--- title: "Haemoglobin 105: what your result means" url: https://nutritailor.co.uk/apps/learn/haemoglobin-105-what-your-result-means slug: haemoglobin-105-what-your-result-means 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" --- # Haemoglobin 105: what your result means ## Summary A haemoglobin of 105 g/L is below the UK sex-specific reference thresholds of roughly 130 g/L for men and 120 g/L for women, the definition of anaemia. UK pathways read the result with red cell size and ferritin to identify the cause, and unexplained anaemia always warrants a GP conversation before correction. ## How it works Haemoglobin is the oxygen-carrying protein inside red blood cells, and the blood level reflects how much oxygen-carrying capacity is circulating right now. It sits downstream of iron stores: ferritin falls first, and haemoglobin follows only once stores are too depleted to sustain red cell production, so a low haemoglobin usually means the underlying picture has been developing for some time. B12 and folate status, chronic illness, kidney function and blood loss all move the number as well, which is why a low result prompts a wider look rather than a single-nutrient conclusion. UK reports give haemoglobin in grams per litre. ## Guideline positions UK reference ranges for haemoglobin are sex-specific: results below roughly 130 g/L in men and 120 g/L in women are classed as anaemia, with pregnancy using lower thresholds again. NICE anaemia pathways start from the full blood count picture, using red cell size and ferritin to separate iron deficiency from B12 or folate causes and from anaemia of chronic disease. A result just under the threshold reads differently from one far below it, and UK guidance classes unexplained anaemia as a finding that always warrants a GP conversation to establish the cause before anything else. ## Practical framework A haemoglobin of 105 g/L sits below both UK sex thresholds: 15 under the female reference of 120 g/L and 25 under the male reference of 130 g/L, so this result is classed as anaemia for anyone, and the distance below the line shapes how quickly the cause needs establishing. A haemoglobin below the sex-specific threshold, roughly 130 g/L for men and 120 g/L for women, is classed as anaemia in UK practice, and unexplained anaemia is always a GP conversation first, because the cause matters more than the number. The blood count usually carries the first clues: smaller, paler red cells point towards iron deficiency, larger cells towards B12 or folate shortfall, and normal-sized cells towards chronic illness or recent blood loss. Ferritin alongside the result usually settles the iron question. How far below the threshold the result sits shapes urgency: a few points under with a known heavy-period history reads differently from a result tens of points down with no obvious cause. Where iron deficiency is confirmed as the driver, correction of stores is the evidence-supported route, and haemoglobin typically responds over several weeks once the cause is addressed, with a repeat count confirming direction. One reading trap: UK reports use grams per litre, so 118 g/L is the same result as 11.8 in the g/dL format some apps and US sources use. ## Sources 1. 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. 2. 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Diagnosis and management of hemochromatosis: 2011 practice guideline by the American Association for the Study of Liver Diseases. Hepatology. PMID: 21452290. DOI: 10.1002/hep.24330. 6. European Association for the Study of the Liver (lead authors: Zoller H, Schaefer B, Vanclooster A, Loustaud-Ratti V, Bardou-Jacquet E, Pietrangelo A; et al) (2022). EASL Clinical Practice Guidelines on haemochromatosis. J Hepatol. PMID: 35662478. DOI: 10.1016/j.jhep.2022.03.033. 7. Fertrin KY (2020). Diagnosis and management of iron deficiency in chronic inflammatory conditions (CIC): is too little iron making your patient sick?. Hematology Am Soc Hematol Educ Program. PMID: 33275757. DOI: 10.1182/hematology.2020000132. 8. Mei Z, Addo OY, Jefferds MED, Flores-Ayala RC, Brittenham GM (2024). Physiologically based trimester-specific serum ferritin thresholds for iron deficiency in US pregnant women. Blood Advances. PMID: 38781318. DOI: 10.1182/bloodadvances.2024013460. 9. NIH Office of Dietary Supplements. NIH Office of Dietary Supplements — Iron Fact Sheet for Health Professionals. NIH Office of Dietary Supplements (US government). https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/. --- 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