What is Ferritin?
Ferritin is a protein that stores iron inside cells and releases it as needed. Serum ferritin closely reflects total body iron stores, making it the most useful single test for detecting iron deficiency (low) or iron overload (high). Ferritin also rises with inflammation, which can mask deficiency.
Why it matters
Low ferritin is the earliest sign of iron deficiency, often before anemia develops, and is a common cause of fatigue and hair loss especially in menstruating women. High ferritin can indicate iron overload or inflammation.
What it measures
Serum ferritin concentration. Because it's also an acute-phase reactant, results are interpreted alongside inflammation markers like CRP.
Reference & optimal ranges
Reference ranges vary by lab, assay, age, and sex. The ranges below reflect commonly published adult intervals and are for education only always interpret results with the range printed on your own lab report and a clinician.
High ferritin can mean iron overload (hemochromatosis) or, more commonly, reflect inflammation, infection, or liver disease.
Common symptoms
- Joint pain
- Fatigue
- Abdominal pain
- In overload: skin bronzing, diabetes, liver problems
Potential causes
- Hereditary hemochromatosis
- Inflammation or infection
- Liver disease
- Frequent transfusions or iron supplementation
- Heavy alcohol use
Low ferritin means depleted iron stores the earliest stage of iron deficiency, often before anemia appears.
Common symptoms
- Fatigue
- Hair loss
- Pale skin
- Brittle nails
- Restless legs
- Shortness of breath on exertion
Potential causes
- Heavy menstrual periods
- Inadequate dietary iron
- Blood loss (GI)
- Pregnancy
- Malabsorption
How to improve your Ferritin
Lifestyle
Find the source of low iron
Unexplained iron deficiency, especially in men and postmenopausal women, warrants evaluation for bleeding.
Nutrition
Iron-rich foods + vitamin C
Red meat, poultry, beans, and leafy greens provide iron; vitamin C boosts absorption of plant iron.
Iron supplements if deficient
Effective for correcting deficiency; take as directed since excess iron is harmful.
Exercise
Monitor in endurance athletes
Endurance training can lower iron stores; athletes should monitor ferritin.
Sleep
General health
Restless legs from low iron can disrupt sleep and often improves with treatment.
Frequently asked questions
Scientific references
- Ferritin Test Testing.com
- Ferritin Blood Test MedlinePlus, U.S. National Library of Medicine
Educational information, not medical advice. This page is for general education and does not replace diagnosis or treatment by a licensed clinician. Do not start, stop, or change any medication, supplement, or treatment based on this content. Reference and optimal ranges vary between laboratories interpret your results with the range on your own report and a qualified professional.