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
strongAll topical retinoids — tretinoin, adapalene, retinol, retinaldehyde, retinyl palmitate, and hydroxypinacolone retinoate — are not recommended during pregnancy. Direct human data exist mainly for the prescription retinoids (tretinoin, adapalene); the caution extends to the others as a precautionary class-effect. Data on inadvertent exposure reassure but aren't strong enough to recommend any retinoid in pregnancy.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
Pairs worth knowing
This page is public and indexed on purpose (unlike profiles and drops, which are unlisted) — it’s the citation behind shared ingredient cards, and it should be findable.
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