Prevalence of vitamin D insufficiency and associations between 25(OH)D concentrations and health outcomes in children aged 4 – 11 years in the north of Ireland

• Published in: Proceedings of the Nutrition Society 2024-11, Vol.83 (OCE4), Article E360
• Main Authors: Royle, Emily, McSorley, Emeir M., Kirsty Pourshahidi, L., Armstrong, David, Magee, Pamela J.
• Format: Article
• Language: English
• Subjects: 25-Hydroxyvitamin D; Calciferol; Children; Cognitive ability; Diet; Dietary intake; Food intake; Fortified foods; Grip strength; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Muscle strength; Parathyroid hormone; Parents; Rickets; Vitamin D; Winter
• ISSN: 0029-6651; 1475-2719
• DOI: 10.1017/S0029665124005986

Optimal vitamin D status is important for growth and development during childhood(1). Children with a circulating concentration of 25-hydroxyvitamin D [25(OH)D] below 25 nmol/L are at increased risk of rickets. In order to maintain 25(OH)D > 25nmol/L, a dietary intake of 10µg/d vitamin D is recommended for children aged 4 years and above(2,3). The aim of this study was to determine vitamin D status in healthy children and to investigate associations between 25(OH)D concentrations and muscle health, cognitive function, and parental knowledge of vitamin D, vitamin D habits, perceptions, and practices. A cross-sectional study of healthy children aged 4 – 11 years conducted between 2019 – 2023 examined vitamin D status by measuring plasma 25(OH)D via the gold standard liquid chromatography tandem mass spectrometry and parathyroid hormone concentrations. Muscle strength (hand grip and balance) was determined by dynamometer, single and tandem stance balancing whilst cognitive function was assessed using the Cambridge Neuropsychological Test Automated Battery. Parents completed questionnaires to assess vitamin D knowledge, and perceptions, habits, and attitude towards vitamin D. A total of 192 children (91 boys; 101 girls) with an average age of 8.2 years were recruited. Plasma 25(OH)D concentrations were 61.10 ± 18.75 nmol/L (n = 190), with 68.4% of children defined as vitamin D sufficient (25(OH)D>50nmol/L). When stratified by winter months, only 58% of children were vitamin D sufficient. In single linear regression, plasma 25(OH)D concentrations were positively associated with dominant hand grip strength, single leg balance and the cognitive test ‘5choice movement time’ (p