Transferrin Saturation

Percentage of transferrin binding sites occupied by iron, calculated from serum iron and total iron-binding capacity. A sensitive early marker of iron availability and a screen for iron overload.
Also known as:
TSAT
Iron Saturation
SAT
.

Transferrin Saturation ranges

Interpret your result
"Normal" lab range for Transferrin Saturation is between 16 and 60%:
16
60
According to OptimalDX, Transferrin Saturation should be between 24 and 35%:
24
35
Optimal range
Optimal range for Transferrin Saturation appears to be between 22 and 37%:
0
18
22
37
45
80
Why this optimal range?
Preliminary range is based on functional health organizations including but not limited to those listed above.

What a low value may mean:

Common reasons for low Transferrin Saturation:

  • Low transferrin saturation usually reflects reduced circulating iron availability. It is common in iron deficiency.

    Low TSAT can also be seen in chronic inflammation, infection, autoimmune disease, kidney disease, and malignancy, where hepcidin-mediated iron sequestration reduces circulating iron availability despite normal or elevated ferritin. Obesity and insulin resistance may be associated with this inflammatory low-iron-availability pattern.

What a high value may mean:

Common reasons for high Transferrin Saturation:

  • High transferrin saturation reflects excess circulating iron relative to binding capacity. TSAT is sensitive to recent iron intake, fasting status, and time of day, so high values should be interpreted cautiously after recent iron supplementation or a non-fasting blood draw.

    High TSAT can also be seen with liver disease, and disorders with ineffective erythropoiesis or hemolysis, such as sideroblastic anemia, thalassemia/myelodysplasia, and some hemolytic anemias.

    ,

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Zsolt Szabo
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