Antioxidants

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Treatment Overview

Antioxidants are natural chemicals that protect the body from damage caused by harmful molecules called free radicals. Many experts believe that this damage is a factor in the development of cancer and other conditions.

You are exposed to free radicals:

  • Through by-products of normal processes that take place in your body. Examples include burning sugars for energy and releasing digestive enzymes to break down food.
  • When the body breaks down certain medicines.
  • Through pollutants.

Antioxidants include some vitamins (such as vitamins C and E), some minerals (such as selenium), and flavonoids, which are found in plants. The best sources of antioxidants are fruits and vegetables. You can find flavonoids in fruits, red wine, and teas. You can also buy antioxidant supplements. But it's best to get antioxidants from a healthy diet.

Why It Is Used

Antioxidants may play a role in the management or prevention of some medical conditions, such as some cancers, macular degeneration, Alzheimer's disease, and some arthritis-related conditions.

Risks

Until more studies are done, it's best to get your antioxidants from a diet rich in fruits and vegetables rather than from supplements. Taking supplements in high doses can be harmful. No single antioxidant alone can protect the body.

The U.S. Food and Drug Administration (FDA) doesn't regulate dietary supplements in the same way it regulates medicines. A dietary supplement can be sold with little or no research on how well it works.

Always tell your doctor if you're using a dietary supplement or if you're thinking about combining a dietary supplement with your standard medical treatment. This is especially important if you are pregnant or breastfeeding.

Related Information

Credits

Current as of: September 20, 2023

Author: Healthwise Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.