The gentler AHA — exfoliates like glycolic while actually improving hydration.
A larger AHA molecule that penetrates more slowly (hence gentler), lactic acid exfoliates dead surface cells and doubles as a humectant — it's a component of the skin's own natural moisturizing factor. At 12% it has shown effects reaching into the dermis.
Studied at 5–12%; the firmness data comes from 12%.
12% improved firmness and fine wrinkling in controlled testing
A controlled trial of 12% lactic acid found increased skin firmness and thickness and reduced fine wrinkling versus vehicle. Lower concentrations mainly smooth and hydrate the surface.
Exfoliant and moisturizer in one — well documented
As part of the skin's natural moisturizing factor, lactic acid reliably improves hydration and rough, flaky texture in controlled studies — the reason it anchors so many body lotions for rough skin.
Anchored to regulatory assessments — not hazard lists. Dose makes the poison; these are the conclusions at real-world cosmetic use.
Same CIR conclusion as other AHAs: safe at ≤10% for consumers at pH ≥3.5 (12% products sit at the boundary — expect tingling). Increases sun sensitivity; use sunscreen.
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