Antioxidant Pills Reduce Exercise Benefits

The current issue of Journal of the American College of Sports Medicine shows that antioxidant pills prevent the major mitochondrial benefits of athletic endurance training (Medicine & Science in Sports & Exercise, June 1, 2011). Rats that trained on a treadmill increased the enzymes that are necessary to increase the number and size of mitochondria. Rats who trained on a treadmill and were given two powerful antioxidants, vitamin E and alpha lipoic acid, did not increase the enzymes that are necessary to increase the number and size of mitochondria.

How humans get their energy for exercise: Humans convert food to energy most effectively in the mitochondria, hundreds of small chambers inside muscle fibers. They need oxygen to do this. The limiting factor to how fast and long you can move is the time it takes to move oxygen into muscle fibers. Athletic training makes you faster and gives you greater endurance by enlarging and increasing the number of mitochondria in muscles.

Antioxidant pills can harm: People who take 1000 mg/day of vitamin C and 400 IU/day of vitamin E do not gain the benefits of increased insulin sensitivity when they exercise (Proceedings of the National Academy of Sciences, May 12, 2009).

• When blood sugar levels rise too high, sugar sticks on the surface of cell membranes and can never get off. The attached sugar is converted in a series of chemical reactions to sorbitol that destroys cells.

• Contracting muscles help to prevent this damage by removing sugar so fast from the bloodstream that blood sugar levels do not rise too high.

• Food is converted to energy to power your muscles by a series of chemical reactions that shuffle electrons from molecule to molecule.

• This occurs primarily in the mitochondria, small energy-producing chambers in cells, that number anywhere from a few to thousands in each cell.

• As electrons are shuffled to produce energy, extra electrons can accumulate. They can either end up on hydrogen atoms to form water and become harmless, or they can end up on oxygen atoms to form free radicals that can damage cells. This can cause cancers, heart attacks and other life-shortening conditions.

• Exercise speeds up the reactions that turn food into energy, so exercise increases the production of free radicals.

• The body responds to this increased production of free radicals during exercise by producing tremendous numbers of antioxidants that sop up the free radicals and render them harmless.

• Exercise prolongs life and prevents heart attacks and cancers by causing the body to dispose of free radicals by the increased production of antioxidants.

Let the buyer beware: If you exercise and take antioxidant vitamins C and E, you prevent your own body from making large amounts of antioxidants during exercise, so more free radicals (oxidants) accumulate in your body and more cells are damaged.

Many studies show that:

• Taking large doses of beta carotene (pro-vitamin A) increases risk for heart attacks in men and increase risk for lung cancer in smokers.

• Taking large doses of vitamin C does not prevent colon cancer, and does not prolong life in people with cancer.

• Taking large doses of vitamin E or selenium does not prevent lung cancer, heart disease or stroke.

My recommendations: Exercise every day, and get the antioxidant vitamins and other nutrients your body needs from foods, not from pills. Eat a wide variety of foods including large amounts of fruits, vegetables, whole grains, beans, nuts and other seeds. If you want to take Recommended Dietary Allowances of vitamins in pills, go ahead; there is little evidence that you will harm yourself. However, when you take large doses of any vitamin, you don't have the foggiest idea whether you are harming or helping yourself. I do not recommend large doses of vitamins to anyone.