Vitamin C

Vitamin C, or ascorbic acid, is an essential water-soluble nutrient that the human body cannot synthesize on its own. It must be obtained through diet or supplementation.
Authorized health claims (EU Regulation 432/2012): vitamin C contributes to normal collagen formation to ensure normal skin function; vitamin C contributes to the protection of cells against oxidative stress. These claims are authorized when the daily intake provides at least 15% of the NRV.
It is documented in scientific literature for its antioxidant role and as a cofactor in many enzymatic reactions, notably in collagen formation. These properties are documented in numerous clinical studies.
In topical use (cosmetic), vitamin C is associated, according to available data, with protection against oxidative stress, support for mechanisms involved in maintaining skin structure, and regulation of melanogenesis for the visible reduction of pigment irregularities.
Compliance note: EFSA-authorized claims for vitamin C in nutrition relate to normal collagen formation and protection of cells against oxidative stress. Any specific communication must remain consistent with this framework.
In summary, vitamin C is one of the best-documented nutrients, associated with protection against oxidative stress and normal collagen formation for normal skin function.