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Marker · Ranges for learning, not a diagnosis

Ferritin

Also called serum ferritin.

A protein in blood that shows how much iron is stored. It rises when iron stores are high. It also rises when something in the body is inflamed.

Read this first

  • Coach, not doctor. Aaron Cuha is a coach, not a doctor. No medical credential is claimed for him, or for these pages. A number on a blood test is something to talk over with a doctor, not something to diagnose yourself with. Nothing here is a prescription, a plan to follow, or a reason to start or stop a medicine. Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use.
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Why a longevity audience asks

This is the number that rules something out of the owner's stack. His published ferritin is 435, and the rule is no iron, including inside a multivitamin. High ferritin is also how doctors watch iron overload disease. Low ferritin is a different story, and still not a reason to take iron on your own without a doctor.

How a coach reads it

Labs publish their own normal ranges, often about 30 to 400 ng/mL depending on sex and test method. The owner's 435 is above the top of many of those ranges. In one study of 422 people being treated for an inherited iron overload disease (HFE hemochromatosis), a value over 1,000 went with a higher risk of death. That is for a doctor to handle, not a supplement decision. This is not a diagnosis.

Units on this page: ng/mL, ug/L

When it is low

May mean iron stores are low. Confirm it with the rest of the iron tests and a blood count before anyone talks about a bottle. Pregnancy, bleeding, and gut problems that block absorption change what tests you need.

When it is high

Do not take iron. Do not take a multivitamin that hides iron. Inflammation, alcohol, liver disease and iron overload can all raise ferritin. Get a doctor to sort out which one.

Easy ways to misread it

  • Ferritin is not a clean iron-only number when CRP, an inflammation test, is up.
  • A greens powder or a men's multivitamin can still contain iron.
  • One high number does not mean you have iron overload disease (hemochromatosis).

What to ask your doctor

Ask for ferritin with an iron panel and a full blood count (CBC). If ferritin is high, ask for hs-CRP and whether a gene test for iron overload (HFE) or a specialist makes sense. Do not start iron first.

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