Test Details: This test is useful for screening of chronic iron overload diseases, particularly hereditary hemochromatosis and iron deficiency anemia. Ingested iron is absorbed primarily from the intestinal tract and is temporarily stored in the mucosal cells as ferritin. Transferrin is the primary plasma iron transport protein, which binds iron strongly at physiological pH. Transferrin is generally only 25% to 30% saturated with iron. The additional amount of iron that can be bound is the unsaturated iron-binding capacity (UIBC). The total iron-binding capacity (TIBC) can be indirectly determined using the sum of the serum iron and UIBC.