What are antioxidants?
Antioxidants are compounds that neutralize free radicals, the unstable molecules that can damage cells.
If free radicals are sparks from a fire, antioxidants are the people with water buckets. A few buckets keep things safe. Drench the whole campsite and you might put out the fire you actually needed for cooking.
Why it matters for aging
Your body makes its own antioxidant enzymes and gets others from food, such as vitamin C, vitamin E and plant compounds called polyphenols. They help keep free radicals in balance.
The problem with megadose pills is that free radicals aren't only harmful. They also act as signals, for example telling muscles to adapt after exercise. Flooding the body with antioxidants may blunt some of those useful signals. In a large trial, men taking high-dose vitamin E even had more prostate cancer. Balance, not maximum, is the goal.
A common myth
Taking high-dose antioxidant pills slows aging and prevents disease.
A review of 78 trials found antioxidant pills didn't help people live longer, and beta-carotene and vitamin E were linked to slightly higher death rates. Antioxidant-rich foods like fruit and vegetables are still good for you, for many reasons.
Go deeper
Deep dives
- The best supplements for longevity, graded by evidence
- The first part of you to break isn't in your nucleus
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Updated Nov 9, 2026 · All terms