A ferritin blood test checks the amount of ferritin in the blood. Ferritin is a protein in the body that binds to iron; most of the iron stored in the body is bound to ferritin. Ferritin is found in the liver, spleen, skeletal muscles, and bone marrow. Only a small amount of ferritin is found in the blood. The amount of ferritin in the blood shows how much iron is stored in your body.
Check to see if iron treatment to raise or lower the iron level is working.
How To Prepare
In general, there's nothing you have to do before this test, unless your doctor tells you to.
How It Is Done
A health professional uses a needle to take a blood sample, usually from the arm.
How It Feels
When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch.
There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.
Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you.
Very high ferritin levels can mean a large buildup of iron in the body (hemochromatosis). One form of this condition is passed on in families (genetic hemochromatosis). Some diseases, including alcohol use disorder, thalassemia, and some types of anemia that cause red blood cells to be destroyed, can also cause hemochromatosis. Also, if you have many blood transfusions, this can sometimes cause the body to store too much iron (acquired hemochromatosis).
Too much iron in body organs, such as the pancreas or heart, can affect how the organ works.
Low ferritin levels often mean an iron deficiency is present. This can be caused by long-term (chronic) blood loss from heavy menstrual bleeding, pregnancy, not enough iron in the diet, or bleeding inside the intestinal tract (from ulcers, colon polyps, colon cancer, hemorrhoids, or other conditions). In rare cases, too much iron may be lost through the skin (because of a disease such as psoriasis) or in the urine.