CosmeticBet
Vitamins

Vitamin C

INCI: ASCORBIC ACID · also Vitamin C, L-ascorbic acid

An antioxidant vitamin that is hard to keep stable.

drag to turn
C6H8O6176.12 g/mol
oxygencarbonhydrogen
3D shape from PubChem 54670067

How common

All products1.5%
In hair colours39%
In face moisturisers4.3%
In conditioners1.3%

222 of 14,784 products with a full ingredient list in Open Beauty Facts; No. 184 of all the names found on their labels.

What it is

  • Vitamin C: a water-soluble vitamin and antioxidant, found in citrus fruits and many vegetables.

    3 sourcesHide
    Ascorbic Acid is a natural water-soluble vitamin (Vitamin C).[1] PubChem (US National Library of Medicine) · open source
    It is found naturally in citrus fruits and many vegetables.[1] PubChem (US National Library of Medicine) · open source
    Vitamin C is considered an antioxidant.[1] PubChem (US National Library of Medicine) · open source

Why it is in products

  • As an antioxidant against signs of sun ageing, and against dark spots.

    SourceHide
    Vitamin C is a potent antioxidant drug that can be used topically in dermatology to treat and prevent changes associated with photoageing. It can also be used for the treatment of hyperpigmentation.[2] Study · 2013 · open source

What it does

  • How much vitamin C in a cream helps is poorly understood. Skin holds a lot of it naturally, for making collagen and for protection against UV damage, but a review found the benefit of applying it unclear.

    Weak evidenceskin2 sourcesHide
    Normal skin contains high concentrations of vitamin C, which supports important and well-known functions, stimulating collagen synthesis and assisting in antioxidant protection against UV-induced photodamage.[3] Review · 2017 · open source
    the efficacy of such treatment, as opposed to optimising dietary vitamin C intake, is poorly understood[3] Review · 2017 · open source

Downsides and safety

  • It is unstable, and hard to deliver into the deeper skin in the right dose; research looks for more stable forms.

    Some evidenceSourceHide
    Because it is unstable and difficult to deliver into the dermis in the optimum dosage, research is being directed to find stable compounds of Vitamin C[2] Study · 2013 · open source

Where it works

SurfaceOuter layer(stratum corneum)Living layer(epidermis)Dermis

Meant to reach the deeper skin (the dermis), which is hard to do in the right dose.

Some evidenceSourceHide
difficult to deliver into the dermis in the optimum dosage[2] Study · 2013 · open source

Rules

European Union

  • No EU limit: it is not on the regulation’s lists of banned or restricted substances, preservatives or UV filters.

    How we checkedHide
    We searched Annexes II to VI of the EU regulation (consolidated text of 18 May 2026): no entry.open the list

United States

  • Not on the FDA’s list of prohibited or restricted cosmetic ingredients. In the US, cosmetics and their ingredients (other than colour additives) don’t need FDA approval before sale.

    SourceHide
    Under U.S. law, cosmetic products and ingredients, other than color additives, do not need FDA approval before they go on the market[4] US Food and Drug Administration · open source
    We searched the FDA’s list of prohibited and restricted cosmetic ingredients: no entry.open the list

Sources

  1. PubChem: Ascorbic acid (CID 54670067), record description PubChem (US National Library of Medicine)PubChem (US National Library of Medicine)
  2. Vitamin C in dermatology Telang PS, Indian dermatology online journal, 2013Study
  3. The Roles of Vitamin C in Skin Health Pullar JM et al., Nutrients, 2017Review
  4. Prohibited & Restricted Ingredients in Cosmetics | FDA US Food and Drug Administration

Checked against these sources on 4 November 2026. Spot a mistake? Tell us.