One study, in the September 2008 issue of The Journal of Nutrition, found that drinking either red or white wine in moderation leads to increased blood plasma levels of resveratrol. In the small clinical trial, 20 healthy men and women in their 40s were divided into two groups: One drank 10 ounces a day of red wine for 15 days; the other drank 10 ounces of white wine daily.
At the end of the trial period, blood tests showed that both groups had higher plasma levels of resveratrol. Both groups also showed increases in nitric oxide production a potential marker of cardiovascular health. The research team, led by investigators at the University of Perugia in Italy concluded that resveratrol stimulates nitric oxide production in the blood's platelets, which may protect the cardiovascular system by aiding the transmission of nerve impulses, transporting oxygen into the tissues, dilating blood vessels, and preventing blood-clot formation.
Now animal research backs up white wine's potential cardio-protective effects. A study published in the Aug. 13, 2008, issue of the Journal of Agricultural and Food Chemistry found that feeding white wine to lab rats protects against heart attack. Tests even showed increased functional recovery in white-wine treated rats.
An antioxidant in white wine known as tyrosol—rather than resveratrol—could be responsible for the protective effect, says Nilanjana Maulik, Ph.D., whose team led the research at the University of Connecticut Health Center in Farmington, Conn.
CR's Take: The potential benefit of red and white wine applies only to people who drink moderately: one drink a day for women, two a day for men. Drinking more than that can raise blood pressure, make certain cancers more likely, and trigger emotional and family problems.
—Doug Podolsky, senior editor