Transferrin Saturation
Transferrin saturation captures the proportion of transferrin binding sites occupied by iron. It combines information from serum iron and TIBC into a single transport-efficiency marker.
Unit: % · 12 slices · age and sex · 1 source
Filed under panels: Iron Studies · topics: Hematology
These pages use transferrin saturation from the NHANES iron-status dataset. NHANES calculates transferrin saturation as serum iron divided by TIBC, multiplied by 100. It is particularly useful alongside ferritin because it shows how fully iron-transport capacity is occupied, not just how much iron is circulating or stored.
Population Distribution
Browse by Demographic
| Age (years) | male (%) | female (%) |
|---|---|---|
| 20-29 | 15–52 (29) | 7–47 (22) |
| 30-39 | 15–49 (29) | 7–46 (22) |
| 40-49 | 17–51 (30) | 7–50 (24) |
| 50-59 | 16–48 (29) | 11–45 (25) |
| 60-69 | 11–51 (28) | 14–41 (26) |
| 70+ | 14–49 (28) | 12–42 (25) |
Frequently Asked Questions
What does transferrin saturation add beyond serum iron alone?
Serum iron can change substantially over short intervals. Transferrin saturation adds context by comparing iron concentration with the total available binding capacity, which helps distinguish low supply from low transport availability.
Why is transferrin saturation useful in iron deficiency workup?
Low transferrin saturation can highlight under-occupied iron transport even when ferritin or serum iron alone is harder to interpret. It is commonly read together with ferritin and TIBC.
Is transferrin saturation measured or derived?
In NHANES it is derived as serum iron divided by TIBC times 100, using the iron-status dataset.