triglyceriidid

Triglycerides are a class of lipids formed by the esterification of glycerol with three fatty acid molecules. This triester structure makes triglycerides the main storage form of fatty energy in both animals and plants. In the body, triglycerides are stored in adipose tissue as lipid droplets; in foods they occur as fats and oils depending on temperature and fatty acid composition.

The fatty acids attached determine properties: saturated (no double bonds), monounsaturated (one double bond) and polyunsaturated (two or more). Saturated triglycerides tend to be solid at room temperature; unsaturated triglycerides are usually liquid (oils). Common fatty acids include palmitic, stearic, oleic, linoleic and linolenic acids. The chain length and degree of unsaturation influence melting point and fluidity. Triglycerides occur in many dietary fats, such as butter, lard and various plant oils.

Digestive lipases hydrolyze triglycerides to glycerol and free fatty acids; these are taken up by cells and fatty acids undergo beta-oxidation to produce ATP. Glycerol can enter gluconeogenesis or glycolysis in the liver.

Blood triglyceride levels reflect dietary fat intake and metabolic state; elevated triglycerides are a risk factor for cardiovascular disease, particularly with other risk factors. Management includes weight reduction, physical activity and, when needed, medication.

In summary, triglycerides are the principal energy-storage lipids in biology, formed by glycerol and three fatty acids, with properties that depend on fatty acid composition and chain length.