Sodium Lauroyl Methyl Isethionate

Sodium Lauroyl Methyl Isethionate is a mild anionic surfactant commonly used in cleansers and syndet bars (often several percent up to higher levels in solid bars) and is generally less irritating than sulfates in patch/usage testing. However, as a detergent it can still disrupt barrier lipids and provoke stinging or eczema flares in compromised or highly reactive skin, especially with frequent cleansing or in multi-active routines. Given its overall good tolerability but non-zero risk inherent to surfactants, a gentle (not exceptionally gentle) score is most consistent with patient-safety benchmarks. Safety Notes: In commercial rinse-off facial/body cleansers and shampoo/conditioning shampoo systems, Sodium Lauroyl Methyl Isethionate is often used at low levels (~0.5–2%) as a mildness/foam booster alongside other surfactants, while mainstream sulfate-free cleansers commonly sit around ~3–12%. The highest consumer-available levels are found in syndet bars and high-solids cleanser concentrates where total isethionate surfactant actives can be very high; finished products can reach ~15–30% SLMIs depending on whether the raw material is supplied as neat flakes or diluted noodles. It is rarely used in leave-on products except at trace/very low levels due to its primary function as an anionic rinse-off surfactant.