Ferritin
A blood test that measures the body's iron storage protein, used to evaluate iron deficiency, anemia, and iron overload conditions.
Last updated: April 10, 2026
Iron deficiency is the most common nutritional deficiency worldwide, affecting an estimated 1.6 billion people. Ferritin is the earliest and most sensitive blood marker of iron depletion — it often drops before other iron markers or hemoglobin show any change.
Why Is Ferritin Tested?
Ferritin is a protein that stores iron inside cells and releases it when the body needs it. A small amount of ferritin circulates in the blood, and this serum ferritin level closely reflects the body's total iron reserves.
Unlike serum iron, which fluctuates throughout the day based on meals and other factors, ferritin provides a more stable picture of long-term iron status. A healthcare provider may order a ferritin test to:
- Evaluate suspected iron deficiency or iron deficiency anemia
- Screen for iron overload conditions such as hereditary hemochromatosis
- Investigate unexplained fatigue, weakness, or hair loss
- Monitor iron stores during pregnancy
- Track response to iron supplementation or treatment
- Help interpret abnormal results on a complete blood count (CBC)
Ferritin is frequently ordered alongside serum iron, total iron-binding capacity (TIBC), and transferrin saturation to provide a complete picture of iron metabolism.
Normal Reference Ranges
Ferritin ranges vary significantly by sex, age, and laboratory. Always use the ranges provided on the specific lab report.
| Group | Normal Range | Unit |
|---|---|---|
| Adult Men | 20 – 500 ng/mL | ng/mL (mcg/L) |
| Adult Women (premenopausal) | 20 – 200 ng/mL | ng/mL (mcg/L) |
| Adult Women (postmenopausal) | 20 – 300 ng/mL | ng/mL (mcg/L) |
| Status | Ferritin Level |
|---|---|
| Depleted Iron Stores | Below 12 ng/mL |
| Low-Normal (may warrant monitoring) | 12 – 30 ng/mL |
| Adequate | 30 – 300 ng/mL (varies by sex) |
| Elevated (investigate further) | Above 500 ng/mL |
What Does a HIGH Ferritin Level Mean?
Elevated ferritin does not always mean iron overload. Ferritin is an acute phase reactant, meaning it rises in response to inflammation regardless of actual iron stores. Interpreting high ferritin requires looking at the full clinical picture.
Possible causes of elevated ferritin include:
- Hereditary hemochromatosis — a genetic condition causing excessive iron absorption
- Chronic inflammation — rheumatoid arthritis, lupus, and other inflammatory conditions
- Liver disease — hepatitis, fatty liver disease, cirrhosis, and alcohol-related liver damage
- Metabolic syndrome and obesity — associated with chronic low-grade inflammation
- Infections — acute or chronic infections raise ferritin as part of the immune response
- Certain cancers — leukemia, lymphoma, and other malignancies
- Frequent blood transfusions — can lead to iron accumulation
True iron overload can damage the liver, heart, and pancreas if untreated. Transferrin saturation is typically checked alongside ferritin to distinguish iron overload from inflammation-related elevations.
What Does a LOW Ferritin Level Mean?
Low ferritin is highly specific for iron deficiency. It is the earliest marker to decline when the body's iron stores begin to drop, often falling before hemoglobin or serum iron show changes.
Common causes of low ferritin include:
- Inadequate dietary iron intake — especially in vegetarian or vegan diets
- Heavy menstrual periods — the most common cause of iron deficiency in premenopausal women
- Chronic blood loss — gastrointestinal bleeding from ulcers, polyps, or colon cancer
- Pregnancy — increased iron demands for the growing fetus and expanded blood volume
- Malabsorption — celiac disease, inflammatory bowel disease, or gastric bypass surgery
- Frequent blood donation — each donation removes approximately 250 mg of iron
- Intense physical training — endurance athletes, particularly runners, may experience increased iron losses
Symptoms of iron depletion may include fatigue, weakness, pale skin, shortness of breath, brittle nails, hair loss, restless legs, and difficulty concentrating. Low ferritin can progress to iron deficiency anemia if not addressed.
Factors That Can Affect Your Results
Several variables can influence ferritin levels independent of actual iron status:
- Inflammation or infection — even a mild cold can temporarily raise ferritin, potentially masking iron deficiency
- Alcohol consumption — heavy drinking increases ferritin through liver inflammation
- Recent iron supplements — taking iron shortly before testing can affect results
- Menstrual cycle timing — ferritin may be slightly lower during or just after menstruation
- Obesity — adipose tissue produces inflammatory cytokines that raise ferritin
- Liver damage — damaged liver cells release stored ferritin into the bloodstream
- Time of day — ferritin itself is relatively stable, but serum iron (often drawn at the same time) varies throughout the day
Should I Be Concerned?
Ferritin results are best interpreted alongside other iron studies rather than in isolation. A single abnormal ferritin level does not always indicate a serious problem.
Results that may warrant closer attention include:
- Ferritin below 12 ng/mL — strongly indicates depleted iron stores
- Ferritin below 30 ng/mL with symptoms (fatigue, hair loss, restless legs) — may benefit from supplementation even if technically "in range"
- Ferritin above 500 ng/mL — warrants investigation for iron overload, liver disease, or underlying inflammation
- Ferritin above 1,000 ng/mL — requires prompt evaluation as this level is associated with significant organ damage risk
- Persistently elevated ferritin with high transferrin saturation (above 45%) — raises suspicion for hemochromatosis
A healthcare provider can combine ferritin results with serum iron, TIBC, transferrin saturation, hemoglobin, and clinical symptoms to determine the appropriate next steps.
Common Next Steps
Depending on the result, a healthcare provider may recommend:
- Oral iron supplementation — ferrous sulfate, ferrous gluconate, or ferrous fumarate, typically taken with vitamin C to enhance absorption
- IV iron infusion — for severe deficiency, malabsorption, or when oral iron is not tolerated
- Dietary modifications — increasing iron-rich foods (red meat, spinach, lentils, fortified cereals)
- Additional iron studies — serum iron, TIBC, transferrin saturation to complete the picture
- Complete blood count (CBC) — to check hemoglobin and red blood cell indices for anemia
- Genetic testing for hemochromatosis — HFE gene testing if iron overload is suspected
- Investigation for bleeding sources — stool occult blood test, endoscopy, or colonoscopy if chronic blood loss is suspected
- Follow-up testing — rechecking ferritin after 2–3 months of supplementation
Frequently Asked Questions
What is a normal ferritin level?
Normal ferritin is approximately 20–500 ng/mL for adult men and 20–200 ng/mL for premenopausal women. Ranges vary by laboratory. Postmenopausal women typically have ranges closer to men due to cessation of menstrual iron loss.
Is ferritin the same as iron?
No. Ferritin is a protein that stores iron. Serum ferritin reflects total iron reserves in the body. Serum iron measures iron circulating in the blood at that moment. Both tests offer different but complementary information about iron status.
Can ferritin be high with low iron?
Yes. Because ferritin is an acute phase reactant, it can be elevated by inflammation, infection, or liver disease even when iron stores are actually low. This is called "functional iron deficiency" and is common in chronic disease. Additional markers like TIBC and transferrin saturation help clarify the picture.
Can low ferritin cause hair loss?
Studies suggest a connection between low ferritin and hair shedding (telogen effluvium). Some dermatologists recommend maintaining ferritin above 40–70 ng/mL for optimal hair growth. If low ferritin is contributing to hair loss, iron supplementation may help over several months.
How long does it take to raise ferritin?
With oral iron supplementation, improvement often begins within 2–4 weeks, but fully replenishing iron stores typically takes 3–6 months. IV iron works faster. A healthcare provider will usually recheck levels after 2–3 months and may continue supplementation for several months after ferritin normalizes.
Does fasting affect ferritin results?
Fasting is not strictly required for ferritin alone, but it is often recommended because serum iron (frequently ordered together) is affected by recent food intake. For the most consistent results, a morning fasting blood draw is typically preferred.
Is ferritin checked during pregnancy?
Ferritin testing is frequently recommended during pregnancy because iron demands increase substantially. Low ferritin in pregnancy is associated with iron deficiency anemia, preterm birth, and low birth weight. Many providers check ferritin in the first trimester and may recheck later.
What is hemochromatosis?
Hereditary hemochromatosis is a genetic condition that causes the body to absorb too much iron from food. Over time, excess iron accumulates in organs (especially the liver, heart, and pancreas), potentially causing serious damage. It is one of the most common genetic disorders in people of Northern European descent and is treatable with regular phlebotomy (blood removal).
What is the difference between ferritin and transferrin saturation?
Ferritin measures stored iron. Transferrin saturation measures the percentage of transferrin (an iron transport protein) carrying iron in the blood. A ferritin of 500 ng/mL with a normal transferrin saturation may indicate inflammation rather than iron overload, while high ferritin with transferrin saturation above 45% is more suggestive of true iron overload.
Can exercise lower ferritin?
Intense endurance exercise can reduce ferritin over time through several mechanisms: foot-strike hemolysis (red blood cell damage from running impact), increased iron loss through sweat, and GI micro-bleeding during prolonged exercise. Endurance athletes, particularly female runners, are at higher risk for iron depletion and may benefit from periodic ferritin monitoring.
Sources
- WHO. Iron Deficiency Anaemia: Assessment, Prevention, and Control. World Health Organization; 2001.
- Camaschella C. Iron-Deficiency Anemia. N Engl J Med. 2015;372(19):1832-1843.
- Knovich MA, et al. Ferritin for the Clinician. Blood Rev. 2009;23(3):95-104.
- MedlinePlus. Ferritin Blood Test. U.S. National Library of Medicine.
- Adams PC, et al. Hemochromatosis and Iron-Overload Screening in a Racially Diverse Population. N Engl J Med. 2005;352(17):1769-1778.
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Disclaimer: This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Reference ranges vary by laboratory and individual factors. Always discuss results with a qualified healthcare provider.