Skincare: actives, concentrations, and medical grade

Mon, 27 Apr 2026 00:00:00 +0000

Abstract. Almost all mass-market skincare is under-dosed, unstable, or poorly formulated. Almost all medical grade skincare costs more — but not always for the right reasons. Here I draw the line on what “active” really means in a cosmetic (concentration, pH, vehicle, penetration, stability), which pillars of the dermatological literature actually hold up (retinoids, vitamin C as L-ascorbic acid, niacinamide, azelaic acid, AHA/BHA), and which are the more recent fashions selling mostly stand-in ingredients: cosmetic peptides, bakuchiol as “natural retinol”, snail mucin, plant stem cells. And why — beyond a certain marketing premium — medical grade products often have technical reasons to cost more. Second part of a three-part series, after Aesthetic medicine: what works, what is marketing.

In the cosmetics aisle of a pharmacy or in the pages of a skincare e-commerce site, ingredients turn up everywhere. Vitamin C, retinol, peptides, hyaluronic acid, niacinamide, ceramides, plant oils, botanical extracts. The promise is always the same — younger, firmer, brighter, more protected skin — and the vocabulary is almost identical between an eight-euro serum and a hundred-and-twenty-euro cream.

There is a problem, and it is hard to fit on a label. A cosmetic works — when it does work — because it contains a sufficient amount of a molecule with proven efficacy, formulated so that it stays stable, and delivered so that it crosses the stratum corneum enough to do something. Almost the entire mass-market skincare industry trades on the perception of efficacy — pleasant texture, fragrance, bottle design, marketing claims — more than on actual efficacy. It is not a scam: it is a sector with an enormous grey area between “contains an active ingredient” and “does what it promises”.

Niacinamide on noema

Skincare: actives, concentrations, and medical grade