Background: Vitamin D deficiency can have significant health implications for children and adolescents, affecting bone development, immune function, and overall well-being. We aimed to investigate the prevalence of vitamin D deficiency and its associated factors in Iranian children and adolescents.
Materials and Methods: In this systematic review, a search of online databases (Medline, Scopus, Web of Science, WHO, CIVILICA, and Google Scholar) was conducted with no time limit up to March 2024. The quality of the information was evaluated using the STROBE checklist.
Results: Finally, 33 related studies were included. The prevalence of vitamin D deficiency in children and adolescents was estimated to be 47.35% (3-91.7%), with a mean value ranging from 7.26 ± 2.81 to 23.46 ± 9.30 ng/dL. The prevalence of vitamin D insufficiency in children and adolescents was estimated to be 55.6% (11.3-100%). The prevalence of vitamin D deficiency in infants was estimated to be 51% (2.8-93.3%), with a mean value ranging from 28.3 ± 19.4 to 61.3 ± 31.4 ng/dL. The prevalence of severe vitamin D deficiency was significantly higher among girls than boys. The concentration of 25(OH)D was associated with BMI (p = 0.000, r = -0.13), pubertal status (r = -0.08, p= 0.04), weight (p = 0.000, r = -0.12), waist circumference (r = -0.112, p = 0.047), age (p = 0.000, r= -0.13), height (p < 0.05), pubertal status (r=− 0·08, p=0·04), sunlight exposure (r = 0.10, p = 0.04), gender (p = 0.01), maternal vitamin D deficiency (p < 0.01), daily intake of vitamin D (p < 0.05), and the areas (p < 0.05).
Conclusion: The prevalence of vitamin D deficiency among Iranian children and adolescents is alarmingly high, with various studies indicating significant rates across different age groups, genders, and regions. This deficiency poses serious health risks, necessitating urgent public health interventions.