Study: ‘Anti-aging’ antioxidant actually seems to undo effects of exercise

The red-wine polyphenol, resveratrol, believed to benefit longevity and heart health for its antioxidant properties, has been found to undermine the cardiovascular benefits of exercise in a small study.

In the July 22, 2013, issue of The Journal of Physiology, researchers led by Dr Lasse Gliemann at the University of Copenhagen report a needling wrinkle in the love affair with the wine antioxidant.

When some plants (like grape vines) are under stress, they produce the polyphenol which is often referred to as the “anti-aging” chemical.

Resveratrol has been shown to improve cardiovascular performance and extend the lives of non-mammals and mice – specifically improving the lipid profiles and longevity of mice who ate a lot of fat, due to its antioxidant effects.

The mice in that study got a boatload of resveratrol, though. Red wine has 1.5 to 3 mg of resveratrol per litre, so an average person would need to drink 1 000 litres of red wine daily to get that much.

Resveratrol does come in supplement form, but is that good for humans? Some believe that a certain amount of oxidative stress is necessary, so we shouldn’t drown ourselves in antioxidants.

METHODOLOGY: Twenty-seven healthy but physically inactive men (all 65 and older) undertook intense eight-week regimens of CrossFit and circuit training. Some took 250mg of resveratrol as well, and some took a placebo. The researchers monitored multiple metrics of cardiovascular fitness throughout the course of the exercise program.

RESULTS: By the end of the exercise program, the placebo group had a 45 percent greater increase in maximal oxygen uptake than the resveratrol group. The placebo group also saw a decrease in blood pressure, but the resveratrol group did not.

Levels of a vasodilator prostacyclin (a positive thing) were also lower in the resveratrol group, and the resveratrol group did not experience the positive effects on cholesterol and triglycerides that the placebo group did.

IMPLICATIONS: This is a small study, but it adds to a growing body of reasons to be skeptical of the divinity of antioxidants.

The authors’ interpretation: “These findings indicate that, whereas exercise training effectively improves several cardiovascular health parameters in aged men, concomitant resveratrol supplementation blunts most of these effects.”

Journal Reference:

Resveratrol Blunts the Positive Effects of Exercise Training on Cardiovascular Health in Aged Men

Authors: Gliemann L, et al. 

Journal J Physiol. 2013 Jul 22. [Epub ahead of print]