Ferritin
Also known as: Serum ferritin
Ferritin is a protein that stores iron in your body. Measuring it gives an indirect sense of how much iron you have in reserve, which is why it is often used to assess iron status.
Why it's measured
Ferritin is checked when looking into iron levels, certain types of anemia, or fatigue. It is also an “acute phase” marker, meaning it can rise with inflammation, so doctors interpret it carefully.
Typical range
Reference ranges for ferritin differ by lab and often by sex. Because inflammation can raise ferritin independently of iron stores, your doctor reads it alongside other iron tests.
What high values can mean
Higher ferritin can reflect higher iron stores or inflammation, among other things. Your doctor considers the broader picture before interpreting it.
What low values can mean
Lower ferritin often points toward reduced iron stores and is a common finding your doctor may explore further with related tests.
Questions to ask your doctor
- Does my ferritin suggest anything about my iron stores?
- Could inflammation be affecting this number?
- Should I have other iron studies done alongside it?
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Try the explainerEducational information only — not medical advice, diagnosis, or treatment. Reference ranges vary by lab; always use your own lab's range and discuss results with a qualified clinician.