Iron metabolism and laboratory testing for iron status

Abstract

Under normal circumstances, 1-2 mg of iron enters and leaves the body each day. Iron is absorbed in the duodenum, as heme and non-heme iron (Fe+2). Due to its ability to participate in redox-reactions, iron possesses toxic properties. Therefore, iron is usually found coupled with proteins: with transferrin in the circulation, and ferritin within the cells. Due to the lack of physiological pathway for iron excretion, iron absorption matches iron losses through bleeding, sweat and sloughing of epithelial cells. Extracellular export of stored iron is regulated by hepcidin that reduces the levels of ferroportin 1, an iron transporter from the cell.

Keywords

• iron
• metabolism
• transferrin
• ferritin
• ferroportin
• laboratory testing