Ferritin is a globular protein complex consisting of 24 protein subunits and is the primary intracellular iron-storage protein, keeping iron in a soluble and non-toxic form. Ferritin is a ubiquitous intracellular protein that stores iron and releases it in a controlled fashion. In humans, it acts as a buffer against iron deficiency and iron overload. Ferritin is found in most tissues as a cytosolic protein, but small amounts are secreted into the serum where it functions as an iron carrier. Plasma ferritin is also an indirect marker of the total amount of iron stored in the body, hence serum ferritin is used as a diagnostic test for iron deficiency anemia.
Intestinal conditions that cause poor absorption of iron
Long-term digestive tract bleeding
Higher-than-normal levels may be due to:
Alcoholic liver disease
Hemochromatosis
Changes of Ferritin levels in time courses of patients with iron deficiency anemia in Alcoholic liver disease show earlier and consistently better improvement of Hb (dashed line) and iron (solid line) status. (*P <.001 and **P <.015 for changes vs baseline).