Transferrin saturation
Transferrin saturation, abbreviated as TSAT and measured as a percentage, is a medical laboratory value. It is the ratio of serum iron and total iron-binding capacity. Of the transferrin that is available to bind iron, this value tells a clinician how much serum iron are actually bound. For instance, a value of 15% means that 15% of iron-binding sites of transferrin are being occupied by iron. For an explanation of some clinical situations in which this ratio is important, see Total iron-binding capacity. The three results are usually reported together.
Usual values
Normal reference ranges are:
- Serum iron: 60–170 μg/dl (10–30μmol/L)
- TIBC: 240–450 μg/dl
- Transferrin saturation: 15–50% (males), 12–45% (females)
μg/dl = micrograms per deciliter.
Laboratories often use different units and "normal" may vary by population and the lab techniques used. Look at the individual laboratory reference values to interpret a specific test (for instance, your own).
![](../I/m/Blood_values_sorted_by_mass_and_molar_concentration.png)