The ingredient, explained

Lactic Acid

An exfoliating acid with human research on a specific L-lactic acid cream for photodamaged skin.

HumectantAHA exfoliantBufferingSkin conditioning

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Ingredient guide

What it is and what it does

Propanoic acid, 2-hydroxy-

About this ingredient: EU CosIng ingredient registry (via Open Beauty Facts taxonomy) ↗

Humectant: Helps attract and retain moisture.
AHA exfoliant: Alpha hydroxy acid category. Exfoliation depends on the acid, concentration, pH and the rest of the formula; an AHA may also be used to control pH.
Buffering: Helps resist changes in a formula's pH.
Skin conditioning: A broad cosmetic role for maintaining skin condition. It does not identify a particular clinical benefit.

Function definitions: European Commission ingredient function definitions (SCCNFP/0299/00, pages 16 to 20) ↗ · FDA: Alpha hydroxy acids ↗

Registry functions describe possible formulation roles, not results for a finished product. A dictionary entry is not an approval or a safety assessment.

A closer look

What the research shows

Human topical research

A 22-week, randomised, vehicle-controlled trial enrolled 74 women aged 40 to 70 and compared 8% L-lactic acid cream, 8% glycolic acid cream and their vehicle. The lactic acid group had modest improvements in overall facial photodamage, with some additional forearm improvements.

What this does not tell us

The paper tested the L form at 8% in a particular cream. A label does not disclose its acid form, free-acid level or pH. These results do not apply to injectable poly-L-lactic acid, which is a different material and route.

Sources for this summary. PubMed 8651713 ↗

Research review checked Sep 30, 2026

Selected primary sources were reviewed for the existing research brief on 30 September 2026, with exact ingredient, route and combination limitations recorded. This was a bounded editorial review, not a systematic search.