---
title: Lactic Acid
entity_type: Ingredient
canonical_url: https://skinknowledgebase.com/ingredients/lactic-acid
date_modified: 2026-05-15
date_reviewed: 2026-05-15
mcp_eligible: true
evidence_sources:
  - title: DermNet — Alpha hydroxy acid facial treatments
    canonical_citation_url: https://skinknowledgebase.com/sources/dermnet-alpha-hydroxy-acid-facial-treatments
    original_source_url: https://dermnetnz.org/topics/alpha-hydroxy-acid-facial-treatments
    source_type: other
  - title: Clinical and cosmeceutical uses of hydroxyacids
    canonical_citation_url: https://skinknowledgebase.com/sources/hydroxyacids-review-2009
    original_source_url: https://pubmed.ncbi.nlm.nih.gov/19695482/
    source_type: peer_reviewed
  - title: AAD — How to safely exfoliate at home
    canonical_citation_url: https://skinknowledgebase.com/sources/aad-safe-exfoliate-at-home
    original_source_url: https://www.aad.org/public/everyday-care/skin-care-secrets/routine/safely-exfoliate-at-home
    source_type: dermatology_reference
product_fact_sources: []
---

# Lactic Acid

## Quick Summary

Lactic Acid is an alpha hydroxy acid used in exfoliating skincare for dull-looking texture, roughness, and surface glow. It is water-soluble and is often described as a gentler-feeling AHA option than glycolic acid, though it can still sting or irritate if overused.

## What It Is

Lactic Acid is a named AHA, not just a generic exfoliant. It belongs with glycolic acid and mandelic acid in the alpha hydroxy acid family, but it deserves its own Ingredient page because consumers search for it separately and formulas position it differently.

## Mechanism

In cosmetic skincare, Lactic Acid is used for surface exfoliation. It helps smooth the look of dull, rough surface texture so the skin can look softer and more radiant over time.

## Related Entities

- [DermNet — Alpha hydroxy acid facial treatments](https://skinknowledgebase.com/sources/dermnet-alpha-hydroxy-acid-facial-treatments)
- [Clinical and cosmeceutical uses of hydroxyacids](https://skinknowledgebase.com/sources/hydroxyacids-review-2009)
- [AAD — How to safely exfoliate at home](https://skinknowledgebase.com/sources/aad-safe-exfoliate-at-home)
- [Dullness](https://skinknowledgebase.com/concerns/dullness)
- [The Ordinary Glycolic Acid 7% Exfoliating Toner](https://skinknowledgebase.com/products/the-ordinary-glycolic-acid-7-exfoliating-toner)
- [Over-exfoliation Irritation](https://skinknowledgebase.com/side-effects/over-exfoliation-irritation)