Nutrients
Total iron-binding capacity (TIBC)
Included in Baseline and Complete.
Compare membershipsHow much room your blood has for iron.
TIBC estimates how much iron your blood proteins, mainly transferrin, could carry if they were fully loaded. It helps show how your body is responding to the amount of iron available.
TIBC tends to move opposite to your iron stores.
When iron stores run low, your body makes more transferrin to capture as much iron as possible, so TIBC tends to rise. When stores are high, TIBC tends to fall. Because of this, TIBC works best as part of an iron panel with ferritin, serum iron, and transferrin saturation.
TIBC can also be lower with inflammation, liver disease, or poor nutrition, and it can be affected by pregnancy and birth control pills.
When iron is scarce, your body builds more seats to carry it.
Questions
What does a high TIBC mean?
A high TIBC often goes with low iron stores, especially when ferritin and transferrin saturation are also low. It can also be higher in late pregnancy. Your clinician will read it with your blood counts and symptoms.
What does a low TIBC mean?
A low TIBC can be seen with iron overload, ongoing inflammation, liver disease, or low blood protein from poor nutrition. It's one piece of the iron picture, so your other markers and health history guide what it means for you.