Ferritin is a protein found in the body that stores iron and releases it when the body needs it. A Ferritin test measures the amount of this protein in the blood, which can help diagnose conditions related to iron levels. The test is commonly used to evaluate patients with symptoms of iron deficiency or iron overload, such as fatigue, weakness, and abnormal bruising. A high Ferritin level may indicate an excess of iron in the body, which can lead to conditions such as hemochromatosis or liver disease. Conversely, a low Ferritin level may suggest an iron deficiency, which can lead to anemia or other health problems. The Ferritin test is a simple blood test and is often performed as part of a routine blood panel.