Ferritin is one the proteins available in the body that stores the iron and releases it whenever needed. It is found in the liver, immune system, and the body cells. It consists almost 20% of the iron that is present in our blood. Ferritin binds with the transferrin to make the new blood cells and hence the iron stored plays a vital role in making the new RBCs. When a person is suffering from the symptoms that are related to the low and high level of iron in the body, then ferritin blood test is suggested by the doctor. Based on how much amount of ferritin is available the treatment is started by the doctors.