Sodium Lauryl Sulfate

SLS

CAUTION, It does NOT cause cancer, that viral claim is a myth. What it actually does is strip and irritate skin, which matters if yours is reactive.

What it is

An anionic surfactant used as a primary cleansing and foaming agent. Harsher than SLES; does not go through ethoxylation so does not carry a 1,4-dioxane contamination risk.

In this product: Primary cleansing and foaming surfactant.

Dose & route, what actually matters

Dermal contact, rinse-off. Brief exposure; primary concern is repeated disruption of the skin barrier, particularly in individuals with low ceramide baseline or pre-existing dermatitis.

EUROPEAN UNION

Not restricted under EU Cosmetics Regulation Annex II or III. No concentration limit for rinse-off products.

UNITED STATES

Permitted; no FDA restriction. No Prop 65 listing.

The evidence

1% and 3% SLS applied under occlusion in 14 human volunteers induced dose-related increases in transepidermal water loss (TEWL) and erythema, with inverse correlations between baseline ceramide levels and severity of irritant reaction.

human · 1996 · source

California Prop 65: Not listed.

How to avoid it

Look for shampoos marked 'SLS-free.' Alternatives include coco-glucoside, decyl glucoside, and sodium cocoyl isethionate.

Where it hides

Head & Shoulders Classic Clean →Pantene Pro-V Daily Moisture Renewal →Herbal Essences Hello Hydration →Colgate Total SF Clean Mint →Crest 3D White PRO Advanced Whitening →Tide Original Liquid Laundry Detergent →

Editorial analysis of publicly available regulatory and peer-reviewed sources. Not medical advice. We name our evidence and link it, including when an ingredient is fine.