The main iron-transport protein in blood; part of iron-status panels with ferritin and iron.
What it is
Transferrin carries iron in plasma. Levels often rise when iron stores are low and can fall in inflammation or malnutrition. It is read with serum iron, ferritin, and sometimes TIBC or transferrin saturation.
Why it matters
High transferrin with low ferritin supports iron deficiency patterns; low transferrin with inflammation can mask iron interpretation.
This guide is educational only and cannot diagnose you. Discuss results, especially anything outside your laboratory’s reference interval, or that does not match how you feel, with a GP or other appropriately qualified clinician.
How it affects the body
Without enough transport capacity or iron cargo, haemoglobin production and tissue iron delivery suffer: tiredness and reduced training tolerance may follow.
For athletes
Endurance athletes often watch transferrin with ferritin after heavy blocks or heavy periods. Do not start high-dose iron from one panel alone.
