Lactic Acid

Introduction

What is lactic acid?

Lactic acid is a mild alpha-hydroxy acid formed through fermentation by lactic acid bacteria. It is found in many foodstuffs, such as sour milk and tomato juice (R). In animals, it is constantly produced during metabolism and exercise (R).

Does lactic acid get absorbed?

The skin permeation of lactic acid depends on its concentration and the pH of the vehicle. In one study using gel formulations, the permeation increased as the concentration of lactic acid rose, and decreased as the pH of gels was increased. The greatest permeation was obtained with a concentration of 9% and a pH of 2.8 (R).

Efficacy

Show 4 more outcomes
Outcome	Grade	Effect	Evidence	Studies
Skin Thickness	B	🠩🠩 Notable	★★★ Fair	3 studies 11 participants
Skin Brightness	B	🠩 Slight	★★★ Fair	2 studies 57 participants
Skin Barrier Function	B	🠩 Slight	★★★ Fair	2 studies 11 participants
Skin Smoothness	B	🠩 Slight	★★★ Fair	1 study 46 participants
Hyperpigmentation	B	🠫 Slight	★★★ Fair	1 study 46 participants
Wrinkles	C	⇩ Potential	★★★ Fair	2 studies 52 participants
Skin Firmness	C	⇧ Potential	★★★ Fair	2 studies 52 participants
Skin Hydration	C	⇧ Potential	★★ Some	2 studies
Fine Lines	E	– No Effect	★★★ Fair	1 study 46 participants

Mechanisms

Outcome	Grade	Effect	Evidence	Studies
Skin Cell Renewal	C	⇧ Potential	★★ Some	1 study 8 participants
Glycosaminoglycans	C	⇧ Potential	★★ Some	1 study 5 participants
Collagen	E	– No Effect	★★ Some	1 study 5 participants
Elastic Fibres	E	– No Effect	★★ Some	1 study 5 participants
Inflammation	E	– No Effect	★★ Some	1 study

Side Effects

Outcome			Effect		Frequency			Studies
Skin Redness			⇧ Increase		—			2 studies

Latest Research

What is lactic acid?

Does lactic acid get absorbed?

Superior Efficacy of an Herbal-based Cosmeceutical Compared With Common Prescription and Cosmetic Antiaging Therapies (2016)

A double-blind, randomized clinical trial of 20% alpha/poly hydroxy acid cream to reduce scaling of lesions associated with moderate, chronic plaque psoriasis (2013)

Clinical and cosmeceutical uses of hydroxyacids (2009)

The effects of topical alpha-hydroxyacids on the normal skin barrier of hairless mice (2001)

Alpha hydroxyacids modulate stratum corneum barrier function (1997)