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Limited evidenceJoints & skin

Ferulic Acid

A plant antioxidant used mainly to stabilise vitamin C and E in topical serums. The skin evidence is for the combination applied to the face; taken as a capsule it has essentially no human data.

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What the science says

  • Topical antioxidant serums Limited evidence

    A randomized, investigator-blinded, split-face trial found that a vitamin C, E and ferulic acid serum improved photoaging outcomes after fractional laser treatment. The trial tested a three-ingredient serum, so it cannot show what ferulic acid contributes by itself.

  • Overall skin evidence Limited evidence

    A systematic review of ferulic acid for skin applications concluded that most studies are small, use combination formulations and vary widely in design and outcome measures. Its best-documented role is chemical: stabilising vitamin C and extending its shelf life in a serum.

  • Oral supplementation Limited evidence

    No randomized trial of oral ferulic acid for skin ageing, photoprotection or joint symptoms is indexed in PubMed. Oral bioavailability is low and ferulic acid is rapidly conjugated and excreted.

Dosage & safety

Studied doseTopical serums use 0.5–1% ferulic acid combined with 10–15% vitamin C and 0.5–1% vitamin E, applied once daily in the morning. No oral dose has been established.
SafetyTopical use is generally well tolerated; mild stinging or irritation can occur, especially in acidic vitamin C formulations. Oral safety in humans has not been formally studied. Not studied in pregnancy or breastfeeding.

How to take it

TimingApply in the morning to clean dry skin, before sunscreen, since the point is daytime photoprotection.
With food?Not taken by mouth — this is a topical ingredient and no oral dose has been established.
Worth knowingThrow the serum out when it turns dark orange or brown: that colour is the vitamin C oxidising, and ferulic acid only slows it, it does not stop it.

Interactions

With other supplements

  • topical vitamin C and vitamin E

    Ferulic acid stabilises L-ascorbic acid against oxidation and the three together give more photoprotection than any alone. use a serum that combines them in one formula rather than layering separate products

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does ferulic acid serum work for skin?

Ferulic acid has limited evidence on its own: a split-face trial found a vitamin C, E and ferulic acid serum improved photoaging after laser treatment, but the three-ingredient design cannot isolate ferulic acid. Ferulic acid's best-documented role is stabilising vitamin C in a serum.

Should I take ferulic acid supplements?

No randomised trial of oral ferulic acid for skin ageing, photoprotection or joints exists, and oral ferulic acid is poorly absorbed and rapidly excreted. No oral dose of ferulic acid has been established.

How do I use a ferulic acid serum?

Serums use 0.5–1% ferulic acid with 10–15% vitamin C and 0.5–1% vitamin E, applied once daily in the morning to clean, dry skin before sunscreen. A combined ferulic acid serum is better than layering separate products.

When should I throw out a vitamin C ferulic acid serum?

Throw out a ferulic acid serum when it turns dark orange or brown, because that colour is the vitamin C oxidising. Ferulic acid only slows the oxidation; it does not stop it.

Scientific references

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