What are antioxidants, and do supplements prevent disease?
Antioxidants help limit certain oxidative reactions, but are not a guaranteed shield against cancer or ageing. A varied diet supports health; that does not mean high-dose antioxidant supplements reproduce the benefits of food.
Details
Food offers more than one compound
Vegetables, fruit, nuts and other foods supply multiple compounds, fibre and nutrients. Variety matters more than chasing the highest antioxidant number on a label. The body also regulates oxidation through its own systems.
When supplements can harm
High-dose supplements have not established general disease prevention and can be harmful in specific settings. Beta-carotene increased lung cancer risk in trials involving smokers or asbestos-exposed people. Some supplements may interact with medicines or cancer treatment.
Use for a clear indication
A clinician may recommend supplementation for a documented deficiency or specific condition. That differs from routine use for everyone. Review product names and doses with the care team rather than replacing treatment with “free-radical fighting” claims.
Related reading: Do I need a multivitamin, or is a balanced diet enough?.