Phospholipids

Phospholipids (e.g., lecithin-derived) are barrier-supportive emulsifiers/liposome-formers typically used at low to moderate concentrations (~0.1–5%) and are generally well-tolerated, including in sensitive-skin formulations. Clinical experience and patch-test data suggest low inherent irritancy, but because commercial phospholipid sources (soy/egg/sunflower) can carry trace impurities and rare allergenicity, a small risk of reactivity remains, warranting a very gentle (not inert) score. Safety Notes: In commercial skincare, phospholipids are often used at very low levels (~0.05–0.5%) as emulsifier co-surfactants, skin-conditioning lipids, or as part of liposome/encapsulation systems where the INCI appears but the active payload is small. Many leave-on barrier serums/creams and “lamellar” moisturizers use ~1–5% phospholipids (often via hydrogenated lecithin or phosphatidylcholine-rich blends) to build liquid-crystal structures and improve skin feel. High-strength OTC specialty products (liposomal bases, phosphatidylcholine concentrates, and some massage/oil-gel or ampoule-style formulas marketed for barrier repair) can reach ~10–20% total phospholipids, with higher levels being uncommon due to viscosity/texture limits, oxidation control needs, and cost; rinse-off formats typically sit at the lower end because of wash-off and surfactant system constraints.