevity, to see if they differed to wines sourced from other countries across the world. The 'traditional' wines revealed surprisingly high levels of procyanidins, with often five to 10 times more than some new world wines. The results suggest that while a glass or two a day can benefit your heart, not all red wines provide the same amount of heart protecting polyphenols. Professor Corder concludes: "The traditional production methods used in Sardinia and south western France ensure that the beneficial compounds, procyanidins, are efficiently extracted. This may explain the strong association between consumption of traditional tannic wines with overall wellbeing, reflected in greater longevity." Q&A on Red Wine Study How did you carry out the research? How much procyanidins would you have to consume to feel the benefits? Note on Resveratrol Do the benefits differ between men and women? Why did you look at red wines from areas of higher longevity? What gives the wines their higher concentration of procyanidins? Is it just the wine-making methods? How does this differ to other areas of the world? Does the grape variety have any effect on the procyanidin levels? Could other vineyards develop these techniques and grape varieties to make 'healthier wine'? Winemakers already know how to make these wines, but they are more difficult to make and more costly, so not the type of wine that most mass market winemakers will choose to make. Can you recommend any particular wines/vintages that we should be drinking over Christmas/New Year? Are procyanidins found in any other foods?
A: It was a laboratory study where we used cultured cells to screen for biological activity and then purified the most potent polyphenols found with this screening test for identification by mass spectrometry.
A: It is difficult to say as further work is required in clinical trials but the best evidence comes from clinical trials of grape seed extract, which have shown that 200 - 300 mg per day will lower blood pressure. Two small glasses (125 ml glass) of a procyanidin-rich red wine, such as a Madiran wine from southwest France, would provide this amount.
Resveratrol is often put forward as a key component of red wine, both in terms of reducing heart disease and increasing longevity (see: Kaeberlein & Rabinovitch Medicine: grapes versus gluttony. Nature 2006 Nov 16; 444: 280-1). But the levels of this polyphenol are so low (typically 1 – 2 mg/litre) that to consume sufficient daily amounts of resveratrol it would be necessary to drink around 1000 litres of wine per day.
A: Not that we know; however women are more sensitive to the adverse effects of alcohol with an increased risk of breast cancer. Consuming other foods or non-alcoholic drinks containing these procyanidins should also be considered as an option.
A: There is a 19th century expression "A man is only as old as his arteries" – which can be taken to mean that those with the healthiest arteries live longer. Since the most important protective effect of procyanidins we can show in the laboratory is on arterial function, our hypothesis was that areas of greater longevity might have a protective dietary factor, which could include the type of wine that was drunk. So it was of great interest to us when we found both in Sardinia and in southwest France that the wines made in these in areas had higher levels of procyanidins.
A: Numerous factors affect the procyanidin content of wine – but the most important is generally the winemaker, who can influence the selection of grapes based on ripeness, the contact time between seeds and skins with the fermenting juice (or must), and whether any fining or filtration is done to make the wine smoother and less tannic. Traditional wines frequently have a 3 – 4 week fermentation and maceration with seeds and skins, resulting in full extraction of procyanidins. Whereas modern style wines may only have a few days fermentation with seeds and skin (usually less than a week), which is only just enough time to extract the colour from the skins. If over ripe grapes are used to make the wine these have less procyanidins and higher sugar. So you end up with a type of red wine that is sweeter, higher in alcohol, and has almost no procyanidins. These are the wines that are everywhere now, and which are described as having smooth tannins or ripe tannins.
A: Yes it can do - a good example is the tannat grape grown in southwest France, which can produce the most procyanidin-rich wines, but requires much more skilful winemakers to make well structured wines. Cabernet sauvignon and Nebbiolo grapes also make good wines with high amounts of procyanidins but only if the winemaker uses techniques that favour full extraction.
A: 'Healthier wine' is a difficult concept because too many people over indulge on smooth, sweet, very alcoholic wines, when smaller quantities with meals is the only pattern of wine drinking that is associated with health benefits. But in the sense that higher procyanidin consumption could be achieved while drinking less wine (less is more!), then these wines need to be more readily available.
A: Madiran wines are the best choice but difficult to find in the UK.
A: dark chocolate, apple, cranberries.
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