Ferritin is a protein found inside cells that stores iron so your body can use it later. A ferritin test indirectly measures the amount of iron in your blood. The amount of ferritin in your blood (serum ferritin level) is directly related to the amount of iron stored in your body.
Iron Binding Capacity
Total iron binding capacity (TIBC) is a blood test to see if you may have too much or too little iron in the blood. Iron moves through the blood attached to a protein called transferrin. This test helps your doctor know how well that protein can carry iron in the blood.
Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries oxygen from our lungs throughout our bodies. It helps our muscles store and use oxygen. Iron is also part of many other proteins and enzymes.
Your body needs the right amount of iron. If you have too little iron, you may develop iron deficiency anemia. Causes of low iron levels include blood loss, poor diet, or an inability to absorb enough iron from foods. People at higher risk of having too little iron are young children and women who are pregnant or have periods.