A lipid-protein particle that transports dietary FAT and fat-soluble vitamins to the liver, muscles, and fat tissue via the lymph and the bloodstream. Chylomicrons keep water-insoluble lipids suspended in body fluids, which are mainly water. In this sense they can be considered emulsifying agents. Normally chylomicrons disappear from the blood within a few hours after a meal, as the fat they carry is consumed.
Chylomicrons demonstrate a complex metabolic history. After cells lining the small intestine (intestinal mucosa) absorb fatty acids from fat digestion, they convert them back to fat before packaging them as chylomicrons, to be released into the lymph. The lymph carries chylomicrons into the bloodstream. When chylomicrons reach the capillaries, they encounter an enzyme that breaks down the fat molecules in chylomicrons to free fatty acids. Released fatty acids are quickly taken up by cells for energy or fat storage. The deflated chylomicron remnants carry vitamins and cholesterol to the liver for storage or processing.