Ferritin is a protein produced mainly by the liver that stores iron in the body. Iron is needed to make red blood cells, which carry oxygen throughout the body.
A ferritin test helps check whether iron stores are too low or too high. It is often ordered with other blood tests, like a complete blood count, serum iron or transferrin, especially when anemia, inflammation or infection is suspected.
Low ferritin is usually linked to iron deficiency and can cause symptoms like fatigue, weakness, pale skin, hair loss, headaches and dizziness. High ferritin can occur with inflammation, infection, liver disease, some types of anemia or hemochromatosis, and treatment depends on the underlying cause.
Normal levels
Normal ferritin levels can vary according to age and sex. They can also vary slightly depending on the laboratory where the blood test is performed. In general, ferritin is measured in ng/mL.
Ferritin results should always be interpreted by a doctor, who will consider the person’s symptoms, health history and other test results. Ferritin can increase with inflammation, infection, liver disease and other conditions, even when iron stores are not high.
What results mean
A ferritin result should be assessed by a hematologist or general practitioner, who will also consider any presenting symptoms, the person's health history and other test results.
High ferritin
Symptoms of high ferritin may be a sign of high iron levels, which may occur with inflammation or infections. This protein can become elevated in cases of acute inflammation or infection, such as:
- COVID-19
- Hemolytic anemia
- Megaloblastic anemia
- Alcoholic hepatitis
- Hodgkin’s lymphoma
- Myocardial infarct in men
- Leukemia
- Hemochromatosis
Symptoms of high ferritin: Generally, people with high ferritin levels may feel joint pain, fatigue, shortness of breath or abdominal pain. Treatment for high ferritin varies according to the underlying cause, but blood dialysis may be recommended to level out excess amounts. Patients are advised to eat less foods that contain iron or vitamin C.
Low ferritin
Low ferritin levels usually indicate decreased iron levels. The liver stops producing iron as there is no iron available for storage. The main causes of low ferritin are:
- Iron deficient anemia
- Hypothyroidism
- Gastrointestinal bleed
- Intense menstrual bleeding
- Diet low in iron and vitamin C
Symptoms of low ferritin: Symptoms of low ferritin include fatigue, weakness, pallor, lack of appetite, hair loss, headaches and dizziness. Treatment can involve daily iron supplementation or iron-rich foods with vitamin C sources, like meat, beans and oranges.
Why it is ordered
The ferritin test is usually ordered to:
- Check the amount of iron in the body, especially if anemia is suspected
- Monitor the response to treatment, in the case of iron deficiency or hemochromatosis, for example
- Assess inflammation levels in the body along with other tests, due to infections and diseases such as rheumatoid arthritis.
However, the most common indication for the ferritin test is to assess the body's iron stores in the event of suspected anemia. The doctor will also often order other tests like a complete blood count and serum iron and/or blood transferrin, to confirm the diagnosis. Learn more about anemia blood tests your doctor may order.