{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T15:41:01Z","timestamp":1779291661269,"version":"3.51.4"},"reference-count":21,"publisher":"Springer Science and Business Media LLC","issue":"4","license":[{"start":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T00:00:00Z","timestamp":1773792000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"},{"start":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T00:00:00Z","timestamp":1773792000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Eur J Pediatr"],"DOI":"10.1007\/s00431-026-06858-x","type":"journal-article","created":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T10:36:18Z","timestamp":1773830178000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Investigating vitamin B12 levels in children with obesity: the role of metformin"],"prefix":"10.1007","volume":"185","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-4000-6891","authenticated-orcid":false,"given":"A.","family":"Iwa\u0144ska","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9362-8187","authenticated-orcid":false,"given":"D.","family":"Goncerz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"M.","family":"Ahmed","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"R.","family":"Aoun","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4770-5641","authenticated-orcid":false,"given":"A.","family":"Kozio\u0142-Kozakowska","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1247-5121","authenticated-orcid":false,"given":"E.","family":"Szczudlik","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2743-9625","authenticated-orcid":false,"given":"A.","family":"St\u0119pniewska","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3889-1913","authenticated-orcid":false,"given":"M.","family":"W\u00f3jcik","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4086-6525","authenticated-orcid":false,"given":"J. B.","family":"Starzyk","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,3,18]]},"reference":[{"issue":"23","key":"6858_CR1","doi-asserted-by":"publisher","first-page":"16588","DOI":"10.3390\/ijms242316588","volume":"24","author":"A Aureli","year":"2023","unstructured":"Aureli A, Recupero R, Mariani M et al (2023) Low levels of serum total vitamin B12 are associated with worse metabolic phenotype in a large population of children, adolescents and young adults, from underweight to severe obesity. Int J Mol Sci 24(23):16588. https:\/\/doi.org\/10.3390\/ijms242316588","journal-title":"Int J Mol Sci"},{"key":"6858_CR2","doi-asserted-by":"publisher","first-page":"100087","DOI":"10.1016\/j.obpill.2023.100087","volume":"8","author":"M Bradley","year":"2023","unstructured":"Bradley M, Melchor J, Carr R, Karjoo S (2023) Obesity and malnutrition in children and adults: a clinical review. Obesity Pillars 8:100087. https:\/\/doi.org\/10.1016\/j.obpill.2023.100087","journal-title":"Obesity Pillars"},{"key":"6858_CR3","doi-asserted-by":"publisher","DOI":"10.15761\/CRT.1000335","author":"S Butala","year":"2021","unstructured":"Butala S, Teresczuk M (2021) Should We Worry About Elevated B12 Levels in Children? Oat. https:\/\/doi.org\/10.15761\/CRT.1000335","journal-title":"Oat"},{"issue":"12","key":"6858_CR4","doi-asserted-by":"publisher","first-page":"844","DOI":"10.1038\/s41371-024-00955-w","volume":"38","author":"X Liang","year":"2024","unstructured":"Liang X, Huang D, Bi Y, He Y, Mao T, Liu Q, Hu G, Tong J, Chen L, Wang Y, An X, Jiang X, Tahir MF (2024) The impact of folic acid\/VB12 deficiency on essential hypertension in children and adolescents: from a nested case-control and a cohort study. J Hum Hypertens 38(12):844\u2013850. https:\/\/doi.org\/10.1038\/s41371-024-00955-w","journal-title":"J Hum Hypertens"},{"issue":"11","key":"6858_CR5","first-page":"1648","volume":"67","author":"S Ozer","year":"2017","unstructured":"Ozer S, Sonmezgoz E, Demir O (2017) Negative Correlation Among Vitamin B12 Levels, Obesity Severity and Metabolic Syndrome in Obese Children: A Case-Control Study. J Pak Med Assoc 67(11):1648\u20131653","journal-title":"J Pak Med Assoc"},{"issue":"3","key":"6858_CR6","doi-asserted-by":"publisher","first-page":"242","DOI":"10.3967\/bes2024.028","volume":"37","author":"QR Zhu","year":"2024","unstructured":"Zhu QR, Kok ED, Bekele HT et al (2024) Association of Serum Folate and Vitamin B12 Concentrations with Obesity in Chinese Children and Adolescents. Biomed Environ Sci 37(3):242\u2013253. https:\/\/doi.org\/10.3967\/bes2024.028","journal-title":"Biomed Environ Sci"},{"issue":"12","key":"6858_CR7","doi-asserted-by":"publisher","first-page":"2027","DOI":"10.3945\/jn.114.201202","volume":"144","author":"IR Gunanti","year":"2014","unstructured":"Gunanti IR, Marks GC, Al-Mamun A, Long KZ (2014) Low serum vitamin B-12 and folate concentrations and low thiamin and riboflavin intakes are inversely associated with greater adiposity in Mexican American children. J Nutr 144(12):2027\u20132033. https:\/\/doi.org\/10.3945\/jn.114.201202","journal-title":"J Nutr"},{"issue":"4","key":"6858_CR8","doi-asserted-by":"publisher","first-page":"319","DOI":"10.1177\/10815589231225180","volume":"72","author":"MS Demirtas","year":"2024","unstructured":"Demirtas MS, Kilicaslan C, Erdal H (2024) Evaluation of vitamin B12 levels among severe obese and obese adolescents. J Invest Med 72(4):319\u2013325. https:\/\/doi.org\/10.1177\/10815589231225180","journal-title":"J Invest Med"},{"issue":"2","key":"6858_CR9","doi-asserted-by":"publisher","first-page":"155","DOI":"10.4274\/jcp.2023.36450","volume":"21","author":"\u00d6 Akbulut","year":"2023","unstructured":"Akbulut \u00d6, Apak FBB, \u015een\u00e7elikel T (2023) Evaluation of increased vitamin B12 levels in children: is it clinically significant? G\u00fcncel Pediatri 21(2):155\u2013161. https:\/\/doi.org\/10.4274\/jcp.2023.36450","journal-title":"G\u00fcncel Pediatri"},{"issue":"2","key":"6858_CR10","doi-asserted-by":"publisher","first-page":"127","DOI":"10.4274\/jcp.2023.75688","volume":"21","author":"\u0130 S\u00fcr\u00fcc\u00fc Kara","year":"2023","unstructured":"S\u00fcr\u00fcc\u00fc Kara \u0130, Ayd\u0131n Peker N, Dol\u011fun \u0130, Merto\u011flu C (2023) Vitamin B12 level in children. G\u00fcncel Pediatri 21(2):127\u2013134. https:\/\/doi.org\/10.4274\/jcp.2023.75688","journal-title":"G\u00fcncel Pediatri"},{"key":"6858_CR11","doi-asserted-by":"publisher","DOI":"10.1016\/j.anpede.2022.04.011","author":"J \u00c1lvareza","year":"2022","unstructured":"\u00c1lvareza J, Aguilara F, Lurbe E (2022) Blood pressure measurement in children and adolescents: key element in the evaluation of arterial hypertension. Ann Pediatr. https:\/\/doi.org\/10.1016\/j.anpede.2022.04.011","journal-title":"Ann Pediatr"},{"key":"6858_CR12","unstructured":"StatSoft, Inc (2013) STATISTICA (Version 13.0) [Computer software]. StatSoft, Inc. https:\/\/www.statsoft.com"},{"issue":"9","key":"6858_CR13","doi-asserted-by":"publisher","first-page":"933","DOI":"10.1001\/archpedi.160.9.933","volume":"160","author":"O Pinhas-Hamiel","year":"2006","unstructured":"Pinhas-Hamiel O, Doron-Panush N, Reichman B, Nitzan-Kaluski D, Shalitin S, Geva-Lerner L (2006) Obese children and adolescents: a risk group for low vitamin B12 concentration. Arch Pediatr Adolesc Med 160(9):933\u2013936. https:\/\/doi.org\/10.1001\/archpedi.160.9.933","journal-title":"Arch Pediatr Adolesc Med"},{"key":"6858_CR14","unstructured":"Angelini A, Cappuccilli ML, Magnoni G, Croci Chiocchini AL, Aiello V, Napoletano A, Iacovella F, Troiano A, Mancini R, Capelli I, Cianciolo G (2021) The link between homocysteine, folic acid and vitamin B12 in chronic kidney disease. G Ital Nefrol 38(4):2021-vol4"},{"issue":"1","key":"6858_CR15","doi-asserted-by":"publisher","first-page":"84","DOI":"10.14744\/hnhj.2018.19970","volume":"59","author":"F Dursun","year":"2019","unstructured":"Dursun F, Gerenli N (2019) Relationship between insulin resistance and vitamin B12 deficiency in obese children. Haydarpasa Numune Med J 59(1):84\u201387. https:\/\/doi.org\/10.14744\/hnhj.2018.19970","journal-title":"Haydarpasa Numune Med J"},{"issue":"2","key":"6858_CR16","doi-asserted-by":"publisher","first-page":"134","DOI":"10.5114\/pedm.2021.107166","volume":"27","author":"\u0141 Cwynar-Zaj\u0105c","year":"2021","unstructured":"Cwynar-Zaj\u0105c \u0141 (2021) Metformin \u2013 a new approach. Pediatr Endocrinol Diabetes Metab 27(2):134\u2013140. https:\/\/doi.org\/10.5114\/pedm.2021.107166","journal-title":"Pediatr Endocrinol Diabetes Metab"},{"issue":"3","key":"6858_CR17","doi-asserted-by":"publisher","first-page":"223","DOI":"10.6065\/apem.2142210.105","volume":"27","author":"YM Yu","year":"2022","unstructured":"Yu YM, So SKC, Khallouq BB (2022) The effect of metformin on vitamin B12 level in pediatric patients. Ann Pediatr Endocrinol Metab 27(3):223\u2013228. https:\/\/doi.org\/10.6065\/apem.2142210.105","journal-title":"Ann Pediatr Endocrinol Metab"},{"key":"6858_CR18","unstructured":"Yordanova D, Todorova Z, Dimitrova-Mladenova M, Stefanova E (2019) Vitamin B12 levels in children after metformin treatment [abstract]. Fat, Metabolism and Obesity. 58th Annual ESPE Meeting (ESPE 2019), Vienna. Available at: https:\/\/abstracts.eurospe.org\/hrp\/0092\/hrp0092p3-108. Accessed 16 Mar 2026"},{"issue":"3","key":"6858_CR19","doi-asserted-by":"publisher","first-page":"e243","DOI":"10.1016\/S2542-5196(21)00352-1","volume":"6","author":"V Miller","year":"2022","unstructured":"Miller V, Reedy J, Cudhea F, Zhang J, Shi P, Erndt-Marino J, Coates J, Micha R, Webb P, Mozaffarian D, Global Dietary Database (2022) Global, regional, and national consumption of animal-source foods between 1990 and 2018: findings from the Global Dietary Database. Lancet Planet Health 6(3):e243\u2013e256. https:\/\/doi.org\/10.1016\/S2542-5196(21)00352-1","journal-title":"Lancet Planet Health"},{"key":"6858_CR20","unstructured":"WHO European Regional Obesity Report (2022) WHO Regional Office for Europe, Copenhagen"},{"key":"6858_CR21","unstructured":"Mazur A, Zachurzok A, Baran J, Dere\u0144 K, \u0141uszczki E, Weres A, Wyszy\u0144ska J, Dylczyk J, Szczudlik E, Dro\u017cd\u017c D, Metelska P, Brzezi\u0144ski M, Kozio\u0142-Kozakowska A, Matusik P, Socha P, Olszanecka-Glinianowicz M, Jackowska T, Walczak M, Peregud-Pogorzelski J, Tomiak E, W\u00f3jcik M (2023) Oty\u0142o\u015b\u0107 dzieci\u0119ca. Stanowisko Polskiego Towarzystwa Pediatrycznego, Polskiego Towarzystwa Oty\u0142o\u015bci Dzieci\u0119cej, Polskiego Towarzystwa Endokrynologii i Diabetologii Dzieci\u0119cej, Kolegium Lekarzy Rodzinnych w Polsce oraz Polskiego Towarzystwa Bada\u0144 nad Oty\u0142o\u015bci\u0105. Med Prakt Pediatria wyd specj 1\/2023:1\u201343"}],"container-title":["European Journal of Pediatrics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00431-026-06858-x.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00431-026-06858-x","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00431-026-06858-x.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T07:54:23Z","timestamp":1776930863000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00431-026-06858-x"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,18]]},"references-count":21,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["6858"],"URL":"https:\/\/doi.org\/10.1007\/s00431-026-06858-x","relation":{},"ISSN":["1432-1076"],"issn-type":[{"value":"1432-1076","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,18]]},"assertion":[{"value":"31 October 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"27 February 2026","order":2,"name":"revised","label":"Revised","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"10 March 2026","order":3,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"18 March 2026","order":4,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"189"}}