Definition: When red blood cells become old or damaged, they are broken down in the body, resulting in a yellow pigmented chemical called bilirubin. Under healthy circumstances, red blood cells are broken down by the spleen, and through a series of chemical steps in the spleen and liver, eventually become bile.
If the liver is damaged, it isn't able to use the bilirubin produced by the spleen. Too much bilirubin in the blood is called hyperbilirubinemia and can lead to jaundice. As bilirubin collects in the blood, some bilirubin leaks into nearby tissues, giving a yellow tint to the skin and whites of the eyes.
