This test measures the amount of zinc in blood. Zinc is one of the essential minerals which is needed for the body's defense (immune) system to properly work. It plays a role in cell division, cell growth, wound healing and the breakdown of carbohydrates. Zinc is also an essential component of around 200 enzymes that are involved in a range of actions within the body and is needed for the senses of smell and taste too. Zinc depletion occurs in burn patients who lose zinc in the exudates from their burn sites. Hepatic cirrhosis causes excess loss of zinc by enhancing renal excretion. Other diseases that cause low serum zinc are ulcerative colitis, Crohn's disease, regional enteritis, sprue, intestinal bypass, neoplastic disease, and increased catabolism induced by anabolic steroids. The conditions of anorexia and starvation also result in low zinc levels.