Digestion and absorption of other dietary lipids

The small intestine absorbs a variety of important lipids present in the diet or secreted in the bile using pathways similar to those for dietary triglycerides (Chap. 7). In this chapter, the mechanisms for absorption of cholesterol, phospholipid, bile acids, and the four fat-soluble vitamins will be reviewed. Absorption of these lipids will be considered with respect to intraluminal events, mechanisms for uptake across the brush-border membrane, metabolism within the enterocyte, and intracellular transport and secretion; the emphasis will be on the unique features of each lipid compound. In addition, the hepatic uptake and metabolism of the fatsoluble vitamins will be discussed.