Substance typically found in plant and animal lipids (fat). Fatty acids include compounds such as glycerides, sterols, and phospholipids. They are used in cosmetics as emollients, texture enhancers, and, when mixed with glycerin, cleansing agents.
References for this information:
Free Radical Research, April 2002, pages 471–477
Journal of Lipid Research, May 2002, pages 794–804
natural moisturizing factor (NMF)