Transferrin Saturation
Transferrin saturation shows how large a share of the iron-transport protein transferrin is carrying iron.
Transferrin saturation shows how large a share of the iron-transport protein transferrin is carrying iron. It is given as a percentage and calculated from the iron value and the transferrin value or TIBC. It describes how much iron is on its way to the cells that need it, and is read together with ferritin, which reflects the iron stores. Retesting shows how it changes over time.
Iron intake and uptake matter most. Low intake of iron-rich foods, blood loss through heavy periods or frequent blood donation, pregnancy and hard endurance training tend to lower it. Iron supplements and a meal just before the test can raise it. Iron in the blood varies through the day and is usually highest in the morning, and inflammation after a recent infection can lower it for a while.
Foods that help
Iron-rich foods such as red meat, poultry, fish, shellfish, legumes, tofu, dark leafy greens and fortified cereals. Vitamin C from fruit, berries and vegetables at the same meal helps the body take up iron from plant foods.
Foods to limit
Coffee and tea with iron-rich meals, and large amounts of calcium at the same meal, reduce iron uptake. Iron supplements or high-dose vitamin C without a clear need. Large amounts of alcohol.
Track it through the year
One value is a snapshot. Following it up shows whether what you changed is working.
Related markers
Educational information only — not a diagnosis. Every result is checked against safe limits, and anything critical is escalated for follow-up.
See all 84 markers →