Our bodies make some of the antioxidants we need. Additional antioxidants come from foods such as fruits and vegetables. Some antioxidants, such as vitamins C, E, and curcumin, are also available as dietary supplements.
Antioxidant supplements often come in a powder, pill, or liquid form. They can be a single nutrient supplement—like a vitamin C supplement—or a multivitamin with other vitamins and minerals.
When Should You Take an Antioxidant Supplement?
These supplements can be useful if you suffer from an antioxidant deficiency (see I told you we’d come back to it). A diet high in unhealthy fats, sugar, and/or refined carbohydrates can lead to antioxidant deficiency and increased oxidative stress (8). A diet that lacks lean meats, fruits, vegetables, nuts, and seeds can also lead to insufficient antioxidant levels.
Age also plays a factor in antioxidant deficiencies. As you age, your body naturally produces fewer antioxidants, and their ability to fight off free radicals and oxidative stress weakens (9). Certain antioxidant supplements can help replenish your levels.
Who Shouldn’t Take Antioxidant Supplements?
While antioxidant supplements can be great for those with deficiencies, studies have shown that high-dose antioxidant supplements may be harmful in certain populations.
For example, a 2011 study linked vitamin E supplementation with an increased risk of prostate cancer in healthy men (10).
Participants who had been taking 400 IUs of vitamin E per day (over 1,800% of the Daily Value) for five and a half years had a 17% higher incidence of prostate cancer after supplementation ended compared with participants who took a placebo. Researchers determined this difference to be statistically significant and not just related to chance.
Similarly, studies have linked beta-carotene supplementation with an increased risk of lung cancer in smokers (11).
Some antioxidant supplements—such as vitamin A—may even increase the risk of birth defects if taken in high doses (12). If you are pregnant, always check with your doctor before you start taking any regular supplements.
Certain antioxidants can also interact with certain medications:
- Vitamin C supplements could counteract the HDL cholesterol-raising effects of statin drugs (13).
- Vitamin E supplements could increase the risk of bleeding when taken with anticoagulant or antiplatelet medications like warfarin (14).
- Vitamin A or beta carotene supplements can increase the risk of vitamin A toxicity if you take oral retinoid medication, such as acitretin for psoriasis or bexarotene for T-cell lymphoma (15).
You should always consult with your doctor or healthcare provider before adding any new supplement into your routine.