What is an iron test?
An iron blood test checks the level of iron in your blood. Iron is a mineral that is absorbed into the body through foods such as spinach, red meats, fortified cereals, or seafood. Iron helps your body make red blood cells which carry oxygen from your lungs to the rest of the body. Iron also helps maintain muscle, bone marrow health, and organ function.
Several tests measure iron levels in the blood:
- Serum iron test: This test measures the amount of iron in the blood.
- Serum ferritin: This test measures how much iron is stored in the body. When blood iron levels are low, your body will pull from these stores of the mineral as supplementation.
- Total iron-binding capacity (TIBC): A TIBC test measures the levels of free transferrin present in the blood. Transferrin is a protein that carries iron through the blood. Transferrin free from iron may indicate low iron levels.
- Transferrin test: A transferrin test measures transferrin levels in the blood.
Your doctor may recommend or order an iron test if they suspect that you have an excessive or deficient level of the mineral in your blood. This can help diagnose conditions such as iron overload (excess iron) or anemia (low red blood cell counts caused by chronic iron deficiency).