Antioxidants are ingredients that neutralize reactive oxygen species and free radicals generated by UV exposure and environmental stressors, helping limit oxidative damage to skin cells and lipids. Common examples include vitamin C, vitamin E, ferulic acid, niacinamide, and polyphenols.
| Reported effect | How often | Notes |
|---|---|---|
| Mild irritation, stinging or redness | Uncommon | More likely with low-pH or high-concentration formulations such as L-ascorbic acid. |
| Dryness or peeling | Uncommon | Can occur when combined with other actives or in sensitive skin. |
| Allergic contact dermatitis | Rare | Reported with certain antioxidants like vitamin E (tocopherol) and some plant-derived polyphenols. |
| Paradoxical pro-oxidant effect | Rare | Some antioxidants may act as oxidants at high concentrations or when oxidized/degraded in formulation. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.