10% Vitamin C & Calendula Barrier Boosting + Glow Serum

Niacinamide — Vitamin B3 — a broadly-tolerated all-rounder that strengthens the skin barrier, evens tone and helps regulate oil. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~5%. OTC cap 10%. Give it 8–12 weeks for tone. Suits all skin types. One of the best-tolerated actives there is — fine for every skin type, and especially handy for oil and uneven tone.

Ascorbic Acid — An antioxidant that brightens dullness and helps defend against daytime free-radical damage — a morning serum ingredient. The label states 10%. Works from ~10%. OTC cap 20%. Give it 8–12 weeks for dark spots. Best for Normal, Combination, Oily. A morning antioxidant that brightens. High-strength L-ascorbic acid at a low pH can sting sensitive skin — go for a gentler derivative. Mid-value: beats 70% of the 11 Ascorbic Acid serums that state their strength.

Sodium Hyaluronate — A humectant that holds water in the upper skin — pure hydration, tolerated by essentially everyone, at any concentration. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~1%. Works Ongoing while you use it; no weeks-long build-up to wait for. Suits all skin types. Pure hydration — suits everyone, and dry or dehydrated skin most of all. Apply on damp skin and seal it in.

Ceramide NP — The skin's own barrier lipids — they patch a compromised moisture barrier, which is why they pair so well with actives that resurface. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~1%. Works 1–3 weeks for a calmer, less reactive barrier. Best for Dry, Sensitive, Normal, Combination. The skin's own barrier lipids — ideal for dry, sensitive or compromised skin, and safe for anyone.

Cholesterol — The barrier's own lipid — repairs with ceramides and fatty acids. The strength is not printed, so we cannot judge the dose; that counts against the brand. Best for .

Betaine — A sugar-beet humectant — steady, gentle hydration for any skin. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~5%. OTC cap 5%. Best for .

Niacinamide: a review on dermal delivery strategies and clinical evidence ›

Niacinamide - mechanisms of action and its topical use in dermatology ›

Mechanistic Basis and Clinical Evidence for the Applications of Nicotinamide (Niacinamide) to Control Skin Aging and Pigmentation ›