Iron and haematology . Patient guide
Ferritin Blood Test
What is Ferritin
Ferritin is the main protein that stores iron inside cells, and the blood ferritin level is the most useful single marker of how much iron the body has in reserve. According to NICE CKS Anaemia (iron deficiency, August 2024 revision), a serum ferritin below 30 micrograms per litre is diagnostic of iron deficiency irrespective of sex; some hair-restoration clinicians additionally prefer ferritin above 70 ug/L before surgery, though this is specialist opinion rather than a NICE threshold. Iron deficiency is the commonest UK nutritional deficiency, particularly in menstruating women, and ferritin falls long before standard anaemia tests turn abnormal.
This biomarker entry is being clinically reviewed by our team. The factual content draws on UK guidance (NICE, NHS, Royal Colleges and the relevant speciality society where cited).
Reference range
Reported in ng/mL (also seen as µg/L (numerically equal)). Final reports always carry the issuing laboratory's range, which is what your clinician will interpret against.
| Group | Range | Note |
|---|---|---|
| Absent iron stores | under 15 | BSG 2021: a ferritin below 15 ug/L is indicative of absent iron stores |
| Low iron stores (iron deficiency) | under 30 | NICE CKS (Aug 2024 revision) treats under 30 ug/L as iron deficient irrespective of sex. BSG 2021: below 30 is generally indicative of low body iron stores |
| Borderline: can still fit iron deficiency | 30 to 45 | BSG 2021 suggests 45 ug/L as the best trade-off between sensitivity and specificity in practice. A result here with symptoms, anaemia or inflammation needs a clinician to read it in context |
| Lower limit printed on UK lab reports | 15 to 30 | BSG 2021: most laboratories set their lower limit within this range, so it varies between labs |
| Upper limit printed on UK lab reports | set by each lab | It differs between laboratories and with sex and age. Use the range on your own report |
| Iron deficiency unlikely | above 150 | BSG 2021: a ferritin above 150 ug/L is unlikely with absolute iron deficiency, even in the presence of inflammation. A high ferritin has other causes (see below) |
| Trichology view for hair shedding | above 70 | expert opinion (Rushton, Trost), not a NICE threshold and the evidence is limited; some hair clinicians aim above 70 ug/L when shedding is the presenting issue |
What it is
Iron is mostly held inside cells, bound to ferritin. A small amount of ferritin leaks into the bloodstream and the blood ferritin level reflects total body iron stores. Ferritin is also a mild acute-phase protein, which means it can rise during infection or inflammation, sometimes masking a true deficiency.
Why a clinician would order it
Ferritin is requested in the work-up of fatigue, hair shedding, restless legs, breathlessness on exertion, brittle nails, heavy menstrual bleeding, vegan or vegetarian diet review, post-partum recovery, and as part of pre-operative bloodwork (especially before a hair transplant).
If your level is outside the range
Symptoms of low Ferritin
- Fatigue, especially with exertion
- Hair shedding
- Brittle nails
- Breathlessness on stairs
- Restless legs
- Pica (craving ice or unusual substances)
- Reduced exercise tolerance
What low can indicate. Iron deficiency, often before anaemia appears on a full blood count. Common causes include dietary insufficiency, heavy menstrual bleeding, pregnancy and breastfeeding, malabsorption (coeliac, IBD), or occult gastrointestinal blood loss.
Symptoms of high Ferritin
- Joint pain
- Abdominal discomfort
- Persistent fatigue (uncommon)
- Skin pigmentation changes (advanced cases)
What high can indicate. Inflammation or recent infection (most common reason), iron overload (haemochromatosis), liver disease, regular alcohol intake, or rarely metabolic syndrome.
Testing tips
Ferritin on its own does not need fasting. Our panels that include iron studies (Hair Loss Essentials, Advanced Hair & Hormone Check, Pre-Transplant, Pre-Transplant + BBV and General Wellness) need a fast of at least 12 hours, with water only, so follow the instructions for the panel you book. A morning appointment between 8am and 10am is preferred on Hair Loss Essentials and General Wellness. Do not take iron tablets or supplements for 24 hours beforehand, and do not take a B12 supplement beforehand. If you have had a recent illness, ferritin may be transiently raised and a repeat in 4 to 6 weeks may give a clearer picture.
Related reading
- What Does Low Ferritin Feel Like? Symptoms, Causes and What Counts as Low What low ferritin feels like, what counts as low, what causes it and when to see a GP. Tiredness, hair shedding and brain fog can be linked to low ...
- Always Tired Despite Sleep? What Your Blood Can Tell You Sleeping enough but still exhausted? The treatable causes a blood test can find, why normal results can miss them, and when to see your GP instead.
Where you can get this tested
Ferritin is included in the following WMG Health panels. Same-day appointments are usually available at our Harley Street clinic, with results clinician-reviewed.
Want a specific combination of markers we do not have a panel for? Build a custom panel and our clinicians will design one for you.
Looking to book a test?
Private hair loss blood tests
Ferritin, iron studies and the thyroid and vitamin markers behind fatigue and hair shedding, reviewed by GMC-registered doctors.
Symptoms often investigated with Ferritin
Ferritin is commonly tested when patients present with the following symptoms. If any of these resonate with you, the linked guides explain what to look for and which test pathway is appropriate.
Read this marker alongside another
Ferritin is most useful when interpreted together with the markers below. Each guide walks through the 4-quadrant matrix our clinicians use when both come back at once.
Sources
UK guidance our clinicians use when interpreting this marker.
- NICE CKS: Anaemia (iron deficiency)
- NHS: Iron deficiency anaemia
- British Society of Gastroenterology: guidelines for the management of iron deficiency anaemia in adults (Gut, 2021)
This page is general patient information, not personal medical advice. A GMC-registered clinician will review your results and tailor any interpretation to you. See our Editorial Policy for how we write and review content.
Common questions about Ferritin
What is a normal Ferritin range?
Absent iron stores: under 15 (BSG 2021: a ferritin below 15 ug/L is indicative of absent iron stores). Low iron stores (iron deficiency): under 30 (NICE CKS (Aug 2024 revision) treats under 30 ug/L as iron deficient irrespective of sex. BSG 2021: below 30 is generally indicative of low body iron stores). Borderline: can still fit iron deficiency: 30 to 45 (BSG 2021 suggests 45 ug/L as the best trade-off between sensitivity and specificity in practice. A result here with symptoms, anaemia or inflammation needs a clinician to read it in context). Lower limit printed on UK lab reports: 15 to 30 (BSG 2021: most laboratories set their lower limit within this range, so it varies between labs). Upper limit printed on UK lab reports: set by each lab (It differs between laboratories and with sex and age. Use the range on your own report). Iron deficiency unlikely: above 150 (BSG 2021: a ferritin above 150 ug/L is unlikely with absolute iron deficiency, even in the presence of inflammation. A high ferritin has other causes (see below)). Trichology view for hair shedding: above 70 (expert opinion (Rushton, Trost), not a NICE threshold and the evidence is limited; some hair clinicians aim above 70 ug/L when shedding is the presenting issue). Always interpret your own results against the laboratory range printed on your report, since assay-specific reference ranges vary.
What does a low Ferritin result mean?
Iron deficiency, often before anaemia appears on a full blood count. Common causes include dietary insufficiency, heavy menstrual bleeding, pregnancy and breastfeeding, malabsorption (coeliac, IBD), or occult gastrointestinal blood loss.
What does a high Ferritin result mean?
Inflammation or recent infection (most common reason), iron overload (haemochromatosis), liver disease, regular alcohol intake, or rarely metabolic syndrome.
Do I need to fast or prepare for the Ferritin blood test?
Ferritin on its own does not need fasting. Our panels that include iron studies (Hair Loss Essentials, Advanced Hair & Hormone Check, Pre-Transplant, Pre-Transplant + BBV and General Wellness) need a fast of at least 12 hours, with water only, so follow the instructions for the panel you book. A morning appointment between 8am and 10am is preferred on Hair Loss Essentials and General Wellness. Do not take iron tablets or supplements for 24 hours beforehand, and do not take a B12 supplement beforehand. If you have had a recent illness, ferritin may be transiently raised and a repeat in 4 to 6 weeks may give a clearer picture.
What is a normal ferritin level for a woman in the UK?
There is no single UK figure, because each laboratory sets its own range and it is printed on your report. Most UK laboratories put the lower limit between 15 and 30 ug/L (BSG 2021). NICE CKS treats a ferritin below 30 ug/L as iron deficient, so a result just above the lower limit on your report can still be worth discussing if you have symptoms. Upper limits differ between laboratories and with sex and age, and a raised ferritin often reflects inflammation rather than iron overload, so a high result needs a clinician to interpret it.
Can ferritin be normal and iron still be low?
Yes. Ferritin is an acute-phase protein, so infection or inflammation can push it up even when iron stores are low. This is why ferritin is read alongside iron, total iron binding capacity, transferrin saturation and a full blood count, and why BSG 2021 suggests a higher cut-off of 45 ug/L in practice.
Can I order a Ferritin blood test privately in London?
Yes. WMG Health offers Ferritin in several standard panels and as part of a custom panel at our 134 Harley Street clinic. Results are released as each marker is reviewed, and the completion date is set by the slowest marker in your panel. We confirm the expected timeframe at booking. Book a standard panel online, or ask for a custom panel via /contact/ or 020 3239 3378.