{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T06:07:58Z","timestamp":1789884478367,"version":"4.0.1"},"reference-count":36,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,5,23]],"date-time":"2024-05-23T00:00:00Z","timestamp":1716422400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"\u201cVictor Babes\u201d, University of Medicine and Pharmacy"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Recent studies hypothesized that vitamin D supplementation and subsequent higher 25(OH)D serum levels could protect against respiratory infections in children. This cross-sectional study, conducted from May 2022 to December 2023 in Timisoara, Romania, aimed to evaluate the potential influence of vitamin D supplementation on the incidence of respiratory infections among preschool-age children. This study examined 215 children over 18 months who were split into a group of patients with recurrent respiratory infections (n = 141) and another group of patients with only one respiratory tract infection in the past 12 months (n = 74). Patients were evaluated based on their serum vitamin D levels 25(OH)D, demographic characteristics, and health outcomes. The study identified that preschool-age children with recurrent infections had significantly lower mean vitamin D concentrations (24.5 ng\/mL) compared to the control group (29.7 ng\/mL, p &lt; 0.001). Additionally, a higher proportion of vitamin D deficiency was observed among children with recurrent infections in the past 12 months. Notably, vitamin D supplementation above 600 IU\/week significantly reduced the likelihood of respiratory infections, evidenced by an odds ratio of 0.523 (p &lt; 0.001), indicating that preschool-age children receiving a dose of vitamin D higher than 600 IU\/week were about half as likely to experience respiratory infections compared to those who did not. Furthermore, no significant associations were found between sun exposure, daily sunscreen use, and the incidence of respiratory infections. Conclusively, this study underscores the potential role of vitamin D in helping the immune system against respiratory infections in preschool-age children. The observed protective effect of vitamin D supplementation suggests a potential public health strategy to mitigate the incidence of respiratory infections in preschool children on top of the already known benefits.<\/jats:p>","DOI":"10.3390\/nu16111595","type":"journal-article","created":{"date-parts":[[2024,5,23]],"date-time":"2024-05-23T11:37:13Z","timestamp":1716464233000},"page":"1595","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Exploring the Preventive Potential of Vitamin D against Respiratory Infections in Preschool-Age Children: A Cross-Sectional Study"],"prefix":"10.3390","volume":"16","author":[{"given":"Oana Silvana","family":"Sarau","sequence":"first","affiliation":[{"name":"Department V, Internal Medicine, Discipline of Hematology, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"},{"name":"Doctoral School, \u2018\u2019Victor Babes\u2019\u2019 University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hari Charan","family":"Rachabattuni","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Dr. Y.S.R. University of Health Sciences, Vijayawada 520008, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-7800-7666","authenticated-orcid":false,"given":"Sai Teja","family":"Gadde","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, All India Institute of Medical Sciences (AIIMS), Mangalagiri 522503, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6789-583X","authenticated-orcid":false,"given":"Sai Praveen","family":"Daruvuri","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Bukovinian State Medical University, Teatralna Square, 2, 58002 Chernivtsi, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Larisa Mihaela","family":"Marusca","sequence":"additional","affiliation":[{"name":"Doctoral School, \u2018\u2019Victor Babes\u2019\u2019 University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"},{"name":"Laboratory Medicine, \u201cLouis Turcanu\u201d Emergency Hospital for Children, Doctor Iosif Nemoianu Street, 300011 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6133-0204","authenticated-orcid":false,"given":"Florin George","family":"Horhat","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Multidisciplinary Research Center on Antimicrobial Resistance (MULTI-REZ), \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ariadna Petronela","family":"Fildan","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, Faculty of Medicine, \u201cOvidius\u201d University of Constanta, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Tanase","sequence":"additional","affiliation":[{"name":"Doctoral School, \u2018\u2019Victor Babes\u2019\u2019 University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4348-5469","authenticated-orcid":false,"given":"Catalin","family":"Prodan-Barbulescu","sequence":"additional","affiliation":[{"name":"Doctoral School, \u2018\u2019Victor Babes\u2019\u2019 University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"},{"name":"Department of Anatomy and Embryology, Discipline of Pulmonology, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"},{"name":"IInd Surgery Clinic, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7210-1263","authenticated-orcid":false,"given":"Delia Ioana","family":"Horhat","sequence":"additional","affiliation":[{"name":"Department of Ear-Nose-Throat, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,23]]},"reference":[{"key":"ref_1","unstructured":"Sizar, O., Khare, S., Goyal, A., and Givler, A. 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