Ferritin Blood Test Results Explained

Plain-English guide · Last updated October 17, 2026 · Based on NIH and U.S. government sources

What the ferritin test measures

Ferritin is a protein that stores iron inside your cells. A small amount circulates in your blood, and the ferritin blood test measures it. That gives your doctor a picture of your iron stores (MedlinePlus).

Iron matters because your body uses it to make hemoglobin, the protein in red blood cells that carries oxygen from your lungs to the rest of your body. You also need it for growth and to make some hormones (NIH Office of Dietary Supplements). Ferritin is often checked along with other iron tests and a complete blood count.

What your ferritin level means

MedlinePlus does not give one normal range, because labs use different methods and ranges often differ by age and sex. Compare your result with the range printed on your lab report.

• Lower than normal ferritin may mean iron deficiency anemia or another condition related to low iron (MedlinePlus).
• Higher than normal ferritin can be caused by too much iron in your body, and also by other conditions (listed below).

MedlinePlus adds that an abnormal result doesn't always mean you have a condition that needs treatment, and certain medicines can raise or lower ferritin.

Why it matters

When iron stores run low, iron-deficiency anemia can set in. NHLBI notes that mild or moderate iron-deficiency anemia may cause no symptoms, while more serious cases can cause tiredness, shortness of breath, chest pain, dizziness, cold hands and feet and pale skin (NHLBI). MedlinePlus says untreated iron deficiency anemia can lead to heart problems, infections and other health issues (MedlinePlus).

Possible reasons for low ferritin

These are possible causes, not a diagnosis (NHLBI, NIH Office of Dietary Supplements):

• Blood loss: heavy menstrual periods, bleeding in the digestive tract (for example from ulcers or inflammatory bowel disease), injury or surgery, or frequent blood donation.
• Regular use of aspirin or NSAIDs such as ibuprofen and naproxen, which can lead to digestive tract bleeding.
• Absorption problems, such as celiac disease.
• Higher needs, such as pregnancy.
• Low intake. NIH ODS says vegetarians who don't eat meat, poultry or seafood need almost twice the usual recommended amount, because the body doesn't absorb plant (nonheme) iron as well.

Possible reasons for high ferritin

Again, possible causes, not a diagnosis. MedlinePlus lists too much iron in the body, plus inflammation (like from infection or surgery), an autoimmune disorder, liver disease, cancer, obesity, alcohol use disorder and hyperthyroidism (MedlinePlus). NIH ODS notes that some people have an inherited condition called hemochromatosis that causes iron to build up to toxic levels (NIH Office of Dietary Supplements).

Natural-first, plant-based iron tips to discuss with your doctor

If your doctor says your iron is low, these food ideas come from NIH ODS (NIH Office of Dietary Supplements):

• Eat iron-rich plant foods: white beans, lentils, kidney beans, peas, spinach, nuts and dried fruits like raisins.
• Choose iron-fortified breakfast cereals and breads.
• Pair plant iron with vitamin C foods such as citrus, strawberries, sweet peppers, tomatoes and broccoli. NIH ODS says vitamin C helps your body absorb iron from plant sources.

For reference, NIH ODS lists a daily recommended amount of 8 mg for adult men and for adults 51 and older, and 18 mg for women 19 to 50, with vegetarians needing almost twice as much. If ferritin is high, don't add iron; ask your doctor what's behind it first.

Supplement safety and medicine interactions

NIH ODS lists these interactions. Talk with your prescriber before taking iron if you use any of them, and don't change your medicines on your own:

• Levodopa (Parkinson's and restless legs): iron can reduce how much the body absorbs.
• Levothyroxine (thyroid medicine): taking iron with it can make it less effective. See our TSH guide.
• Proton pump inhibitors such as omeprazole and lansoprazole might reduce iron absorption from food.
• Calcium might interfere with iron absorption; taking them at different times may help.

When to talk to your doctor

• Your ferritin is flagged low or high.
• You feel tired, short of breath, dizzy or unusually pale, or have very heavy periods.
• You notice black or bloody stools, or other signs of bleeding.
• You have chest pain or severe shortness of breath: call 911.

Questions to ask at your next appointment

1. Is my ferritin low, normal or high for my age and sex?
2. Do I need other iron tests or a complete blood count?
3. Could bleeding, absorption or inflammation explain my result?
4. Can food changes be enough, or do I need a supplement? Which dose?
5. How should I time iron with my other medicines and supplements?
6. When should I retest?

Frequently asked questions

Sources

1. .govMedlinePlus (National Library of Medicine)Ferritin Blood Testmedlineplus.gov (opens in a new tab)
2. .govNIH Office of Dietary SupplementsIron Fact Sheet for Consumersods.od.nih.gov (opens in a new tab)
3. .govNIH Office of Dietary SupplementsIron Fact Sheet for Health Professionalsods.od.nih.gov (opens in a new tab)
4. .govNHLBI (National Institutes of Health)Iron-Deficiency Anemianhlbi.nih.gov (opens in a new tab)
5. .govNCCIH (National Institutes of Health)Using Dietary Supplements Wiselynccih.nih.gov (opens in a new tab)

Medical disclaimer: This article is general education, not medical advice. It does not diagnose, treat, cure or prevent any disease. Always talk with your doctor about your lab results, and talk with your prescriber before starting, stopping or changing any medicine or supplement. If you think you have a medical emergency, call 911. Last updated October 17, 2026.