Vitamins ‘can undo exercise benefits’

ANTIOXIDANT vitamins can undo some of the most important health benefits of exercise, research has shown.

Taking vitamins C and E after a workout appears to prevent physical exercise improving the body’s energy regulation, a study found.

Exercise is known to increase sensitivity to the hormone insulin, which governs the way cells use sugar as an energy source. Type 2 diabetes occurs when the body becomes resistant and less sensitive to insulin.

Some vitamins can block this beneficial effect of exercise, the findings suggest.

Ironically, it is the supplements’ health-boosting properties that appear to be to blame.

Vitamins such as C and E neutralise destructive “free radical” molecules called reactive oxygen species (ROS) that can damage cells and DNA, and speed up ageing.

These molecules are generated in larger numbers during vigorous exercise.

But the new research suggests that as well as causing damage, oxygen-free radicals also spur the body into becoming more sensitive to insulin. By mopping up the molecules, antioxidant vitamins cancel out this beneficial effect.

Dr Michael Ristow, from the University of Jena in Germany, and colleagues wrote their findings in the journal Proceedings of the National Academy of Sciences.