Should You Be Taking an Antioxidant Supplement?

Leaning on antioxidant-rich foods is generally safer and better for health. A dietitian explains why.

Isabel Vasquez is a bilingual registered dietitian practicing from an intuitive eating, culturally sensitive framework. Her clinical experience includes providing outpatient nutrition counseling to adults with a variety of chronic health conditions, along with providing family-based treatment for eating disorders in children and adolescents. She also offers intuitive eating coaching for Latinas to heal their relationships with food, particularly their cultural foods.

Maria Laura is EatingWell's senior nutrition & news editor. As part of the nutrition team, she edits and assigns nutrition-related content and provides nutrition reviews for articles. Maria Laura is a trained dietitian, almond butter lover and food enthusiast with over seven years of experience in nutrition counseling.

According to the National Center for Complementary and Integrative Health, antioxidants help prevent oxidative stress, which is thought to play a role in a number of health ailments, including cancer, cardiovascular disease, diabetes, Alzheimer's disease, Parkinson's disease and certain eye diseases. Vitamins C and E, selenium and carotenoids are examples of antioxidants that neutralize free radicals to help counteract the harmful effects of oxidative stress on the body. While they can be obtained from food, some people rely on antioxidant supplements to boost their antioxidant intake. However, research shows this may not be the best thing to do for your health. Learn what antioxidant supplements are, their effectiveness and the best antioxidant-rich foods to eat.

Antioxidants help prevent or delay oxidative stress from free radicals, per StatPearls. Free radicals result naturally from exercise and converting food to energy. According to the NCCIH, certain environmental contaminants can also be a source of free radical exposure, including cigarette smoke, pollution and even sunlight.Foods like fruits and veggies are great sources of antioxidants, but antioxidants can also be obtained through supplements. Antioxidant supplements are essentially highly concentrated doses of the given nutrient. Vitamins and minerals like vitamins C and E, selenium, manganese and carotenoids (like beta carotene, lycopene, lutein and zeaxanthin) are considered antioxidants, per the NCCIH.

Antioxidant supplements often come in powder, pill or liquid form. They can be purchased as a single nutrient supplement—like a vitamin C supplement—or as a multivitamin that includes a bunch of vitamins and minerals, including antioxidants.

As surprising as it may be, research does not support health benefits from antioxidant supplements, per the NCCIH. Antioxidant-rich foods, like fruits and veggies, have many health benefits, but supplements, not so much.

Even with foods, the National Institutes of Health notes that there's more to learn about the specific role naturally occurring antioxidants play and how they impact your health.

We do know, however, that higher fruit and veggie consumption is linked with reduced risk of cardiovascular disease (per a 2020 study in the Journal of the American Heart Association), lower mortality (per a 2021 study in Circulation) and breast cancer (per a 2021 study in the British Journal of Cancer), to name a few of their health benefits.

Although antioxidant supplements aren't shown to be beneficial to health, they may be helpful if you have a deficiency. For example, if you are deficient in vitamin C, a vitamin C supplement may help normalize your vitamin C levels and prevent unwanted side effects of a deficiency. According to the NIH, these could include delayed wound healing and gum inflammation. That's not to say that you'll reap added antioxidant benefits; you'll ensure your body has enough of the nutrient to meet its basic needs for optimal functioning.

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was a large clinical trial conducted by the National Cancer Institute that concluded in 2011. Participants who had been taking 400 IUs of vitamin E per day (over 1,800% of the Daily Value) for 5.5 years had a 17% higher incidence of prostate cancer 1.5 years after supplementation ended compared with participants who took a placebo. Researchers determined this difference to be statistically significant and not just related to chance.

In the same study, participants taking selenium with or without vitamin E also had a higher incidence of prostate cancer; however, this difference was not statistically significant.

Beta carotene supplementation has been found to increase the risk of lung cancer in people who smoke. A 2019 study in Nicotine & Tobacco Research with over 29,000 participants examined whether the tar and nicotine content of cigarettes affected cancer risk with beta carotene supplementation, and they found that it did not; all levels of nicotine and tar content paired with 20 milligrams/day of beta carotene supplementation increased lung cancer risk.

Before starting any supplement, it's best to talk with a health care provider to be sure it won't interact with any medications you're taking. Here are some examples of how antioxidant supplements can potentially interact with medications:

To boost your antioxidant intake, we recommend leaning on food sources. The best sources of antioxidants are fruits and veggies, but dark chocolate, green tea and nuts are other good sources. Here are some ideas to give your meals and snacks an antioxidant boost:

In general, antioxidant supplements are unnecessary for healthy people without a nutrient deficiency. They are not shown to have the same health benefits as consuming antioxidant-rich foods like fruits and vegetables. So, it's best to focus on eating more plant foods rich in naturally occurring antioxidants.

Since antioxidant supplements don't have the same research-backed benefits as antioxidant-rich foods, you probably don't need to take an antioxidant supplement at all, let alone every day. That being said, if you are deficient in an antioxidant like vitamin C or E, daily supplementation is usually recommended to replenish your levels of the nutrient and reverse or prevent side effects from a deficiency.

The most powerful antioxidant supplement is the one you are deficient in. If you don't have a deficiency in a specific antioxidant nutrient, then you probably won't benefit from taking a supplement. And you'd be better off focusing on incorporating more antioxidant-rich foods in your diet. Antioxidant-rich foods, like fruits and veggies, are associated with loads of health benefits and no safety concerns, whereas supplements may lead to harm when overdone or taken with certain medications.

Antioxidant supplements are linked with health issues in certain populations. Since they contain highly concentrated doses of nutrients, they may increase the risk of toxicity. They can also interact with medications, potentially decreasing the medication's effectiveness or exacerbating its effects. Antioxidant supplements are also expensive, so they can put an unnecessary dent in your wallet.

Despite how alluring antioxidant supplements may be, research shows that they don't really benefit health unless you're deficient in the given nutrient. That being said, adding more antioxidant-rich foods to your diet can benefit your health in numerous ways since antioxidant-rich foods are also rich in nutrients like fiber, which have a plethora of health benefits.