Certain antioxidants like vitamin C and E may interfere with your efforts to live healthier. When you exercise, you retrain your body to process insulin, which can help protect you against diabetes and metabolic syndrome (read the full article in the New York Times).

What happens is that when you exercise you create muscle and those muscle cells burn extra glucose. Over time, exercise improve your insulin sensitivity - meaning that you need less insulin in your body. This is good, because if you become insensitive to insulin, you could eventually develop diabetes.

Exercise helps improve your insulin sensitivity unless you take antioxidants. What happens is that the vitamins and antioxidants you take interfere with the body’s own development of defenses and insulin sensitivity. The new recommendation is that if you exercise a lot, you should avoid taking too many antioxidant supplements.

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