Ammonium Laureth Sulfate vs Sodium Cocoyl Isethionate: which is worse?

What is Ammonium Laureth Sulfate?

Ammonium laureth sulfate is an anionic surfactant very similar in structure to SLES but uses an ammonium counterion instead of sodium. It produces abundant foam and provides excellent conditioning to the hair shaft during washing.

What is Sodium Cocoyl Isethionate?

Sodium cocoyl isethionate is a mild anionic surfactant derived from coconut fatty acids and isethionic acid. It exists as a solid powder and produces a creamy, conditioning lather that leaves skin feeling soft. It is the primary surfactant in most syndet (synthetic detergent) bars.

Documented risks

Ammonium Laureth Sulfate: Ammonium laureth sulfate shares a similar safety profile to SLES. The CIR has concluded it is safe for cosmetic use. Like SLES, it may contain trace 1,4-dioxane from ethoxylation, addressed by standard manufacturing controls. It is not a carcinogen or endocrine disruptor. Mild skin irritation is possible in sensitive individuals at high concentrations but is not a concern at typical use levels in rinse-off products.

Sodium Cocoyl Isethionate: Sodium cocoyl isethionate has an excellent safety record. It is one of the surfactants recommended by the National Eczema Association for sensitive and atopic skin. No carcinogenic, mutagenic, or endocrine-disrupting effects are known. Potential contact sensitization is extremely rare. It performs well at physiological pH, minimizing skin barrier disruption.