The ferritin test measures the level of ferritin in the body. Ferritin is a protein in the body that binds to iron; most of the iron stored in the body is bound to ferritin. Ferritin is found in the liver , spleen , skeletal muscles, and bone marrow. Only a small amount of ferritin is found in the blood. The amount of ferritin in the blood shows how much iron is stored in your body.The ferritin test is ordered to assess a person's iron stores in the body. The test is sometimes ordered along with an iron test and a TIBC to detect the presence and severity of iron deficiency or iron overload. Low levels of ferritin are indicative of iron deficiency, which causes anemia. High levels of ferritin can indicate an iron storage disorder, such as hemochromatosis, or It could also point to liver disease, rheumatoid arthritis, other inflammatory conditions or hyperthyroidism.