Cholesteryl esters derived from cholesterol, are dietary lipids. They form when enzymes in the human body metabolize cholesterol with an ester bond between the carboxyl group of fatty acids and the hydroxyl group of cholesterol. Cholesteryl esters are extensively found in animal body fluids (plasma lipoproteins) and can also appear as fatty streaks in blood vessel walls, contributing to atherosclerosis. Their strong hydrophobic nature results in low solubility in water.