About LECITHIN: Lecithin is a naturally ocurring lipid found in both plants and animals. According to the PETA's Caring Consumer guide, lecithin for com mercial purposes is most commonly obtain from eggs and soybeans.
This ingredient may be derived from animals. From PETA's Caring Consumer: Waxy substance in nervous tissue of all living organisms. But frequently obtained for commercial purposes from eggs and soybeans. Also from nerve tissue, blood, milk, corn. Choline bitartrate, the basic constituent of lecithin, is in many animal and plant tissues and prepared synthetically. Lecithin can be in eye creams, lipsticks, liquid powders, hand creams, lotions, soaps, shampoos, other cosmetics, and some medicines. Alternatives: soybean lecithin, synthetics.
Reference：藥妝品學 Cosmeceuticals, 2nd edition
MF: C46H89NO8P+ MW: 815.2g/mol
In cosmetics and personal care products, lecithin functions as an emollient, an emulsifier, and as a penetration enhancer.
As an emollient, topically applied lecithin has the ability to soften and soothe the skin. Its high concentration of fatty acids creates a barrier on the skin that effectively seals moisture in while keeping air and other environmental elements out.