Re
Retinaldehyde
Retinal · RetinaldehydeActive
Vitamin A intermediate one conversion step closer to retinoic acid than retinol. More potent, often less irritating.
What it does
Retinaldehyde sits between retinol and retinoic acid in the conversion chain — only one step away from the active form. Some studies suggest it works faster than retinol with a similar tolerance profile. Less common in mass-market products because it's harder to formulate stably.
The evidence, graded
strongNo topical retinoid is recommended in pregnancy. The class covers tretinoin, adapalene, tazarotene, trifarotene, retinol, retinaldehyde, retinyl palmitate and hydroxypinacolone retinoate. Direct human data exist mainly for tretinoin and adapalene. The caution extends to the rest as a class-effect. Data on accidental exposure reassure, but are not strong enough to recommend any retinoid here. Oral isotretinoin is a separate case, with an absolute contraindication.Kaplan 2015 · British Journal of Dermatology ↗
expert consensusFor cosmetic anti-aging purposes, retinoids are not recommended under 18. Teen skin is already producing high collagen and cell turnover, and retinoid use in young people is reserved for treating conditions like acne — not for prevention of aging.Motamedi 2021 · Journal of Cutaneous Medicine and Surgery ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
retinal
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