Vitamin C

Vitamin C is an antioxidant molecule that neutralises free radicals and inhibits the enzyme tyrosinase, which means it protects existing skin structure while slowing melanin production. It supports collagen synthesis and helps reduce visible oxidative stress over time.

What it actually does

Vitamin C, in its various forms, donates electrons to unstable free radicals generated by UV exposure, pollution, and metabolic processes. This neutralisation prevents oxidative damage to lipids, proteins, and DNA in skin cells. It also interferes with tyrosinase, the enzyme that converts tyrosine into melanin precursors, which gradually reduces hyperpigmentation and uneven tone. Beyond that, ascorbic acid acts as a cofactor for prolyl and lysyl hydroxylases, enzymes essential for stabilising collagen's triple helix structure during synthesis. This means it supports the dermis in maintaining tensile strength and resilience.

Topical vitamin C also reduces transepidermal water loss by reinforcing the lipid barrier, though this effect is dose-dependent and sensitive to formulation pH. Stability is the recurring challenge: ascorbic acid oxidises readily in water and light, which is why derivatives like ascorbyl glucoside or tetrahexyldecyl ascorbate appear in many formulations. Each derivative trades some potency for shelf stability, and conversion efficiency in the skin varies.

The OVESSI point of view

We approach vitamin C through the lens of Korean layered care, where potency is built through consistent, gentle doses rather than single aggressive applications. A serum with five percent ascorbic acid applied daily over four weeks delivers more cumulative benefit than fifteen percent used sporadically. French editorial luxury informs our expectation: vitamin C should feel like silk, not sting. We favour stabilised derivatives in hydrating bases, often paired with niacinamide or peptides to address multiple pathways without irritation. Scandinavian restraint means we do not overload a formula. If vitamin C is present, it is there at a concentration that respects the skin's pH and barrier integrity. We think about morning application under SPF, where its antioxidant function is most relevant, and we design textures that layer invisibly under makeup or other treatments.

What to expect, and when

Days zero to seven: no visible change. The skin may feel slightly more hydrated if the formula contains humectants alongside the vitamin C. Days eight to fourteen: a subtle increase in surface radiance, not a glow, just less dullness. This is mild light reflection from improved hydration and a smoother stratum corneum. Days fifteen to twenty one: early signs of evening tone in areas of mild hyperpigmentation, though sunspots and deeper melasma require months, not weeks. Days twenty two to twenty eight: a plateau. Skin looks quietly brighter and more even, but dramatic shifts do not happen. Vitamin C will not erase deep lines, it will not tighten sagging skin, and it will not reverse years of sun damage in one month. It offers cumulative protection and modest improvement, which compounds with continued use.

How to layer it in your ritual

Vitamin C sits in the treat step, after cleansing and toning, before oils or occlusives. In the morning, apply it to clean, dry skin, wait thirty seconds for absorption, then follow with a moisturiser and broad-spectrum SPF. This sequence maximises its antioxidant benefit during daytime exposure. At night, vitamin C can layer under retinoids or peptides, though some people find this irritating. If using both, consider alternating nights or applying vitamin C in the morning and retinoids at night. For sensitive or dry skin, buffer with a hydrating toner first, then apply vitamin C, then seal with a richer cream. Oily skin can use vitamin C alone under a light gel moisturiser. Avoid layering with high-concentration AHAs or BHAs in the same step, as low pH can destabilise certain vitamin C derivatives. Patience and consistency matter more than concentration.

Where it lives on our shelf

Vitamin C appears across several OVESSI treatments, formulated for different skin needs and ritual moments. The Soft Reset : Retinol Alternative Serum combines a stabilised derivative with bakuchiol for gentle brightening and antioxidant support. The Renewal : Retinol-Alternative Moisturiser layers vitamin C into a nourishing base for overnight barrier repair. The Gaze : Retinol-Alternative Eye Serum delivers a low-dose, non-irritating form around the delicate eye area. For those addressing uneven tone more directly, The Polish : Resurfacing Kojic Exfoliator and The Tone : Kojic Dark Spot Face Cream pair vitamin C with kojic acid for targeted pigment modulation. Each formula respects the ingredient's chemistry and your skin's tolerance.

Common questions

Can I use vitamin C if my skin is sensitive? Yes, if you choose a stabilised derivative in a hydrating base and introduce it slowly, starting three times per week.

Does vitamin C replace sunscreen? No, it enhances your SPF by neutralising free radicals that penetrate sunscreen, but it does not block UV rays.

Why does my vitamin C serum turn orange? Oxidation from air, light, or water exposure degrades ascorbic acid into dehydroascorbic acid, which has reduced efficacy and should be replaced.