Sodium Lauroyl Sarcosinate vs Sodium Lauryl Sulfate: which is worse?

What is Sodium Lauroyl Sarcosinate?

Sodium lauroyl sarcosinate is an anionic surfactant derived from sarcosine (an amino acid derivative) and lauric acid from coconut oil. It is an acyl amino acid surfactant known for mildness and a smooth, silky after-feel.

What is Sodium Lauryl Sulfate?

Sodium lauryl sulfate is an anionic surfactant derived from lauryl alcohol (from coconut or palm oil). It is one of the oldest and most-studied cosmetic surfactants, prized for its powerful foaming and degreasing properties. Unlike SLES, it is not ethoxylated.

Documented risks

Sodium Lauroyl Sarcosinate: Sodium lauroyl sarcosinate is considered safe for cosmetic use by the CIR. It is non-irritating at typical use concentrations and has no known carcinogenic, mutagenic, or endocrine-disrupting properties. It can potentially form N-nitrosamines if formulated with nitrosating agents; good manufacturing practice prevents this. It is one of the preferred alternatives to SLS in dental formulations.

Sodium Lauryl Sulfate: SLS is safe at cosmetic use concentrations per the CIR Expert Panel. It is more irritating than SLES to skin and mucous membranes, particularly at concentrations above 2% with prolonged contact; this is why most rinse-off products keep it at 1–2% or opt for SLES. It can disrupt the skin barrier transiently, which is why some people with canker sores or eczema avoid SLS toothpastes and cleansers. It is not carcinogenic, not a hormone disruptor, and is not absorbed systemically in meaningful amounts. It biodegrades rapidly in the environment.