Sodium Stearoyl Lactylate

Sodium stearoyl lactylate is an emulsifier/surfactant typically used at low concentrations (about 0.1–2%) to stabilize formulations and improve skin feel. Available safety and patch-test data generally show low irritation and low sensitization potential, though as a surfactant-type ingredient it can occasionally sting or irritate very compromised barriers (e.g., active eczema or post-procedure skin). Given its usual low use level and overall good tolerability but non-zero risk in highly reactive patients, it fits a "very gentle" score. Safety Notes: In consumer skincare, sodium stearoyl lactylate is most often used as a co-emulsifier/lamellar structurant at low levels (~0.05–0.3%) in light lotions, facial moisturizers, and cleansers where it supports stability and skin feel without materially impacting viscosity. Mainstream leave-on creams and body lotions commonly sit around ~0.5–2% as part of the primary emulsifier system. The upper end (~3–6%) is seen in high-structure, wax-free or “barrier/repair” style creams and some solid/anhydrous-to-water systems where formulators push lamellar gel network formation and stability; higher levels are limited by tack/soaping and sensory constraints rather than specific cosmetic regulatory caps.