{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T01:35:32Z","timestamp":1788917732510,"version":"build-2803163510"},"reference-count":60,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2023,10,27]],"date-time":"2023-10-27T00:00:00Z","timestamp":1698364800000},"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>The level of association between 25-hydroxyvitamin D (25[OH]D) levels and students\u2019 academic performance has not yet been established. The current study aimed to investigate the association between serum 25(OH)D levels and academic performance among schoolchildren in Sudan. A cross-sectional study was conducted among schoolchildren during the 2021\/2022 academic year from four randomly selected schools in Almatamah, River Nile State, northern Sudan. Sociodemographic data were collected using a questionnaire. Anthropometric measurements were performed in accordance with standard procedures. Academic performance was obtained from school records. Serum 25(OH)D levels were measured, and regression (multiple linear regression and multivariate logistic) analyses were performed. A total of 241 participants were enrolled in this study, of whom 129 (53.5%) were female. The mean standard deviation (SD) of the participants\u2019 ages was 15 \u00b1 1.6 years. In multiple linear regression tests, being female, age, employment, and serum 25(OH)D level were positively associated with academic performance. The average overall academic score was 33.74%. Of the 241 participants, 95 (39.4%) and 149 (61.6%) had good and poor academic performances, respectively. In multivariable logistic regressions, age and 25(OH)D level were inversely associated with poor academic performance and vitamin D deficiency was associated with poor performance. The current study revealed a positive association between 25(OH)D levels and adolescents\u2019 academic performance. Effective interventional programs are needed to maintain sufficient vitamin D levels during childhood and adolescence and, as a consequence, to improve academic performance.<\/jats:p>","DOI":"10.3390\/nu15214552","type":"journal-article","created":{"date-parts":[[2023,10,27]],"date-time":"2023-10-27T09:56:36Z","timestamp":1698400596000},"page":"4552","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Association between Serum 25-Hydroxyvitamin D Concentrations and Academic Performance among Adolescent Schoolchildren: A Cross-Sectional Study"],"prefix":"10.3390","volume":"15","author":[{"given":"Ahmed A.","family":"Hassan","sequence":"first","affiliation":[{"name":"Faculty of Medicine, University of Khartoum, Khartoum 11115, Sudan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mustafa I.","family":"Elbashir","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Khartoum, Khartoum 11115, Sudan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah","family":"Al-Nafeesah","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Unaizah College of Medicine and Medical Sciences, Qassim University, Unaizah 51911, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5918-2246","authenticated-orcid":false,"given":"Ashwaq","family":"AlEed","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Unaizah College of Medicine and Medical Sciences, Qassim University, Unaizah 51911, Saudi Arabia"},{"name":"Department of Pediatrics, College of Medicine, Qassim University, Buraydah 52571, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5031-7741","authenticated-orcid":false,"given":"Ishag","family":"Adam","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Unaizah College of Medicine and Medical Sciences, Qassim University, Unaizah 51911, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1136\/jech-2017-209605","article-title":"How adolescent health influences education and employment: Investigating longitudinal associations and mechanisms","volume":"72","author":"Hale","year":"2018","journal-title":"J. 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