Health Reference LibraryFerritin: what your level means, low, normal and high (UK)
This entry is part of the Nutri Tailor Health Reference Library — cited research on supplements, nutrients and adjacent areas of health.
Summary
Ferritin is the blood test for iron stores, and the UK threshold that matters is 30 micrograms per litre: below it, NICE calls adult iron deficiency, even though many laboratory reports only flag results under 15. Between 30 and 50 clears the threshold but sits low. Healthy ranges run to about 200 for women and 300 for men. A high result is more often inflammation, liver, alcohol or weight than iron overload, and is sorted out with transferrin saturation, CRP and liver tests at the GP. Ferritin also rises with inflammation, so a normal result during illness can hide deficiency, and a CRP alongside settles it.
How it works
Ferritin is the protein that stores iron inside cells, and the small amount in the blood mirrors the size of those stores, which is why it is the first test to fall when iron runs low and the last to recover. It is also an acute-phase protein: any inflammation, infection, liver strain or excess weight pushes it up regardless of iron, so a normal or high result needs CRP alongside it to be read properly. Low stores show as tiredness, breathlessness on stairs, hair shedding, restless legs, cold hands and feet and cravings for ice, often before haemoglobin falls.
Special populations
Iron deficiency without anaemia is real and defined at this level; see low ferritin with normal haemoglobin. In women, heavy periods are the commonest cause. In men and post-menopausal women, UK guidance routes the cause to the GP first, explained in iron deficiency in men. In pregnancy the thresholds differ; see iron in pregnancy.
Guideline positions
Below 30 micrograms per litre is adult iron deficiency under NICE, even where the laboratory only flags under 15. 30 to 50 clears the threshold but sits low, and is the level at which symptoms are often reported and a trial with a retest is a fair question; see is a ferritin of 20 normal? and what ferritin level is optimal for women. Healthy ranges run to about 200 for women and 300 for men, covered in ferritin between 50 and 300. Above the range is usually not iron overload; transferrin saturation above 45 percent is the screening line, explained in transferrin saturation above 45 percent and high ferritin. No supplement lowers ferritin.
Practical framework
Read the number with the free blood test result interpreter. Get CRP if there was any illness, because inflammation masks iron deficiency. For confirmed deficiency, the form and the timeline are in which form of iron and how long does iron take. Retest after eight weeks; stores take three to six months to refill. Nutri Tailor stocks iron bisglycinate with vitamin C.
Sources
- NICE Clinical Knowledge Summary (CKS, UK government). Anaemia - iron deficiency. NICE Clinical Knowledge Summaries (CKS).
- WHO guideline on use of ferritin concentrations to assess iron status in individuals and populations. World Health Organization (WHO).
- Snook J, Bhala N, Beales ILP, Cannings D, Kightley C, Logan RPH, Pritchard DM, Sidhu R, Surgenor S, Thomas W, Verma AM 2021. British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults. Gut. PMID: 34497146 · DOI: 10.1136/gutjnl-2021-325210