Basics The Health Benefits of Antioxidants By Shereen Lehman, MS Shereen Lehman, MS Shereen Lehman, MS, is a healthcare journalist and fact checker. She has co-authored two books for the popular Dummies Series (as Shereen Jegtvig). Learn about our editorial process Updated on May 22, 2020 Fact checked by Sean Blackburn Fact checked by Sean Blackburn LinkedIn Sean is a fact-checker and researcher with experience in sociology and field research. Learn about our editorial process Print Seb Oliver / Getty Images Table of Contents View All Table of Contents Benefits of Antioxidant-Rich Foods Drawbacks of Supplements Avoid Large Doses 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 related carotenoids, vitamins C and E, plus various phytochemicals such as lycopene, lutein, and quercetin. Benefits of Antioxidant-Rich Foods You can find these antioxidants in many different foods, some of which you may already enjoy eating. There are large amounts of antioxidants in fruits, vegetables, nuts, and whole grains and smaller amounts of antioxidants in meats, poultry, and fish. Junk foods, such as highly processed fast foods tend to be much lower in antioxidants. No surprise. 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. Differences Between Whole Grains and Refined Grains Drawbacks of Supplements Antioxidants are available as dietary supplements, but research doesn't indicate that these supplements are beneficial. While research supports increasing your intake of dietary sources, the results are not as impressive when the individual antioxidants are extracted and studied alone. Antioxidant extracts often show remarkable results in laboratory studies (test tubes, lab dishes, and sometimes in lab animals), but when they're 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 advanced stages of age-related macular degeneration. Overuse and Interactions Can Undermine Health Benefits of Supplements Avoid Large Doses 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 of cardiovascular disease and cancer. Taking large doses of vitamin E (over 400 International Units per day) has been associated with a possible increase in overall mortality. But, this risk doesn't apply to a typical multivitamin supplement. The amounts of vitamins A and E included in multivitamin tablets are small in comparison. A Word From Verywell If you're thinking about taking larger amounts of any antioxidant supplements, you should speak with a healthcare provider first. Was this page helpful? Thanks for your feedback! Looking to lose weight? Our nutrition guide can help you get on the right track. Sign up and get it free! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 3 Sources Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Aune D, Keum N, Giovannucci E, et al. Dietary intake and blood concentrations of antioxidants and the risk of cardiovascular disease, total cancer, and all-cause mortality: a systematic review and dose-response meta-analysis of prospective studies. Am J Clin Nutr. 2018;108(5):1069‐1091. doi:10.1093/ajcn/nqy097 U.S. Department of Health & Human Services. Antioxidants: In depth. Updated November 2013. Pohl F, Kong thoo lin P. The potential use of plant natural products and plant extracts with antioxidant properties for the prevention/treatment of neurodegenerative diseases: In vitro, in vivo and clinical trials. Molecules. 2018;23(12). doi:10.3390/molecules23123283 Additional Reading Academy of Nutrition and Dietetics. What Is an Antioxidant? The United States National Institutes of Health, National Cancer Institute. Antioxidants and Cancer Prevention: Fact Sheet. United States National Institutes of Health, National Center for Complementary and Alternative Medicine. Antioxidant Supplements for Health: An Introduction.