Total iron-binding capacity (TIBC) is a blood test that measures the amount of iron that can potentially be stored in blood.

The test is done to help diagnose known or suspected iron deficiency. It can also provide information about a person's nutritional status. TIBC can help tell the difference between certain types of anemia that require different treatment.

Iron in the blood is vital to life. Iron in red blood cells helps to carry oxygen in the body. The body's iron comes from food. Iron is transported in the blood attached to a molecule called transferrin. The TIBC test measures the maximum amount of iron that can be attached to transferrin.

Who is a candidate for the test?

A healthcare provider usually orders this test when he or she suspects anemia, which is a low red blood cell count. This test may also be used to try to determine the type of anemia present.

How is the test performed?

In order to measure the TIBC, a blood sample is needed. The blood is usually taken from a vein in the forearm or hand. The blood is then sent to the laboratory for testing.