Iron Tests
Reviewed
Iron tests measure different substances in the blood to check iron levels in your body. Iron is a mineral needed for growth, development, and making hemoglobin. Tests include serum iron, transferrin, total iron-binding capacity (TIBC), and ferritin.
Preparation and collection
Your provider may ask you to fast (not eat or drink) for 12 hours before your test. The test is usually done in the morning.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- The amount of iron in your blood varies throughout the day and may be higher in the morning.
- Some medicines, including birth control pills and estrogen treatments, can affect iron levels.
- Iron levels may also be lower for women during their menstrual cycles.
- If your iron test results are not normal, it does not necessarily mean you have a medical condition that needs treatment.
What to do next
If your iron test results are not normal, talk to your health care provider. Most conditions that cause too little or too much iron can be treated with iron supplements (for low iron), changes to your diet, medicines, and/or other therapies. Your provider may order additional tests such as hemoglobin, hematocrit, complete blood count, or mean corpuscular volume.