{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T10:44:04Z","timestamp":1782297844968,"version":"3.54.5"},"reference-count":76,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T00:00:00Z","timestamp":1739404800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T00:00:00Z","timestamp":1739404800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100005690","name":"Universit\u00e4t des Saarlandes","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005690","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Curr Nutr Rep"],"abstract":"<jats:title>Abstract<\/jats:title>\n          <jats:sec>\n            <jats:title>Purpose of review<\/jats:title>\n            <jats:p>To define an intake threshold of vitamin B12 from food supplements that is sufficient to maintain normal body functions, but it does not cause pharmacological effects.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Recent findings<\/jats:title>\n            <jats:p>We used studies on the amount of B12 absorbed following oral B12 application and non-comparative case-series studies to synthesize evidence on pharmacological effects of oral B12 (between\u2009&lt;\u200910\u00a0\u00b5g and 3000\u00a0\u00b5g) in people with manifested deficiency. There is a dose-dependent intestinal absorption of B12 and in the same time effects on body metabolism and functions. Food supplements providing\u2009\u2264\u200920\u00a0\u00b5g B12 daily are unlikely to cause pharmacological effects, while 50\u00a0\u00b5g might correct abnormal biochemical markers in some deficient patients. Foods for special medical purposes for people who cannot absorb B12 may contain 100\u00a0\u00b5g to 150\u00a0\u00b5g B12. This dose may ensure 1\u20134\u00a0\u00b5g of the vitamin reaching the circulation on a\u00a0daily basis independent of intrinsic factor. Dosages\u2009\u2265\u2009200\u00a0\u00b5g\/d should be considered as drugs that can correct anemia, metabolic markers and clinical symptoms.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Summary<\/jats:title>\n            <jats:p>The content of vitamin B12 in food supplements should not exceed 20\u00a0\u00b5g. In addition, people with deficiency should receive appropriate medical treatment with high dose B12.<\/jats:p>\n          <\/jats:sec>","DOI":"10.1007\/s13668-025-00622-7","type":"journal-article","created":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T01:02:42Z","timestamp":1739408562000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A Framework to Guide Defining an Upper Threshold of Crystalline Vitamin B12 in Foods and Food Supplements"],"prefix":"10.1007","volume":"14","author":[{"given":"Rima","family":"Obeid","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juergen","family":"Geisel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Klaus","family":"Pietrzik","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emmanuel","family":"Andres","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,2,13]]},"reference":[{"key":"622_CR1","doi-asserted-by":"publisher","unstructured":"The German Federal Institute for Risk Assessment (Bundesinstitut f\u00fcr Risikobewertung, BfR. Maximum levels for the addition of vitamin B12 to foods including food supplements, 2021. https:\/\/doi.org\/10.17590\/20210331-122132","DOI":"10.17590\/20210331-122132"},{"key":"622_CR2","doi-asserted-by":"publisher","first-page":"104647","DOI":"10.1016\/j.yrtph.2020.104647","volume":"114","author":"S Thakkar","year":"2020","unstructured":"Thakkar S, Anklam E, Xu A, Ulberth F, Li J, Li B, et al. Regulatory landscape of dietary supplements and herbal medicines from a global perspective. Regul Toxicol Pharmacol. 2020;114:104647.","journal-title":"Regul Toxicol Pharmacol"},{"key":"622_CR3","doi-asserted-by":"crossref","unstructured":"EFSA Panel on Dietic Products, Nutrition and Allergies. Scientific openion on dietary reference values for cobalamin (vitamin B12). EFSA J. 2015;13:4150.","DOI":"10.2903\/j.efsa.2015.4150"},{"key":"622_CR4","volume-title":"DRI Dietary Reference Intakes: applications in dietary assessment","author":"National Academies of Sciences EaM","year":"2000","unstructured":"National Academies of Sciences EaM. DRI Dietary Reference Intakes: applications in dietary assessment. Washington, DC: The National Academies Press; 2000."},{"key":"622_CR5","doi-asserted-by":"publisher","first-page":"571","DOI":"10.3945\/ajcn.2009.28082","volume":"91","author":"MV Bor","year":"2010","unstructured":"Bor MV, von Castel-Roberts KM, Kauwell GP, Stabler SP, Allen RH, Maneval DR, et al. Daily intake of 4 to 7 microg dietary vitamin B-12 is associated with steady concentrations of vitamin B-12-related biomarkers in a healthy young population. Am J Clin Nutr. 2010;91:571\u20137.","journal-title":"Am J Clin Nutr"},{"key":"622_CR6","doi-asserted-by":"publisher","first-page":"52","DOI":"10.1093\/ajcn\/83.1.52","volume":"83","author":"MV Bor","year":"2006","unstructured":"Bor MV, Lydeking-Olsen E, Moller J, Nexo E. A daily intake of approximately 6 microg vitamin B-12 appears to saturate all the vitamin B-12-related variables in Danish postmenopausal women. Am J Clin Nutr. 2006;83:52\u20138.","journal-title":"Am J Clin Nutr"},{"key":"622_CR7","doi-asserted-by":"publisher","first-page":"324","DOI":"10.1111\/jhn.12814","volume":"34","author":"AM Baart","year":"2021","unstructured":"Baart AM, Balvers MGJ, de Vries JHM, Ten Haaf DSM, Hopman MTE, Klein Gunnewiek JMT. Relationship between intake and plasma concentrations of vitamin B12 and folate in 873 adults with a physically active lifestyle: a cross-sectional study. J Hum Nutr Diet. 2021;34:324\u201333.","journal-title":"J Hum Nutr Diet"},{"key":"622_CR8","unstructured":"Health and consumer protection Directorate-General of the European Commision. Directorate E - Safety of the food chain- Discussion paper on the setting of maximum and minimum amounts for vitamins and minerals in foodstuffs. 2006:1\u201327.  https:\/\/food.ec.europa.eu\/system\/files\/2016-10\/labelling_nutrition-vitamins_minerals-discus_paper_amount_vitamins_en.pdf."},{"key":"622_CR9","first-page":"4300","volume":"13","author":"EFSA Panel on Dietetic Products, Nutrition and Allergies NDA","year":"2015","unstructured":"EFSA Panel on Dietetic Products, Nutrition and Allergies NDA. Scientific and technical guidance on foods for special medical purposes in the context of Article 3 of Regulation (EU) No 609\/2013. EFSA J. 2015;13:4300.","journal-title":"EFSA J"},{"key":"622_CR10","unstructured":"Commission Delegated Regulation (EU). 2016\/128 of 25 September 2015 supplementing Regulation (EU) No 609\/2013 of the European Parliament and of the Council as regards the specific compositional and information requirements for food for special medical purposes. Official Journal of the European Union. 2021; L25\/30\u2013L25\/43. https:\/\/eur-lex.europa.eu\/legal-content\/EN\/TXT\/PDF\/?uri=CELEX:32016R0128."},{"key":"622_CR11","unstructured":"Bundesamt f\u00fcr Verbraucherschutz und Lebensmittelsi cherheit (BVL) und Bundesinstitut f\u00fcr Arzneimittel und Medizinprodukte (BfArM). Positionspapier des BVL und des BfArM: Charakterisierung von Lebensmitteln f\u00fcr besondere medizinische Zwecke (bilanzierten Di\u00e4ten). 2016:\u00a0https:\/\/www.bvl.bund.de\/SharedDocs\/Downloads\/01_Lebensmittel\/diaet\/Positionspapier_bilanzierte_Diaeten_2016_09_02.pdf?__blob=publicationFile&v=3. Accessed 12 Dec 2024."},{"key":"622_CR12","first-page":"229","volume":"70","author":"EB Healton","year":"1991","unstructured":"Healton EB, Savage DG, Brust JC, Garrett TJ, Lindenbaum J. Neurologic aspects of cobalamin deficiency Medicine (Baltimore). 1991;70:229\u201345.","journal-title":"Neurologic aspects of cobalamin deficiency Medicine (Baltimore)"},{"key":"622_CR13","doi-asserted-by":"publisher","first-page":"e071725","DOI":"10.1136\/bmj-2022-071725","volume":"383","author":"BH Wolffenbuttel","year":"2023","unstructured":"Wolffenbuttel BH, Owen PJ, Ward M, Green R. Vitamin B(12). BMJ. 2023;383:e071725.","journal-title":"BMJ"},{"key":"622_CR14","doi-asserted-by":"publisher","first-page":"1799","DOI":"10.1007\/s10072-017-3056-9","volume":"38","author":"JS Park","year":"2017","unstructured":"Park JS, Park D, Ko PW, Kang K, Lee HW. Serum methylmalonic acid correlates with neuropathic pain in idiopathic Parkinson\u2019s disease. Neurol Sci. 2017;38:1799\u2013804.","journal-title":"Neurol Sci"},{"key":"622_CR15","doi-asserted-by":"publisher","first-page":"1534","DOI":"10.1001\/archinte.161.12.1534","volume":"161","author":"AM Hvas","year":"2001","unstructured":"Hvas AM, Ellegaard J, Nexo E. Increased plasma methylmalonic acid level does not predict clinical manifestations of vitamin B12 deficiency. Arch Intern Med. 2001;161:1534\u201341.","journal-title":"Arch Intern Med"},{"key":"622_CR16","doi-asserted-by":"publisher","first-page":"970","DOI":"10.1097\/SLA.0000000000000214","volume":"258","author":"Y Hu","year":"2013","unstructured":"Hu Y, Kim HI, Hyung WJ, Song KJ, Lee JH, Kim YM, et al. Vitamin B(12) deficiency after gastrectomy for gastric cancer: an analysis of clinical patterns and risk factors. Ann Surg. 2013;258:970\u20135.","journal-title":"Ann Surg"},{"key":"622_CR17","doi-asserted-by":"publisher","first-page":"685","DOI":"10.7326\/M19-3781","volume":"173","author":"CA Schiavon","year":"2020","unstructured":"Schiavon CA, Bhatt DL, Ikeoka D, Santucci EV, Santos RN, Damiani LP, et al. Three-year outcomes of bariatric surgery in patients with obesity and hypertension\u202f: a randomized clinical trial. Ann Intern Med. 2020;173:685\u201393.","journal-title":"Ann Intern Med"},{"key":"622_CR18","doi-asserted-by":"publisher","first-page":"1005","DOI":"10.1016\/j.soard.2018.03.029","volume":"14","author":"W Schijns","year":"2018","unstructured":"Schijns W, Schuurman LT, Melse-Boonstra A, van Laarhoven CJHM, Berends FJ, Aarts EO. Do specialized bariatric multivitamins lower deficiencies after RYGB? Surg Obes Relat Dis. 2018;14:1005\u201312.","journal-title":"Surg Obes Relat Dis"},{"key":"622_CR19","doi-asserted-by":"publisher","first-page":"1447","DOI":"10.1038\/s41430-017-0074-x","volume":"72","author":"N Vilarrasa","year":"2018","unstructured":"Vilarrasa N, Fabregat A, Toro S, Gordejuela AG, Casajoana A, Montserrat M, et al. Nutritional deficiencies and bone metabolism after endobarrier in obese type 2 patients with diabetes. Eur J Clin Nutr. 2018;72:1447\u201350.","journal-title":"Eur J Clin Nutr"},{"key":"622_CR20","doi-asserted-by":"publisher","first-page":"823","DOI":"10.1007\/s13277-014-2705-3","volume":"36","author":"A Bilici","year":"2015","unstructured":"Bilici A, Sonkaya A, Ercan S, Ustaalioglu BB, Seker M, Aliustaoglu M, et al. The changing of serum vitamin B12 and homocysteine levels after gastrectomy in patients with gastric cancer: do they associate with clinicopathological factors? Tumour Biol. 2015;36:823\u20138.","journal-title":"Tumour Biol"},{"key":"622_CR21","doi-asserted-by":"publisher","first-page":"51","DOI":"10.1016\/j.dsx.2017.08.014","volume":"12","author":"K Gupta","year":"2018","unstructured":"Gupta K, Jain A, Rohatgi A. An observational study of vitamin b12 levels and peripheral neuropathy profile in patients of diabetes mellitus on metformin therapy. Diabetes Metab Syndr. 2018;12:51\u20138.","journal-title":"Diabetes Metab Syndr"},{"key":"622_CR22","doi-asserted-by":"publisher","first-page":"1061","DOI":"10.1111\/jgs.14761","volume":"65","author":"V Kancherla","year":"2017","unstructured":"Kancherla V, Elliott JL Jr, Patel BB, Holland NW, Johnson TM, Khakharia A, et al. Long-term metformin therapy and monitoring for vitamin B12 deficiency among older veterans. J Am Geriatr Soc. 2017;65:1061\u20136.","journal-title":"J Am Geriatr Soc"},{"key":"622_CR23","doi-asserted-by":"publisher","first-page":"179","DOI":"10.4158\/EP11009.OR","volume":"18","author":"E Kos","year":"2012","unstructured":"Kos E, Liszek MJ, Emanuele MA, Durazo-Arvizu R, Camacho P. Effect of metformin therapy on vitamin D and vitamin B(1)(2) levels in patients with type 2 diabetes mellitus. Endocr Pract. 2012;18:179\u201384.","journal-title":"Endocr Pract"},{"key":"622_CR24","doi-asserted-by":"publisher","first-page":"1283","DOI":"10.1007\/s00592-018-1240-x","volume":"55","author":"R Jayashri","year":"2018","unstructured":"Jayashri R, Venkatesan U, Rohan M, Gokulakrishnan K, Shanthi Rani CS, Deepa M, et al. Prevalence of vitamin B(12) deficiency in South Indians with different grades of glucose tolerance. Acta Diabetol. 2018;55:1283\u201393.","journal-title":"Acta Diabetol"},{"issue":"Suppl 1","key":"622_CR25","doi-asserted-by":"publisher","first-page":"S365","DOI":"10.1016\/j.dsx.2017.03.017","volume":"11","author":"S Bherwani","year":"2017","unstructured":"Bherwani S, Ahirwar AK, Saumya AS, Sandhya AS, Prajapat B, Patel S, et al. The study of association of Vitamin B(12) deficiency in type 2 diabetes mellitus with and without diabetic nephropathy in North Indian Population. Diabetes Metab Syndr. 2017;11(Suppl 1):S365\u20138.","journal-title":"Diabetes Metab Syndr"},{"key":"622_CR26","doi-asserted-by":"publisher","first-page":"e109878","DOI":"10.1371\/journal.pone.0109878","volume":"9","author":"D Kang","year":"2014","unstructured":"Kang D, Yun JS, Ko SH, Lim TS, Ahn YB, Park YM, et al. Higher prevalence of metformin-induced vitamin B12 deficiency in sulfonylurea combination compared with insulin combination in patients with type 2 diabetes: a cross-sectional study. PLoS ONE. 2014;9:e109878.","journal-title":"PLoS ONE"},{"key":"622_CR27","doi-asserted-by":"publisher","first-page":"253","DOI":"10.4103\/0022-3859.123143","volume":"59","author":"AK Singh","year":"2013","unstructured":"Singh AK, Kumar A, Karmakar D, Jha RK. Association of B12 deficiency and clinical neuropathy with metformin use in type 2 diabetes patients. J Postgrad Med. 2013;59:253\u20137.","journal-title":"J Postgrad Med"},{"key":"622_CR28","doi-asserted-by":"publisher","first-page":"87","DOI":"10.1080\/01639360903574734","volume":"29","author":"NR Rozgony","year":"2010","unstructured":"Rozgony NR, Fang C, Kuczmarski MF, Bob H. Vitamin B(12) deficiency is linked with long-term use of proton pump inhibitors in institutionalized older adults: could a cyanocobalamin nasal spray be beneficial? J Nutr Elder. 2010;29:87\u201399.","journal-title":"J Nutr Elder"},{"key":"622_CR29","doi-asserted-by":"publisher","first-page":"234","DOI":"10.1007\/s12603-014-0525-1","volume":"19","author":"AL Couderc","year":"2015","unstructured":"Couderc AL, Camalet J, Schneider S, Turpin JM, Bereder I, Boulahssass R, et al. Cobalamin deficiency in the elderly: aetiology and management: a study of 125 patients in a geriatric hospital. J Nutr Health Aging. 2015;19:234\u20139.","journal-title":"J Nutr Health Aging"},{"key":"622_CR30","doi-asserted-by":"publisher","first-page":"1154","DOI":"10.1016\/j.amjmed.2005.02.026","volume":"118","author":"E Andres","year":"2005","unstructured":"Andres E, Affenberger S, Vinzio S, Kurtz JE, Noel E, Kaltenbach G, et al. Food-cobalamin malabsorption in elderly patients: clinical manifestations and treatment. Am J Med. 2005;118:1154\u20139.","journal-title":"Am J Med"},{"key":"622_CR31","unstructured":"National Institute for Health and Care Excellence, NICE. Vitamin B12 deficiency in over 16s: diagnosis and management (NG239), 2024: http:\/\/www.nice.org.uk\/guidance\/ng239. Accessed 12 Dec 2024."},{"key":"622_CR32","doi-asserted-by":"publisher","first-page":"S40","DOI":"10.1177\/03795721241229500","volume":"45","author":"BHR Wolffenbuttel","year":"2024","unstructured":"Wolffenbuttel BHR, McCaddon A, Ahmadi KR, Green R. A brief overview of the diagnosis and treatment of cobalamin (B12) deficiency. Food Nutr Bull. 2024;45:S40\u20139.","journal-title":"Food Nutr Bull"},{"key":"622_CR33","doi-asserted-by":"publisher","first-page":"1017","DOI":"10.1002\/jimd.12677","volume":"46","author":"NN Stolwijk","year":"2023","unstructured":"Stolwijk NN, Bosch AM, Bouwhuis N, H\u00e4berle J, van Karnebeek C, van Spronsen FJ, et al. Food or medicine? A European regulatory perspective on nutritional therapy products to treat inborn errors of metabolism. J Inherit Metab Dis. 2023;46:1017\u201328.","journal-title":"J Inherit Metab Dis"},{"key":"622_CR34","doi-asserted-by":"publisher","first-page":"2847","DOI":"10.1007\/s00394-017-1553-5","volume":"57","author":"E Greibe","year":"2018","unstructured":"Greibe E, Mahalle N, Bhide V, Heegaard CW, Naik S, Nexo E. Increase in circulating holotranscobalamin after oral administration of cyanocobalamin or hydroxocobalamin in healthy adults with low and normal cobalamin status. Eur J Nutr. 2018;57:2847\u201355.","journal-title":"Eur J Nutr"},{"key":"622_CR35","first-page":"786","volume-title":"The megaloblastic anaemias","author":"I Chanarin","year":"1969","unstructured":"Chanarin I. The megaloblastic anaemias. London, United Kingdom: Blackwell; 1969. p. 786\u2013829."},{"key":"622_CR36","unstructured":"Institute of Medicine. Vitamin B12. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. USA: Washington, DC, National Academy Press, 2000: [306\u201356 pp]."},{"key":"622_CR37","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.1515\/zna-1965-0815","volume":"20","author":"HC Heinrich","year":"1965","unstructured":"Heinrich HC, Gabbe EE, Whang DDH, Wolfsteller E. Eine f\u00fcr die Berechnung der intestinalen Vitamin B12-Resorption beim Menschen sowohl im physiologischen, Intrinsic Factor-abh\u00e4ngigen als auch im unphysiologisch hohen, diffusionsbedingten Dosisbereich allgemein g\u00fcltige Formel. Zeitschrift fur Naturforschung B. 1965;20:1079.","journal-title":"Zeitschrift fur Naturforschung B"},{"key":"622_CR38","unstructured":"Heinrich HC. Nuklearmedizinische Untersuchungen des Vitamin B12-Stoffwechsels und des Eisenhaushalts. Aktuelle Gastroenterologie: Verh. 24. Tag. dtsch. Ges. Verdau-u. Stoffwechselkr., Hamburg 1967. Stuttgart: Thieme. 1968:249\u201379."},{"key":"622_CR39","doi-asserted-by":"publisher","first-page":"915","DOI":"10.1136\/bmj.2.4685.915","volume":"2","author":"CC Ungley","year":"1950","unstructured":"Ungley CC. Absorption of vitamin B12 in pernicious anemia. IV. Administration into buccal cavity, into washed segment of intestine, or after partial sterilization of bowel. Br Med J. 1950;2:915\u20139.","journal-title":"Br Med J"},{"key":"622_CR40","unstructured":"Berlin H, Berlin R, Brante G, Sj\u00f6berg SG. The absorption of IF-bound and free B12 in various clinical conditions. In Vitamin B12 and Intrinsic Factor, 2 Europ\u00e4isches Symposium, Hamburg, 1961 (Ed. H.C. Heinrich). Vitamin B12 and Intrinsic Factor. Stuttgart: Ferdinand Enke Verlag Stuttgart; 1962. pp. 485\u201395."},{"key":"622_CR41","doi-asserted-by":"publisher","first-page":"361","DOI":"10.1056\/NEJM195902192600803","volume":"260","author":"EA Brody","year":"1959","unstructured":"Brody EA, Estern S, Wasserman LR. Treatment of pernicious anemia by oral administration of vitamin B12 without added intrinsic factor. N Engl J Med. 1959;260:361\u20137.","journal-title":"N Engl J Med"},{"key":"622_CR42","doi-asserted-by":"publisher","first-page":"810","DOI":"10.7326\/0003-4819-58-5-810","volume":"58","author":"SO Waife","year":"1963","unstructured":"Waife SO, Jansen CJ Jr, Crabtree RE, Grinnan EL, Fouts PJ. Oral vitamin B12 without intrinsic factor in the treatment of pernicious anemia. Ann Intern Med. 1963;58:810\u20137.","journal-title":"Ann Intern Med"},{"key":"622_CR43","unstructured":"Chanarin I. The absorption of vitamin B12. In The Megaloblastic Anaemias. Blackwell Scientific Publications, Oxford and Edinburgh. 1969: [140\u201391 pp]."},{"key":"622_CR44","doi-asserted-by":"publisher","first-page":"8","DOI":"10.1093\/oxfordjournals.bmb.a069721","volume":"15","author":"DL Mollin","year":"1959","unstructured":"Mollin DL. Radioactive vitamin B12 in the study of blood diseases. Br Med Bull. 1959;15:8\u201313.","journal-title":"Br Med Bull"},{"key":"622_CR45","doi-asserted-by":"publisher","first-page":"1789","DOI":"10.1046\/j.1532-5415.2002.50506.x","volume":"50","author":"S Rajan","year":"2002","unstructured":"Rajan S, Wallace JI, Brodkin KI, Beresford SA, Allen RH, Stabler SP. Response of elevated methylmalonic acid to three dose levels of oral cobalamin in older adults. J Am Geriatr Soc. 2002;50:1789\u201395.","journal-title":"J Am Geriatr Soc"},{"key":"622_CR46","doi-asserted-by":"publisher","first-page":"390","DOI":"10.3945\/ajcn.112.033951","volume":"97","author":"C Dullemeijer","year":"2013","unstructured":"Dullemeijer C, Souverein OW, Doets EL, van der Voet H, van Wijngaarden JP, de Boer WJ, et al. Systematic review with dose-response meta-analyses between vitamin B-12 intake and European Micronutrient Recommendations Aligned\u2019s prioritized biomarkers of vitamin B-12 including randomized controlled trials and observational studies in adults and elderly persons. Am J Clin Nutr. 2013;97:390\u2013402.","journal-title":"Am J Clin Nutr"},{"key":"622_CR47","doi-asserted-by":"publisher","first-page":"1579","DOI":"10.1136\/bmj.1.5239.1579","volume":"1","author":"NK Shinton","year":"1961","unstructured":"Shinton NK. Oral treatment of pernicious anaemia with vitamin-B(12)-peptide. Br Med J. 1961;1:1579\u201382.","journal-title":"Br Med J"},{"key":"622_CR48","doi-asserted-by":"publisher","first-page":"225","DOI":"10.1159\/000513888","volume":"99","author":"T Namikawa","year":"2021","unstructured":"Namikawa T, Maeda M, Yokota K, Iwabu J, Munekage M, Uemura S, et al. Enteral vitamin B12 supplementation is effective for improving anemia in patients who underwent total gastrectomy. Oncology. 2021;99:225\u201333.","journal-title":"Oncology"},{"key":"622_CR49","doi-asserted-by":"publisher","first-page":"280","DOI":"10.1001\/archinte.1960.03820020120018","volume":"106","author":"PA McIntyre","year":"1960","unstructured":"McIntyre PA, Hahn R, Masters JM, Krevans JR. Treatment of pernicious anemia with orally administered cyanocobalamin (vitamin B12). Arch Intern Med. 1960;106:280\u201392.","journal-title":"Arch Intern Med"},{"key":"622_CR50","doi-asserted-by":"publisher","first-page":"13","DOI":"10.1016\/j.curtheres.2005.02.001","volume":"66","author":"E Andres","year":"2005","unstructured":"Andres E, Henoun LN, Noel E, Maloisel F, Vinzio S, Kaltenbach G, et al. Effects of oral crystalline cyanocobalamin 1000 \u00b5g\/d in the treatment of pernicious anemia: An open-label, prospective study in ten patients. Curr Ther Res Clin Exp. 2005;66:13\u201322.","journal-title":"Curr Ther Res Clin Exp"},{"key":"622_CR51","doi-asserted-by":"crossref","unstructured":"Didangelos T, Karlafti E, Kotzakioulafi E, Margariti E, Giannoulaki P, Batanis G et al. Vitamin B12 supplementation in diabetic neuropathy: A 1-year, randomized, double-blind, placebo-controlled trial. Nutrients 2021;13.","DOI":"10.3390\/nu13020395"},{"key":"622_CR52","doi-asserted-by":"publisher","first-page":"288","DOI":"10.1007\/s11695-007-9310-0","volume":"18","author":"AG Vargas-Ruiz","year":"2008","unstructured":"Vargas-Ruiz AG, Hernandez-Rivera G, Herrera MF. Prevalence of iron, folate, and vitamin B12 deficiency anemia after laparoscopic Roux-en-Y gastric bypass. Obes Surg. 2008;18:288\u201393.","journal-title":"Obes Surg"},{"key":"622_CR53","doi-asserted-by":"publisher","first-page":"87","DOI":"10.1016\/j.clnu.2020.04.029","volume":"40","author":"D Antoine","year":"2021","unstructured":"Antoine D, Li Z, Quilliot D, Sirveaux MA, Meyre D, Mangeon A, et al. Medium term post-bariatric surgery deficit of vitamin B12 is predicted by deficit at time of surgery. Clin Nutr. 2021;40:87\u201393.","journal-title":"Clin Nutr"},{"key":"622_CR54","first-page":"17","volume":"90","author":"Y Adali","year":"2022","unstructured":"Adali Y, Binnetoglu K. Evaluation of the response to vitamin B12 supplementation in patients with atrophy in sleeve gastrectomy materials. Cir Cir. 2022;90:17\u201323.","journal-title":"Cir Cir"},{"key":"622_CR55","first-page":"1","volume":"21","author":"CC Ungley","year":"1951","unstructured":"Ungley CC. Vitamin B12. II. A review of the clinical aspects. Nutr Abstr Rev. 1951;21:1\u201326.","journal-title":"Nutr Abstr Rev"},{"key":"622_CR56","doi-asserted-by":"publisher","first-page":"585","DOI":"10.1136\/bmj.2.4679.585","volume":"2","author":"BE Hall","year":"1950","unstructured":"Hall BE. Studies on the nature of the intrinsic factor of Castle. Br Med J. 1950;2:585\u20139.","journal-title":"Br Med J"},{"key":"622_CR57","doi-asserted-by":"publisher","first-page":"499","DOI":"10.3181\/00379727-91-22306","volume":"91","author":"S Estern","year":"1956","unstructured":"Estern S, Wassermann LR. Pernicious anemia I: Remission by small oral doses of purified vitamin B12. Proc Soc Exp Biol Med. 1956;91:499\u2013503.","journal-title":"Proc Soc Exp Biol Med"},{"key":"622_CR58","doi-asserted-by":"publisher","first-page":"1298","DOI":"10.1016\/S0140-6736(58)90574-9","volume":"2","author":"JN Chalmers","year":"1958","unstructured":"Chalmers JN, Shinton NK. Absorption of orally administered vitamin B12 in pernicious anaemia. Lancet. 1958;2:1298\u2013302.","journal-title":"Lancet"},{"key":"622_CR59","doi-asserted-by":"publisher","first-page":"1179","DOI":"10.1136\/bmj.1.4872.1179","volume":"1","author":"JN Chalmers","year":"1954","unstructured":"Chalmers JN, Hall ZM. Treatment of pernicious anaemia with oral vitamin B12 without known source of intrinsic factor. Br Med J. 1954;1:1179\u201381.","journal-title":"Br Med J"},{"key":"622_CR60","doi-asserted-by":"publisher","first-page":"454","DOI":"10.1093\/ajcp\/20.5.454","volume":"20","author":"LM Meyer","year":"1950","unstructured":"Meyer LM, Sawitsky A, Ritz ND, Krim M. Oral treatment of pernicious anemia with subminimal doses of folic acid and vitamin B12. Am J Clin Pathol. 1950;20:454\u20137.","journal-title":"Am J Clin Pathol"},{"key":"622_CR61","doi-asserted-by":"publisher","first-page":"1302","DOI":"10.1016\/S0140-6736(58)90575-0","volume":"2","author":"EH Hemsted","year":"1958","unstructured":"Hemsted EH, Mills J. Vitamin B12 in pernicious anaemia; intramuscular or oral. Lancet. 1958;2:1302\u20133.","journal-title":"Lancet"},{"key":"622_CR62","doi-asserted-by":"publisher","first-page":"577","DOI":"10.1016\/S0140-6736(62)90447-6","volume":"2","author":"RB Thompson","year":"1962","unstructured":"Thompson RB, Ashby DW, Armstrong E. Long-term trial of oral vitamin B12 in pernicious anaemia. Lancet. 1962;2:577\u20139.","journal-title":"Lancet"},{"key":"622_CR63","doi-asserted-by":"publisher","first-page":"3963","DOI":"10.21873\/anticanres.15891","volume":"42","author":"T Aoyama","year":"2022","unstructured":"Aoyama T, Maezawa Y, Cho H, Saigusa Y, Tamura J, Tsuchida K, et al. Phase II study of a multi-center randomized controlled trial to evaluate oral vitamin B12 treatment for vitamin B12 deficiency after total gastrectomy in gastric cancer patients. Anticancer Res. 2022;42:3963\u201370.","journal-title":"Anticancer Res"},{"key":"622_CR64","doi-asserted-by":"publisher","first-page":"1916","DOI":"10.1007\/s11695-017-3102-y","volume":"28","author":"KK Mahawar","year":"2018","unstructured":"Mahawar KK, Reid A, Graham Y, Callejas-Diaz L, Parmar C, Carr WR, et al. Oral vitamin B12 supplementation after Roux-en-Y gastric bypass: a systematic review. Obes Surg. 2018;28:1916\u201323.","journal-title":"Obes Surg"},{"key":"622_CR65","doi-asserted-by":"publisher","first-page":"254","DOI":"10.1007\/s11695-016-2449-9","volume":"27","author":"HJ Smelt","year":"2017","unstructured":"Smelt HJ, Pouwels S, Smulders JF. Different supplementation regimes to treat perioperative vitamin B12 deficiencies in bariatric surgery: a systematic review. Obes Surg. 2017;27:254\u201362.","journal-title":"Obes Surg"},{"key":"622_CR66","doi-asserted-by":"publisher","first-page":"1013","DOI":"10.1016\/j.soard.2013.04.017","volume":"9","author":"S Majumder","year":"2013","unstructured":"Majumder S, Soriano J, Louie CA, Dasanu CA. Vitamin B12 deficiency in patients undergoing bariatric surgery: preventive strategies and key recommendations. Surg Obes Relat Dis. 2013;9:1013\u20139.","journal-title":"Surg Obes Relat Dis"},{"key":"622_CR67","doi-asserted-by":"publisher","first-page":"e033687","DOI":"10.1136\/bmjopen-2019-033687","volume":"10","author":"T Sanz-Cuesta","year":"2020","unstructured":"Sanz-Cuesta T, Escortell-Mayor E, Cura-Gonzalez I, Martin-Fernandez J, Riesgo-Fuertes R, Garrido-Elustondo S, et al. Oral versus intramuscular administration of vitamin B12 for vitamin B12 deficiency in primary care: a pragmatic, randomised, non-inferiority clinical trial (OB12). BMJ Open. 2020;10:e033687.","journal-title":"BMJ Open"},{"key":"622_CR68","first-page":"CD004655","volume":"3","author":"H Wang","year":"2018","unstructured":"Wang H, Li L, Qin LL, Song Y, Vidal-Alaball J, Liu TH. Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency. Cochrane Database Syst Rev. 2018;3:CD004655.","journal-title":"Cochrane Database Syst Rev"},{"key":"622_CR69","first-page":"38","volume":"3","author":"CQ Chan","year":"2016","unstructured":"Chan CQ, Low LL, Lee KH. Oral vitamin B12 replacement for the treatment of pernicious anemia. Front Med (Lausanne). 2016;3:38.","journal-title":"Front Med (Lausanne)"},{"key":"622_CR70","doi-asserted-by":"publisher","first-page":"177","DOI":"10.1016\/j.orcp.2021.02.002","volume":"15","author":"RJ Ramos","year":"2021","unstructured":"Ramos RJ, Mottin CC, Alves LB, Mulazzani CM, Padoin AV. Vitamin B12 supplementation orally and intramuscularly in people with obesity undergoing gastric bypass. Obes Res Clin Pract. 2021;15:177\u20139.","journal-title":"Obes Res Clin Pract"},{"key":"622_CR71","doi-asserted-by":"publisher","first-page":"694","DOI":"10.1007\/s11695-014-1441-5","volume":"25","author":"CE Moore","year":"2015","unstructured":"Moore CE, Sherman V. Effectiveness of B vitamin supplementation following bariatric surgery: rapid increases of serum vitamin B12. Obes Surg. 2015;25:694\u20139.","journal-title":"Obes Surg"},{"key":"622_CR72","doi-asserted-by":"publisher","first-page":"1191","DOI":"10.1182\/blood.V92.4.1191","volume":"92","author":"AM Kuzminski","year":"1998","unstructured":"Kuzminski AM, Del Giacco EJ, Allen RH, Stabler SP, Lindenbaum J. Effective treatment of cobalamin deficiency with oral cobalamin. Blood. 1998;92:1191\u20138.","journal-title":"Blood"},{"key":"622_CR73","first-page":"3","volume":"10","author":"E Andres","year":"2006","unstructured":"Andres E, Kaltenbach G, Noblet-Dick M, Noel E, Vinzio S, Perrin AE, et al. Hematological response to short-term oral cyanocobalamin therapy for the treatment of cobalamin deficiencies in elderly patients. J Nutr Health Aging. 2006;10:3\u20136.","journal-title":"J Nutr Health Aging"},{"key":"622_CR74","doi-asserted-by":"publisher","first-page":"1755","DOI":"10.3324\/haematol.13122","volume":"93","author":"MV Bor","year":"2008","unstructured":"Bor MV, Cetin M, Aytac S, Altay C, Ueland PM, Nexo E. Long term biweekly 1 mg oral vitamin B12 ensures normal hematological parameters, but does not correct all other markers of vitamin B12 deficiency. A study in patients with inherited vitamin B12 deficiency. Haematologica. 2008;93:1755\u20138.","journal-title":"Haematologica"},{"key":"622_CR75","doi-asserted-by":"publisher","first-page":"247","DOI":"10.1111\/j.0954-6820.1968.tb02452.x","volume":"184","author":"H Berlin","year":"1968","unstructured":"Berlin H, Berlin R, Brante G. Oral treatment of pernicious anemia with high doses of vitamin B12 without intrinsic factor. Acta Med Scand. 1968;184:247\u201358.","journal-title":"Acta Med Scand"},{"key":"622_CR76","doi-asserted-by":"publisher","first-page":"217","DOI":"10.1016\/j.ajcnut.2024.05.019","volume":"120","author":"V Lacombe","year":"2024","unstructured":"Lacombe V, Vinatier E, Roquin G, Copin MC, Delattre E, Hammi S, et al. Oral vitamin B12 supplementation in pernicious anemia: a prospective cohort study. Am J Clin Nutr. 2024;120:217\u201324.","journal-title":"Am J Clin Nutr"}],"container-title":["Current Nutrition Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s13668-025-00622-7.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s13668-025-00622-7\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s13668-025-00622-7.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T12:56:52Z","timestamp":1739451412000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s13668-025-00622-7"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,13]]},"references-count":76,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2025,12]]}},"alternative-id":["622"],"URL":"https:\/\/doi.org\/10.1007\/s13668-025-00622-7","relation":{},"ISSN":["2161-3311"],"issn-type":[{"value":"2161-3311","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,13]]},"assertion":[{"value":"28 January 2025","order":1,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"13 February 2025","order":2,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Compliance with Ethical Standards"}},{"value":"RO received lectures\u2019 and consulting fees from W\u00f6rwag Pharma GmbH and P&G Health Germany. JG, KP, and EA have no conflict of interest to declare.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of Interest"}},{"value":"This article does not contain any studies with human or animal subjects performed by any of the authors.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Human and Animal Rights and Informed Consent"}}],"article-number":"32"}}