Iron, vitamins and folate
Ferritin blood test: what a high or low result means
What a ferritin blood test measures, what low or high ferritin can mean, and what to ask your doctor.
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Explain my results → Available on web, iOS & Android.What is ferritin?
Ferritin is a protein that stores iron inside your body. The small amount in your blood reflects how much iron you have in reserve, so a ferritin test is the main way doctors check your iron stores. It is often requested alongside a full blood count when someone has anaemia or tiredness.
Why is this test done?
- To check for iron deficiency, the most common cause of anaemia
- To investigate tiredness, hair loss or restless legs
- To monitor iron treatment
- To look for iron overload, for example in haemochromatosis
What does a high ferritin mean?
A high ferritin can mean too much iron is stored in the body, but more often it is raised for other reasons, because ferritin also rises with inflammation.
Possible reasons include:
- Inflammation or infection
- Liver conditions, including fatty liver
- Regular alcohol use
- Obesity, diabetes or other metabolic conditions
- Iron overload conditions such as haemochromatosis
- Repeated blood transfusions
What does a low ferritin mean?
A low ferritin almost always means iron deficiency. However, because ferritin is also a protein that rises with inflammation, a 'normal' ferritin reading can sometimes mask iron deficiency if you are unwell or have a chronic inflammatory condition.
Possible reasons include:
- Heavy or long periods
- Pregnancy
- A diet low in iron, including some vegetarian and vegan diets
- Blood loss from the gut, for example from ulcers or bowel conditions
- Poor iron absorption, such as in coeliac disease
- Frequent blood donation
Why we don't list a "normal range". Reference ranges differ between laboratories and can depend on your age, sex and whether you are pregnant. The range printed next to your result on your own report is the one that applies to you, so use that, and talk to your doctor about what your result means for you.
What can affect your ferritin result?
- Inflammation or infection, which can push ferritin up and hide iron deficiency
- Iron tablets or infusions
- Liver conditions and alcohol
- Your age and sex
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Try it with your own results → Paste, upload or photograph your results.Questions to ask your doctor
- Are my iron stores low enough to need treatment?
- What do you think is causing my low iron?
- Should I take iron tablets, how should I take them, and for how long?
- Could inflammation be affecting my ferritin result?
- When should I be retested?
Frequently asked questions
Can my ferritin be low if my haemoglobin is normal?
Yes. Ferritin often falls before haemoglobin does, so low ferritin can be an early sign of iron deficiency before anaemia develops.
Why might I be referred for stomach or bowel tests?
If there is no obvious reason for low iron, especially in men and in women who no longer have periods, doctors usually check the stomach and bowel for slow bleeding, even if you have no gut symptoms. This is a routine precaution, and most people turn out not to have a serious cause.
Does high ferritin mean I have too much iron?
Not always. Ferritin also rises with inflammation, infection, liver conditions and alcohol. Your doctor may check other iron tests, such as transferrin saturation, to tell these apart.
What is the difference between iron and ferritin tests?
A serum iron test measures iron circulating in your blood at that moment, which changes a lot through the day. Ferritin reflects your iron stores, so it is usually more useful for spotting iron deficiency.
Can Patiently AI explain my ferritin result?
Yes. Paste your results, or upload a photo, PDF or Word file, and Patiently AI explains them in plain English, sticking to the numbers and ranges on your own report rather than adding its own, and suggests questions to ask your doctor. It is free, needs no account, and removes identifying details on your device first.