Antioxidant
Antioxidant — a molecule that neutralizes free radicals and reactive oxygen species, helping to limit oxidative stress in the skin. In skincare, antioxidants such as vitamin C, vitamin E, niacinamide, and ferulic acid are used to support the skin's defenses against environmental stressors like UV exposure and pollution.
Key points
- Antioxidants work by donating electrons to unstable free radicals, stopping the chain reactions that damage skin cells and collagen.
- Common topical antioxidants include vitamin C (ascorbic acid), vitamin E (tocopherol), niacinamide, ferulic acid, resveratrol, and green tea polyphenols.
- Antioxidants are often paired with sunscreen because they help address free radical damage that sunscreen alone does not fully prevent.
- Certain antioxidants can be unstable when exposed to light and air, so formulation and packaging influence how effective a product remains over time.
Frequently asked
Do antioxidants replace sunscreen?
No, antioxidants complement sunscreen rather than replace it; sunscreen blocks and absorbs UV radiation, while antioxidants help counter the free radical damage that still occurs.
Can I use more than one antioxidant at a time?
Yes, several antioxidants can be layered or combined, and some pairings such as vitamin C with vitamin E and ferulic acid are used together because they can support one another's stability and activity.
Related topics
This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.
