Lithocholic acid (LCA) is a hydrophobic secondary bile acid that is primarily formed in the intestine by the bacterial 7-α dehydroxylation of chenodeoxycholic acid. Acts as a detergent to solubilize fats for absorption. Known to display both carcinogenic and apoptotic activities. Also binds to the p53 binding sites of both MDM2 and MDM4 with a five-fold preference for MDM4.