what is ferritin in blood
Definition. A ferritin test measures the amount of ferritin in your blood. Ferritin is a blood cell protein that contains iron. A ferritin test helps your doctor understand how much iron your body is storing.f a ferritin test reveals that your blood ferritin level is lower than normal, it indicates your body's iron stores are low and you have iron deficiency. If a ferritin test shows higher than normal levels, it could indicate that you have a condition that causes your body to store too much iron.