Transferrin Saturation
Iron Studies marker
Transferrin Saturation
Category: Iron Studies
Unit: %
Percentage of transferrin bound with iron. Indicates iron availability.
PED Notes
Low saturation with low ferritin confirms iron deficiency. Monitor in regular blood donors.
When high
When high (>45%) -- possible iron overload:
- Investigate hereditary haemochromatosis (HFE gene testing) if persistently >50%
- Reduce or stop iron supplementation
- Avoid Vitamin C supplements in excess (enhances iron absorption further)
- Blood donation is therapeutic for iron overload
- Check liver function -- iron overload causes hepatotoxicity (compounding oral AAS liver stress)
Pharmacological / therapeutic options for confirmed iron overload:
- Therapeutic phlebotomy -- 500mL every 1-2 weeks until ferritin <50 ug/L for confirmed haemochromatosis; then maintenance 500mL every 2-4 months; haematologist-supervised
- For non-hereditary iron overload (excess supplementation, transfusion history), donation every 8-12 weeks is usually sufficient
- Iron chelation (deferasirox / Exjade 20-40mg/kg/day, or deferoxamine parenteral) -- reserved for severe overload when phlebotomy is contraindicated or insufficient; physician-supervised; monitor renal/liver function and retinal toxicity
- Note: AAS-driven erythropoiesis increases iron utilisation, so iron overload in active cycle users is uncommon -- persistent elevation warrants HFE testing
When low
When low (<15%) -- confirms iron deficiency:
Supplements:
- Iron Bisglycinate -- 25-50mg elemental iron/day
- Vitamin C -- 500mg with iron dose to enhance absorption
- Low transferrin saturation + low ferritin = true iron deficiency -- supplementation is indicated
- Low transferrin saturation + normal/high ferritin = functional iron deficiency (iron trapped in stores, often from inflammation)
Context for AAS users:
- Regular blood donation to manage high haematocrit depletes iron stores rapidly
- Monitor transferrin saturation alongside ferritin every 8-12 weeks if donating regularly
- Target transferrin saturation 20-35% for optimal erythropoiesis
History Chart
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Frequently Asked Questions
Reference Ranges
Standard Range
15 - 45 %
VitalMetrics Range
20 - 45 %