Antioxidants neutralise the free radicals generated by UV and pollution before they damage collagen and DNA. They are best thought of as daytime defence that works alongside — not instead of — sunscreen. Some are potent and well-studied (ferulic, astaxanthin); others are promising but modest.
Their shared job is quenching reactive oxygen species. Ferulic acid is best known for stabilising and boosting a vitamin C + E serum — the classic daytime trio. Astaxanthin is an unusually potent carotenoid with encouraging data. Coenzyme Q10 and alpha-lipoic acid have modest evidence for texture and fine lines.
A few sit here for related reasons: caffeine and adenosine are antioxidants that also feature in eye products for puffiness and fine lines. As a group, antioxidants amplify your sun protection rather than replace it — the highest-value place for them is in your morning routine, under sunscreen.
Every antioxidant we cover, with what it does and the concerns it is most often used for. Each name links to its full glossary entry.
| Ingredient | What it is | Most used for |
|---|---|---|
| Ferulic Acid | A plant-derived antioxidant found in cell walls of grains and seeds. | Aging, Pigmentation |
| Astaxanthin | A xanthophyll carotenoid from microalgae — considered one of the most potent natural antioxidants known. | Aging, Redness |
| Coenzyme Q10 | A fat-soluble quinone essential for mitochondrial ATP production. | Aging |
| N-Acetyl Cysteine | A precursor to glutathione — the body's primary endogenous antioxidant. | Aging, Pigmentation, Redness |
| Glutathione | The body's most abundant endogenous antioxidant, produced in every cell. | Pigmentation, Aging |
| Caffeine | Topical caffeine works as a potent vasoconstrictor (reducing undereye puffiness and dark circles), a phosphodiesterase inhibitor (breaking down fat in adipocytes for cellulite applications), and an antioxidant protecting against UV-induced DNA damage. | Aging, Redness |
| Adenosine | A naturally occurring purine nucleoside with FDA-approval as an anti-wrinkle ingredient — one of only a handful of OTC actives with this designation. | Aging |
| Alpha Lipoic Acid | The "universal antioxidant" — unique in being both water- and fat-soluble, allowing it to work in all cell compartments. | Aging, Dullness |
| Ergothioneine | A sulphur-containing amino acid the body can't make — taken up from diet (mushrooms are the richest source) through a dedicated transporter, OCTN1, that concentrates it in tissues under oxidative stress. | Aging, Dullness |
Across the catalogue, the antioxidants here are most often used for these concerns — each links to its evidence-led concern hub with a full routine:
Aging (9), Pigmentation (3), Redness (3), Dullness (2).
These commonly pair well with: Vitamin E, Vitamin C, Ferulic Acid, N-Acetyl Cysteine, Matrixyl 3000, Hyaluronic Acid. Pairing is about getting more from a routine without adding irritation — humectants, barrier lipids and niacinamide are frequent partners here.
Nothing in this category carries a hard "avoid combining" flag in our catalogue — these are generally cooperative actives. Always introduce one new product at a time regardless.
They neutralise free radicals — unstable molecules produced by UV light and pollution that break down collagen and accelerate aging. Applied in the morning, topical antioxidants add a layer of daytime defence that helps protect the results of sunscreen and every other active. They reduce damage; they do not reverse it.
Morning is where antioxidants earn their keep, because that is when your skin faces UV and pollution. A vitamin C, ferulic and vitamin E serum under sunscreen is the classic daytime setup. Using them at night is not harmful, just less strategically useful.
Yes — it is one of the best-evidenced antioxidant pairings. Ferulic acid stabilises vitamin C and vitamin E and boosts their photoprotective effect, which is why the vitamin C + E + ferulic serum became a reference formula. The combination is more effective and more stable than vitamin C alone.
No. Antioxidants reduce the free-radical damage that gets through, but they do not block UV the way sunscreen does. They are a complement, not a substitute — the two work together, and sunscreen remains the non-negotiable base of any daytime routine.
Browse the rest of the ingredient library: Acids, Retinoids, Vitamins — or see the full ingredient categories index.
Written and reviewed by JoAnn, editor of Skin Stacker — see our methodology and editorial standards.
Reviewed / last updated: 2026-07-17. For informational purposes only — not a substitute for medical advice.