Ferritin is one of the most common blood tests ordered when someone has unexplained hair shedding, especially women. This guide explains what ferritin is, why it is checked in hair loss, how to understand results in general terms, and why interpretation belongs to your doctor.
What ferritin is
Ferritin is a protein that stores iron inside cells. A small amount circulates in the blood, and the level in a blood test reflects the body's iron stores. Low ferritin is one of the earliest signs of iron deficiency, often appearing before anemia develops. See iron deficiency hair loss.
Why it is checked in hair loss
Low iron stores have been associated with increased hair shedding, particularly telogen effluvium, and with thinning in women. Checking ferritin helps a clinician find a possible contributor that can be corrected. It is often ordered alongside a complete blood count and thyroid tests.
Understanding results
Labs report a reference range, and a result below the lab's range generally indicates low iron stores. In hair loss, some clinicians look for a ferritin level comfortably within the normal range rather than just above the lower limit, though views differ and research is ongoing. Your doctor will interpret your result in the context of your symptoms, other blood tests and health history.
One important caveat: ferritin also rises with inflammation, infection and some liver conditions. A normal or high ferritin can therefore sometimes hide low iron, which is why doctors may look at other iron tests too.
If your ferritin is low
- Your doctor will look for the cause, such as heavy periods, diet, absorption problems or blood loss. Unexplained low iron in men and postmenopausal women needs medical investigation.
- Treatment may include dietary changes or supplements, as your doctor advises. Do not start iron supplements without testing and medical advice, since too much iron can be harmful.
- Repeat testing is often used to check that stores are recovering.
- Hair recovers gradually after iron stores improve.
If your ferritin is normal
A normal ferritin points toward other causes of hair loss, such as pattern hair loss, stress-related shedding or thyroid problems. See TE vs androgenetic alopecia.
Next step
Ask your doctor about blood tests if you have unexplained shedding. If you want a licensed provider to review your hair loss, start your online consultation.
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