What Does Ferritin Mean?
Ferritin is your body's iron storage protein. Low ferritin means depleted iron stores — often the earliest sign of iron deficiency, even before anemia develops.
What Ferritin Measures
Ferritin is a protein that stores iron inside your cells (mostly in the liver, spleen, and bone marrow). Blood ferritin levels reflect how much iron you have in reserve. Low ferritin means your iron stores are running out — and your body will soon struggle to make new red blood cells.
Normal Ranges
Normal (men)24–336 ng/mL
Normal (women)11–307 ng/mL
Depleted iron stores< 30 ng/mL
Severely low< 15 ng/mL
Reference ranges may vary slightly by lab. Always use the range provided on your specific test report.
What Affects Your Ferritin Level
- Inadequate dietary iron
- Heavy menstrual bleeding
- GI blood loss (ulcers, hemorrhoids)
- Malabsorption (celiac disease, gastric bypass)
- Endurance exercise (runners often have low ferritin)
- Vegetarian or vegan diets without careful planning