Oleic can be formed by body tissues. When the double bond furthest from the carboxyl group is three carbons from the methyl end, it belongs to the n-3 family. Phospholipids and cholesterol are absorbed in small amounts, mainly as the constituents of cell membranes and myelin sheaths. Cholesterol is not found in food of plant origin. The structure of lipids is characterised by the relative lack of oxygen.
Fats consist almost exclusively of carbon and hydrogen.
They are hydrophobic. TG can be converted to other lipids if required. Phospholipids and cholesterol have their principle function in the formation of all interior and exterior cell membranes. Biles acids - main route for cholesterol catabolism, though cholesterol is also used in producing the steroid hormones and Vit. EPA may depress cholesterol production by the liver and increase the number of LDL receptors.