Red Wine Compound Health Benefits Questioned
October 27, 2012

Red Wine Ingredient Resveratrol May Offer No Health Benefits For Some

redOrbit Staff & Wire Reports - Your Universe Online

Bad news for wine connoisseurs hoping to garner some extra health benefits from their alcoholic beverage of choice. New research demonstrates that one of the ingredients found in red wine may not be as beneficial to healthy women as previously believed.

Experts at the Washington University School of Medicine in St. Louis recruited 29 post-menopausal females who were not suffering from type 2 diabetes and who were otherwise in reasonably good health. Their goal was to study the effectiveness of resveratrol, which is believed to improve insulin sensitivity.

Over a three month period, half of those women consumed an over-the-counter resveratrol supplement, while the other half was given a placebo. While previous studies suggested that the substance could improve a person's metabolic function or be used to treat or prevent certain diseases (including cancer, cardiovascular disease, or diabetes), senior investigator Samuel Klein said that their study demonstrated that "resveratrol supplementation does not have metabolic benefits in relatively healthy, middle-aged women."

"Few studies have evaluated the effects of resveratrol in people," Klein, the director of Washington University's Center for Human Nutrition and a Professor of Medicine and Nutritional Science, said. "Those studies were conducted in people with diabetes, older adults with impaired glucose tolerance or obese people who had more metabolic problems than the women we studied. So it is possible that resveratrol could have beneficial effects in people who are more metabolically abnormal than the subjects who participated in the study."

Klein and his associates gave 15 of their subjects 75 milligrams of resveratrol daily -- roughly equivalent to what they would get by consuming 8 liters of red wine. Fourteen others were given sugar pills. Both groups were then evaluated for their insulin sensitivity, the rate of glucose uptake in their muscles, and their metabolic response to varying doses of the substance.

"We were unable to detect any effect of resveratrol," Klein said. "In addition, we took small samples of muscle and fat tissue from these women to look for possible effects of resveratrol in the body's cells, and again, we could not find any changes in the signaling pathways involved in metabolism."

However, wine drinkers should not discount the health benefits of their beverage of choice just yet.

"The purpose of our study was not to identify the active ingredient in red wine that improves health but to determine whether supplementation with resveratrol has independent, metabolic effects in relatively healthy people," the senior author explained. "We were unable to detect a metabolic benefit of resveratrol supplementation in our study population, but this does not preclude the possibility that resveratrol could have a synergistic effect when combined with other compounds in red wine."

Klein's study was published Thursday in the journal Cell Metabolism. The research was funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), as well as from grants provided by DSM Nutritional Products, the Longer Life Foundation, the Japanese Research Foundation for Clinical Pharmacology, the Manpei Suzuki Diabetes Foundation and the Kanae Foundation for the Promotion of Medical Science.