Iron and haematology . Patient guide
Ferritin
Ferritin is the main protein that stores iron inside cells. A blood ferritin level is the most useful single marker of how much iron your body has in reserve, and it 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 |
|---|---|---|
| Adult men | 30 to 400 | lower limit varies between UK labs |
| Adult women (pre-menopause) | 15 to 200 | |
| Adult women (post-menopause) | 30 to 400 | |
| Optimal for hair growth (clinical view) | 70 to 200 | many clinicians aim above 70 for symptomatic patients |
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
No fasting required. Avoid iron supplements for at least 24 hours before testing for a true baseline. 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.
Where you can get this tested
Ferritin is included in the following WMG Health panels. Same-day appointments 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.
Sources
UK guidance our clinicians use when interpreting this marker.
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.