Iron Sat
The percentage of transferrin's iron-binding capacity that is currently occupied.
What is it
Iron saturation is calculated as serum iron divided by TIBC. It reflects how much of the body's iron transport capacity is currently in use.
Why it's measured
Iron saturation has been used in evaluating iron deficiency and overload in clinical research.
Reference range
Standard laboratory reference
20 – 50 %
Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.
Where does your number land?
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Drag to your own Iron Saturation % result.
Educational only, not a diagnosis. Ranges vary by laboratory. See which panel includes Iron Saturation %.
What results may indicate
Elevated
Has been associated with iron overload and hemochromatosis in research literature.
Lower
Has been associated with iron deficiency in research literature.
These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.
When it's measured
Calculated from serum iron and TIBC.
Related markers
Common questions
Iron saturation is calculated as serum iron divided by TIBC. It reflects how much of the body's iron transport capacity is currently in use.
It's one of the markers used to build a fuller picture of your health. On its own it tells you very little, so it's most informative when reviewed alongside related markers.
It's measured from a standard blood draw at Quest or LabCorp. Iron Saturation % is one of the markers included in the OPTML Apex Panel, where your results are read across systems and reviewed by a U.S.-licensed physician.
Reference ranges vary by laboratory, and a single value rarely tells the whole story. Review your result with a physician in the context of your other markers, symptoms, and history.
Iron Saturation % is one signal among many. Answer a few quick questions and we’ll point you to the panel that fits.
Measured in
A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.
Find the right panel →This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.
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