Phosphatidylcholine is the most abundant phospholipid in eukaryotic cell membranes and a primary constituent of lecithin derived from soy or sunflower. It features a glycerol backbone with two fatty acyl chains and a phosphocholine polar head, conferring amphiphilic properties essential for forming bilayers and micelles. Widely used as an emulsifier in food processing, it stabilizes emulsions in chocolate, margarine, and baked goods. In biochemistry, it participates in lipid signaling, lipoprotein assembly, and choline donation for acetylcholine synthesis. Dietary supplements containing phosphatidylcholine support liver function and may aid in managing non-alcoholic fatty liver disease based on clinical studies. It is generally recognized as safe (GRAS) by regulatory bodies for food applications.