Given the abundance of vitamin and mineral supplements on the market today, it’s no wonder we swallow pills, gulp energy drinks, and chew protein bars at an alarming rate chasing the cure for cancer, turning back the hands of time or transforming our bodies into robust, lean-muscled machines. My pantry sports an arsenal of supplements recommended to correct nutritional imbalances as outlined in two tests I have taken over the past few years. Despite the testing, I wanted to know more about why I should take these supplements, particularly the antioxidants.
My quest started when I read an article in August’s News-Medical.Net about a new study at Brigham and Women’s Hospital and Harvard Medical School which concluded that middle-aged women at risk for heart disease don’t benefit from taking the antioxidant supplement combo of vitamins C, E and beta carotene. Why then, am I taking all three? Before rushing to the kitchen and tossing pill bottles in the trash, I thought I should dig a little deeper. I’m glad I did.
Studies by their nature have a narrow scope. It would be foolish to add more variables than are necessary because your research couldn’t conclude whether it was A, B or C that produced the results. Or maybe it was some combination of all three.
In the previously-mentioned study, researchers were only concerned with 1. heart disease, 2. antioxidant supplements and 3. middle-aged women at risk for heart disease. While I am not a risk for heart disease, I am a woman and I take antioxidant supplements. This study doesn’t consider two other factors that are important to me: can antioxidants be helpful to the body for other reasons and does an athlete have special needs?
What are antioxidants and what do they do?
Antioxidants are substances found in some vitamins and minerals which neutralize the oxidative effect of free radicals. Under normal circumstances, free radicals are essential for good health because they help fight infection and assist in the contraction of smooth muscles in the blood vessels. Left unchecked or when the body is under stress, free radicals can cause damage resulting in chronic disease, cancer, and cardiovascular disease. Free radicals can also damage cellular enzymes leading to cell damage and death which accelerates the aging process. Free radicals may also lead to eye diseases such as cataracts and macular degeneration. Antioxidants work by themselves and in concert with one another to fight any imbalance in the body.
Where do antioxidants come from?
Antioxidants are found in vitamins C and E and the beta carotene form of vitamin A. Fruits and vegetables are good sources of these vitamins.
Vitamin E is fat soluble and can be found in high-fat foods such as vegetable oils, avocados, nuts, seeds, wheat germ, and whole grains.
Vitamin C is water soluble and interacts with vitamin E to protect each other. Foods high in vitamin C are broccoli, oranges, strawberries, grapefruit juice, and red bell peppers and eating them raw is better.
Beta carotene, a form of the fat-soluble vitamin A, is found in fruits and vegetables with dark, rich colors such as carrots, pumpkin, sweet potatoes, winter squashes, cantaloupe, pink grapefruit, apricots, broccoli, spinach and other dark-green leafy vegetables.
What causes excessive production of free radicals?
A number of body “stressors” can cause free radicals to run amok, such as excessive or strenuous exercise, pollution, pesticides, cigarette smoke, and other environmental pollutants.
Endurance exercise can increase oxygen utilization from ten to twenty times over the resting state. The longer or more intense the workout, the greater the production of free radicals. Fortunately, our bodies adapt. Studies show that regular physical exercise enhances the antioxidant defense system and protects against exercise-induced free radical damage.
Those athletes most at risk for free radical damage are the “weekend warriors” because their sporadic activity level overwhelms the defenses. They are the ones who benefit the most from antioxidant supplementation.
Do well-trained athletes need supplementation?
While antioxidants don’t improve performance, they may counteract the side effects of high activity levels such as muscle soreness or respiratory infection.
Even if your diet is rich in antioxidants by consuming 8-9 servings of fruits and vegetables daily, you may still lack enough antioxidants to combat free radical damage. There is no definitive answer regarding supplementation, and the risks of long-term use of high doses of some antioxidants are unknown, but many sports nutrition experts such as Chris Carmichael and Joe Friel highly recommend supplementation.
The following are some guidelines for daily supplementation:
Vitamin C 500-1000 mg
Vitamin E 200-400 IU
Beta carotene 10 mg
Sources:
Carmichael, Chris. Food for Fitness. New York, NY: G.P. Putnam’s Sons, 2004.
Cordain, Loren, PhD and Joe Friel, MS. The Paleo Diet for Athletes. Rodale, Inc., 2005.
George Mateljan Foundation website, “World’s Healthiest Foods” at www.whf.org, September 3, 2007.
News-Medical.Net at www.news-medical.net. Vitamin supplements no benefit to women’s heart health. August 14, 2007.
Reavley, Nicola. The New Encyclopedia of Vitamins, Minerals, Supplements and Herbs. New York, NY: M. Evans & Co., Inc., 1998.
Website at www.rice.edu/~jenky/sports/antiox.html.
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