{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T01:15:47Z","timestamp":1775178947545,"version":"3.50.1"},"reference-count":16,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2014,12,4]],"date-time":"2014-12-04T00:00:00Z","timestamp":1417651200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Emerging evidence indicates an association between obesity, metformin use  and reduced vitamin B12 status, which can have serious hematologic, neurologic and psychiatric consequences. This study aimed to examine B12 status in obese adolescents with pre-diabetes and\/or clinical features of insulin resistance. Serum B12 was measured using chemiluminescence immunoassay in 103 (43 male, 60 female) obese (mean body mass index (BMI) z-score \u00b1 SD (2.36 \u00b1 0.29)), adolescents aged 10 to 17 years, median (range) insulin sensitivity index of 1.27 (0.27 to 3.38) and 13.6% had pre-diabetes. Low B12  (&lt;148 pmol\/L) was identified in eight (7.8%) and borderline status (148 to 221 pmol\/L) in an additional 25 (24.3%) adolescents. Adolescents with borderline B12 concentrations had higher BMI z-scores compared to those with normal concentrations (2.50 \u00b1 0.22 vs. 2.32 \u00b1 0.30, p = 0.008) or those with low B12 concentration (2.50 \u00b1 0.22 vs. 2.27 \u00b1 0.226,  p = 0.041). In conclusion, nearly a third of obese adolescents with clinical insulin resistance had a low or borderline serum B12 status. Therefore, further investigations are warranted to explore the cause and the impact of low B12 status in obese pediatric populations.<\/jats:p>","DOI":"10.3390\/nu6125611","type":"journal-article","created":{"date-parts":[[2014,12,4]],"date-time":"2014-12-04T11:37:11Z","timestamp":1417693031000},"page":"5611-5618","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["Vitamin B12 in Obese Adolescents with Clinical Features of Insulin Resistance"],"prefix":"10.3390","volume":"6","author":[{"given":"Mandy","family":"Ho","sequence":"first","affiliation":[{"name":"Institute of Endocrinology and Diabetes, the Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW 2145, Australia"},{"name":"The Children's Hospital at Westmead Clinical School, University of Sydney, Locked Bag 4001, Westmead, NSW 2145, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jocelyn","family":"Halim","sequence":"additional","affiliation":[{"name":"Institute of Endocrinology and Diabetes, the Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW 2145, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Megan","family":"Gow","sequence":"additional","affiliation":[{"name":"Institute of Endocrinology and Diabetes, the Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW 2145, Australia"},{"name":"The Children's Hospital at Westmead Clinical School, University of Sydney, Locked Bag 4001, Westmead, NSW 2145, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nouhad","family":"El-Haddad","sequence":"additional","affiliation":[{"name":"Centre for Primary Health Care and Equity, University of New South Wales, Sydney, NSW 2052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teresa","family":"Marzulli","sequence":"additional","affiliation":[{"name":"Department of Haematology, The Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW 2145, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Louise","family":"Baur","sequence":"additional","affiliation":[{"name":"The Children's Hospital at Westmead Clinical School, University of Sydney, Locked Bag 4001, Westmead, NSW 2145, Australia"},{"name":"Kids Research Institute, the Children's Hospital at Westmead, Locked Bag 4001, Westmead,  NSW 2145, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chris","family":"Cowell","sequence":"additional","affiliation":[{"name":"Institute of Endocrinology and Diabetes, the Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW 2145, Australia"},{"name":"The Children's Hospital at Westmead Clinical School, University of Sydney, Locked Bag 4001, Westmead, NSW 2145, Australia"},{"name":"Kids Research Institute, the Children's Hospital at Westmead, Locked Bag 4001, Westmead,  NSW 2145, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7552-0789","authenticated-orcid":false,"given":"Sarah","family":"Garnett","sequence":"additional","affiliation":[{"name":"Institute of Endocrinology and Diabetes, the Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW 2145, Australia"},{"name":"The Children's Hospital at Westmead Clinical School, University of Sydney, Locked Bag 4001, Westmead, NSW 2145, Australia"},{"name":"Kids Research Institute, the Children's Hospital at Westmead, Locked Bag 4001, Westmead,  NSW 2145, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1056\/NEJMcp1113996","article-title":"Vitamin B12 deficiency","volume":"368","author":"Stabler","year":"2013","journal-title":"N. 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