Resveratrol, a natural antioxidant compound found in red grapes, is found to counteract many cardiovascular health benefits of exercise, including reduced blood pressure and cholesterol, in older men, according to new research by University of Copenhagen (UC).

The previous studies conducted on animals revealed that resveratrol improved the cardiovascular benefits of exercise, following which the compound has been widely used as dietary supplement and as anti-aging compound.

Red wine and other foods with resveratrol were readily prescribed for cardiovascular health benefits.

However, the current study states that in older men the effect of resveratrol is reversed.

It suggests that antioxidants are not the solution for every problem and that some degree of oxidant stress may be required for the body to function properly.

UC PhD student and researcher Lasse Gliemann said they studied 27 healthy, physically inactive men around 65 years old for eight weeks.

"During the 8 weeks all of the men performed high-intensity exercise training and half of the group received 250 mg of resveratrol daily, whereas the other group received a placebo pill (a pill containing no active ingredient). The study design was double-blinded, thus neither the subjects nor the investigators knew which participant that received either resveratrol or placebo," Gliemann added.

"We found that exercise training was highly effective in improving cardiovascular health parameters, but resveratrol supplementation attenuated the positive effects of training on several parameters including blood pressure, plasma lipid concentrations and maximal oxygen uptake."

UC professor and project leader Ylva Hellsten said they were surprised to find that resveratrol supplementation in aged men blunts the positive effects of exercise training on cardiovascular health parameters, in part because their results contradict findings in animal studies.

"It should be noted that the quantities of resveratrol given in our research study are much higher than what could be obtained by intake of natural foods," Hellsten added.

Image: The resveratrol compound in red wine was supposed to provide cardiovascular health benefits. Photo courtesy of University of Copenhagen.