Two scientific articles in the July 2010 issue of American Journal of Clinical Nutrition shed more insight on the chemistry of red wine that may explain why more doctors are suggesting that a little red wine may be heart-healthy. Both articles focus on resveratrol, a chemical compound found in certain plants. It is called a phytoalexin because plants naturally produce it as an antibiotic substance to fight both bacteria and fungi. Plants containing resveratrol include the grapes and skins of grapes that produce wine, raspberries, mulberries, blueberries and cranberries. There is growing evidence that resveratrol plays a role in plaque development, fatty tissue growth, and other biological mechanisms that impact the cardiovascular system.
In the first article by Fischer-Posovszky et al reported that resveratrol influences adipose (fatty) tissue mass. Laboratory tests on human cells in vitro showed that resveratrol blocked immature fat cells from developing and differentiating affecting the fat cells' ability to function. These findings indicate that resveratrol might interfere with obesity and other metabolic effects that could increase the risk of cardiovascular disease.
In the second article, Hamed et al studied the effect of moderate red wine consumption on vascular endothelial function. Endothelial progenitor cells (EPC) are bone marrow-derived cells that are mobilized by the peripheral circulation when vascular repair is needed (e.g., peripheral arterial disease). In this study, 14 volunteers consumed 250 mL (little more than 8 ounces) of red wine daily for 21 consecutive days. The researchers reported an improvement on vascular endothelial function.
According to an editorial in the same journal, these findings may suggest that moderate wine consumption provides cardiovascular protection. However, these findings also raise further questions about whether red wine (resveratrol) can reverse or attenuate established heart disease. Human clinical trials are needed to substantiate these findings.
While we recognize the concerns about alcohol addiction, a surprising number of reports have come out in favor of moderate red wine drinking. In fact, a recent report suggested that a periodic glass of wine during a normal pregnancy may be helpful to the mother. It's hard for a layperson to determine what is hype and what is true. I recently came upon a website run by the Institute on Lifestyles and Health at Boston University that critiques many of the studies that discuss the benefits and risks of alcohol. It's web site can be found HERE.