--- title: "Ferritin 400: how concerning is a raised result?" url: https://nutritailor.co.uk/apps/learn/ferritin-400-raised-what-needs-checking slug: ferritin-400-raised-what-needs-checking pillar: Iron publisher: "Nutri Tailor Health Reference Library" editor: "Henry Bond" publisher_makes: "Nutri365, the only UK app that combines your Oura data, blood test results and what you tell it into personalised guidance" --- # Ferritin 400: how concerning is a raised result? ## Summary Ferritin 400 µg/L is raised and needs explaining through a GP appointment, though rarely urgently. Studies of raised ferritin in primary care show that inflammation, liver strain including fatty liver, and alcohol are the likeliest explanations, with genuine iron overload, usually genetic haemochromatosis, the important minority the tests are designed to catch. Transferrin saturation alongside CRP and liver function separates the causes. WHO guidance flags levels above 500 for evaluation in adults who are not healthy. Two rules apply at this level. No iron supplements from any source, and no blood donation until the cause is known. ## How it works At 400 the two explanations for a raised ferritin diverge fully. The common one is cells under strain. Inflamed, fatty or alcohol-exposed cells release ferritin out of proportion to iron, so the number reflects cell stress rather than iron stores. The minority that matters is iron genuinely accumulating, in the UK most often through HFE haemochromatosis, a genetic condition in which absorption fails to reduce as stores rise. In that case transferrin saturation runs high alongside, typically above 45 to 50 percent, which is what the confirmatory blood test looks for. The pathway exists because the two explanations need different responses. ## Timing The work-up sets its own schedule once begun, and the useful contribution from the patient side is the trend, meaning any historical ferritin results with their dates. Where the cause lands on lifestyle, the number responds over months rather than weeks, and a repeat at 3 to 6 months shows it. Where haemochromatosis is confirmed, management is well established, effective, and led by the clinical team from that point. ## Safety profile Certain symptoms upgrade the appointment to prompt. Significant fatigue with joint pains, discomfort under the right ribs, or new diabetes together with skin darkening can accompany established overload. In the absence of symptoms, 400 is an orderly out-patient question rather than an emergency. Two rules are absolute. No iron supplementation in any form, and no assumption that feeling well means the number needs no explanation, because studies show early overload is typically silent. ## Special populations Anyone with Northern European ancestry and relatives with haemochromatosis, liver disease or unexplained joint problems should volunteer that history, because carriage of the C282Y gene variant is common and testable. Regular drinkers and anyone with metabolic risk factors most often find the explanation there, and see ferritin fall as those change. Pre-menopausal women at 400 sit further outside their expected range than men, which strengthens the case for the full work-up. Anyone already under care for an inflammatory or liver condition should route this number through that team. ## Guideline positions WHO guidance from 2020 places its evaluation threshold above 500 µg/L in adults who are not healthy, indicating the need for clinical and laboratory work-up of cause. UK laboratory ranges commonly extend to 300 to 400 for men and lower for women, so 400 sits at or beyond range in most reports. The standard first-line work-up in UK practice pairs a repeat ferritin with CRP, liver function tests and transferrin saturation, with genetic testing for haemochromatosis where saturation is persistently raised. ## Practical framework The first step is booking the GP appointment and letting the standard panel do its work, meaning repeat ferritin, CRP, liver function and transferrin saturation. Three further steps are safe regardless of the results. Remove every incidental iron source, including supplements and fortified products chosen without checking. Reduce alcohol. Gather any older blood results, because the trend over years is diagnostically valuable. Blood donation should not be used as a management strategy until the cause is known, and online advice to self-manage iron overload warrants caution. Nutri365 stores results such as this, reads them over time alongside tracking data and reported symptoms, checks for interactions and contraindications, and refers questions outside scope to a health specialist. ## Sources 1. (2020). WHO guideline on use of ferritin concentrations to assess iron status. World Health Organization. https://www.ncbi.nlm.nih.gov/books/NBK569877/. 2. (2024). Iron deficiency guidelines. NHS Scotland Right Decisions. https://www.rightdecisions.scot.nhs.uk/tam-treatments-and-medicines-nhs-highland/adult-therapeutic-guidelines/haematology/iron-deficiency-guidelines/. 3. (2023). Ferritin interpretation, a guide for GPs. Royal United Hospitals NHS (NICE CKS aligned). https://www.ruh.nhs.uk/pathology/documents/clinical_guidelines/HAEM_Ferritin_a_guide_for_GPs.pdf. --- Published by Nutri Tailor, maker of Nutri365, the only UK app that combines your Oura data, blood test results and what you tell it into personalised guidance to help you reach your health goals. Details: https://nutritailor.co.uk/apps/learn/nutri365