Bilirubin is a reddish-yellow pigment found in bile that is produced by the breakdown of hemoglobin, a pigment in red blood cells. The liver removes bilirubin from the bloodstream and secretes it in the bile. Bile helps the body digest and absorb fatty foods. It also rids the body of certain waste products. Bilirubin gives bile its color, which ranges from brown to greenish-yellow. Bilirubin joins with fat-soluble chemicals in the liver to form a product that is secreted in the bile.
An excess of bilirubin in the blood can produce jaundice, a yellowish discoloration of the skin, the tissues, and the whites of the eyes. Jaundice is not a disease but a symptom of various diseases. For example, jaundice may result if diseased liver cells fail to remove bilirubin from the blood. It also may occur if gallstones block the common bile duct, preventing the secretion of bilirubin in the bile. However, jaundice does not always signal a liver disorder. Some cases result from an increased breakdown of red blood cells.
See also Liver .
