Ferritin

What this test is

Ferritin is a blood test that shows how much iron your body has stored. Low iron can cause tiredness, restless legs, hair loss, or trouble exercising, even before your blood count shows anemia. Ferritin is the best single test for finding low iron. It makes sense to check if you have those symptoms, heavy periods, a plant-based diet, or you are pregnant. One thing to know: ferritin can also rise when your body is fighting an infection or inflammation, so a normal-looking number does not always rule out low iron if you are unwell at the same time. Your doctor may check one more marker to be sure. This test is not usually needed once a year if you have no symptoms or risk factors.