Last verified: 20 days ago
Sodium Lauryl Sulfate
Also known as: SLS, sodium dodecyl sulfate, SDS, lauryl sulfate sodium salt
Evidence under review. — Not yet rated
Industrial surfactant used in labs to damage skin and test products — not a supplement ingredient.
-
What it does
Sodium Lauryl Sulfate (SLS) is a synthetic detergent and surfactant found in cleaning products, toothpastes, and shampoos. In research, it is primarily used as a controlled irritant to...
-
Evidence quality
Evidence base hasn't been formally rated yet. See research below.
-
Clinical dose
No established dose as a supplement ingredient
-
Found in
What the Science Says
Sodium Lauryl Sulfate (SLS) is a synthetic detergent and surfactant found in cleaning products, toothpastes, and shampoos. In research, it is primarily used as a controlled irritant to deliberately damage the skin barrier in lab models, allowing scientists to test whether moisturizers and skin-repair products actually work. It also appears in pharmaceutical manufacturing as a wetting agent to help poorly soluble drugs dissolve faster. Despite appearing in over 1,000 registered supplement products in the NIH database, this is almost certainly as an inactive excipient (a processing aid), not as an active ingredient with health benefits.
What It Doesn't Do
SLS has no known health benefits when consumed or applied to skin. It does not repair skin — it is literally used in studies to break skin barriers down. It is not an anti-inflammatory, antioxidant, or therapeutic agent for humans. It does not treat eczema, improve gut health, or support any supplement marketing claim. Lab studies showing antimicrobial activity used concentrations far too high to be safe or practical in any supplement context.
Evidence-Based Benefits
Sodium Lauryl Sulfate (SLS) is a synthetic detergent and surfactant found in cleaning products, toothpastes, and shampoos. In research, it is primarily used as a controlled irritant to deliberately damage the skin barrier in lab models, allowing scientists to test whether moisturizers and skin-repair products actually work. It also appears in pharmaceutical manufacturing as a wetting agent to help poorly soluble drugs dissolve faster. Despite appearing in over 1,000 registered supplement products in the NIH database, this is almost certainly as an inactive excipient (a processing aid), not as an active ingredient with health benefits.
Weak EvidenceEffective at: No established dose as a supplement ingredient
Source: auto-research
Absorption & Bioavailability
Unknown for oral supplementation — no human pharmacokinetic data provided in the studies. As a surfactant, it is a known skin penetration enhancer, which raises absorption concerns rather than benefits.
Red Flags to Watch For
- SLS is used in research specifically to DAMAGE skin barriers — its presence as an 'active' supplement ingredient is a major red flag
- Aquatic toxicology data shows SLS causes organ damage, oxidative stress, and immune disruption in animals at low concentrations (4 mg/L)
- No clinical trials in the provided data test SLS as a beneficial supplement ingredient for humans
- Appearing in 1,000+ supplement products almost certainly means it is an inactive excipient (binder/wetting agent), not an active ingredient — but labeling it as an ingredient can mislead consumers
- Patch testing data shows 22.4% of people react positively to 0.25% SLS, indicating significant irritation potential even at low concentrations
Products Containing Sodium Lauryl Sulfate
See how Sodium Lauryl Sulfate is used in these analyzed products:
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-05-01