Ferritin is an iron storage protein that plays a central role in iron metabolism, and may be elevated in inflammatory or malignant diseases. It has been used in studies as an indicator of body iron supply, but may prove inaccurate in in the presence of chronic inflammation.

A ubiquitous iron storage protein that plays a key role in iron metabolism. It serves as an intracellular iron reserve (particularly in spleen, liver, intestinal mucosa, and bone marrow) and functions in iron detoxification. Studies have shown that ferritin iron incorporation is mediated by a ferroxidase activity associated with ferritin H subunits and a nucleation center associated with ferritin L subunits. Release of iron from ferritin has an essential role in iron-dependent lipid peroxidation and may contribute to free radical-induced cell damage in vivo. Therefore, by binding iron, ferritin may function as an antioxidant.