Bile is a bitter fluid, yellow, brown or green in color, that is comprised of water, electrolytes, and organic molecules, including bile acids, cholesterol, phospholipids and bilirubin. Present in many species, bile has two main functions. First, the bile acids it contains are critical for digestion and for the absorption of fats and fat-soluble vitamins in the small intestine. Second, many of the body's waste products are secreted into the bile and are then eliminated in the fecal material. Bile ducts and the biliary system participate in these functions.

Humans normally produce 400-800 ml of bile daily. If this production or the flow of bile from the liver to the small intestine is impeded, a condition called jaundice can result.

Bile is produced in hepatocytes, which are the main functional cells of the liver. The bile...