Is my Transferrin Saturation normal?
Free blood test checker · Standard + longevity-optimal ranges
What is a normal TSAT level?
Transferrin saturation (TSAT) is the ratio of serum iron to TIBC, expressed as a percentage. Optimal range is 20-50%. Low saturation (< 20%) indicates iron deficiency. Saturation above 50% flags dangerous iron overload (hemochromatosis) — a genetic condition affecting ~1 in 200 people of Northern European descent that causes toxic iron accumulation in the liver, heart, and pancreas. TSAT is the best single screening test for hereditary hemochromatosis.
| Range | Values |
|---|---|
| Standard Reference | 20–50 % |
| High Risk | > 60 % |
| Low Risk | < 15 % |
What causes abnormal TSAT levels?
Low transferrin saturation is caused by iron deficiency anemia, chronic disease (inflammation diverts iron from circulation), and chronic blood loss. High transferrin saturation is caused by hereditary hemochromatosis (most important), iron supplementation overdose, hemolytic anemias (iron released from destroyed red blood cells), liver disease, and repeated blood transfusions.
When should you see a doctor?
See your doctor if transferrin saturation is below 15% (indicates iron deficiency) or above 45% (warrants hemochromatosis screening). TSAT above 60% is critical and requires urgent evaluation including HFE gene testing, ferritin, and liver function tests.
TSAT and longevity
Transferrin saturation is the most cost-effective screening test for hereditary hemochromatosis, a condition that causes premature organ damage when undetected. Iron overload is a potent driver of oxidative aging — free iron catalyzes Fenton reactions that generate hydroxyl radicals, the most damaging reactive oxygen species. Hemochromatosis patients diagnosed early and treated with regular phlebotomy have normal life expectancy. The longevity implications extend beyond hemochromatosis: even high-normal iron stores are associated with increased cancer, diabetes, and cardiovascular risk in population studies.
Where to get a TSAT test
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Related biomarkers
These biomarkers are often tested alongside TSAT for a more complete picture.
Frequently asked questions
What is a normal transferrin saturation?
What is hereditary hemochromatosis?
How is transferrin saturation calculated?
What does high transferrin saturation mean?
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Sources: Reference ranges based on AHA/ACC, ADA, and AACE clinical guidelines. Biological variation data from Ricos/Westgard database. Longevity-optimal ranges reflect targets used by preventive and functional medicine practitioners.
Last reviewed: April 2026. This tool provides general health information and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare provider about your specific results.