Antioxidant supplements do not extend life, and high-dose vitamin E and beta-carotene slightly increase the risk of death. This finding is consistent across multiple large analyses, including a broad systematic analysis from 2024. Only in the case of a confirmed deficiency is targeted supplementation a different consideration; preventive use provides no benefit and carries a real risk at high doses.
Antioxidant supplements are one of the best examples of an idea that looks scientifically promising but disappoints in practice. The evidence, including a broad 2024 systematic analysis, points consistently in the same direction: they do not extend your life, and with high-dose vitamin E (400 IU per day or more) and beta-carotene there are serious signals that they slightly increase the risk of death. That is not a theoretical footnote, but something researchers found repeatedly across multiple large analyses.
The mechanism behind the disappointment is intriguing: antioxidants from vegetables, fruit and tea are indeed beneficial, but when you single out one substance and pack it into a high-dose pill, that substance behaves differently in the body. Beta-carotene is particularly risky for smokers, in whom supplements were shown to increase the risk of lung cancer.
One exception is worth mentioning: if a doctor identifies a confirmed deficiency, targeted supplementation is a different situation from taking pills preventively out of caution. But if you are considering antioxidant supplements for your health or a longer life without such a deficiency, the conclusion is clear: the effort and money yield nothing, and with the most heavily dosed forms you are taking a real risk. Eating more vegetables and fruit does give you the benefits that people once attributed to these pills.
Moderate evidence, 2 source(s); the direction is likely but not firmly proven.