Nutrition Blog: Antioxidants

What are antioxidants good for? 

Antioxidants are substances that may protect cells in your body from free radical damage that can occur from exposure to certain chemicals, smoking, pollution, radiation, and as a byproduct of normal metabolism. Dietary antioxidants include selenium, vitamin A and the related carotenoids, vitamin C, and vitamin E, plus various phytochemicals such as lycopene, lutein, and quercetin.

You can find these antioxidants in many different foods; there are large amounts of antioxidants in fruits, vegetables, nuts, and whole grains. There are smaller amounts of antioxidants in meats, poultry and fish.

Since antioxidants can protect the cells in your body from damage, consuming foods rich in antioxidants may be good for your heart health and may also help to lower your risk of infections and some forms of cancer. The best way to increase your antioxidant intake is by eating more fruits and vegetables; they're rich in many nutrients and fiber along with the antioxidants, and they're usually low in calories.

Antioxidants in Supplements

Just about any antioxidant you can find in your food is also available as a dietary supplement, but research doesn't indicate much benefit with the use of antioxidant supplements. While research supports increasing your intake of dietary sources of antioxidants, the results are not as impressive when the individual antioxidants are extracted and studied alone. They often show impressive results in laboratory studies (test tubes, lab dishes and sometimes in lab animals). However, when antioxidant supplements are used in human clinical trials, the results for disease and death prevention have been disappointing. One exception was the National Eye Institute study of age-related eye disease, which suggested that a combination of antioxidants reduced the risk of developing advance stages of age-related macular degeneration.

Some antioxidant supplements may be detrimental to your health when taken in large doses and may interact with certain medications. Large amounts of vitamin A supplements may cause birth defects when taken by pregnant women, and may increase your risk for cardiovascular disease and cancer. Large doses of vitamin E (over 400 International Units (IU) per day) has been associated with a possible increase in overall mortality. This doesn't apply to a typical multivitamin supplement;he amounts of vitamins A and E included in multivitamin tablets are in small doses, and are okay. But if you're thinking about taking larger amounts of any antioxidant supplements, you should speak with a health care provider first.