Contemporary perspectives on vitamin D provision in children and adolescents with obesity: a literature review and clinical case description
Authors:   Danylo Halytsky Lviv National Medical University, Yatsula M. , Nyankovskyy S. ,   Danylo Halytsky Lviv National Medical University
Published: January 2024

Introduction. Vitamin D deficiency is currently considered a global epidemic. Recent data highlight its pivotal role in the development of metabolic disorders, including obesity in children and adolescents. The aim of the study. To review current literature on the problem of vitamin D provision in children and adolescents with obesity, and to present a clinical case of a child with obesity, vitamin D deficiency, and accompanying metabolic disorders. Materials and methods: The study included literary review using content analysis, systemic and comparative analysis methods, as well as biblio-semantic methods to explore current data on the problem of vitamin D provision in children and adolescents with obesity. Sources included PubMed-NCBI, Medline, CochraneLibrary, EMBASE, ResearchGate databases using keywords as follows: children, adolescents, insulin resistance, obesity, vitamin D deficiency, VDR (Vitamin D Receptor) gene polymorphism, leptin, adipocytes. 66 English-language articles were analyzed, highlighting the role of vitamin D in human metabolic processes, its association with obesity, mechanisms of its deficiency impact including the inhibitory effect of leptin and interleukin 6, and the peculiarities of vitamin D biological action through nuclear VDR-mediated control of target genes. The prevalence of vitamin D deficiency in obese children in various countries was determined. Results. Obesity can induce altered protein binding and accelerated metabolic clearance of 25(OH)D, leading to reduced levels of 25(OH)D in the blood serum. It was identified that lower serum vitamin D levels and VDR gene polymorphism are associated with a predisposition to obesity in children and its severe consequences, this link apparently can help to identify VDR features that predict an increased risk of developing obesity, potentially leading to new therapeutic strategies for this metabolic condition. This will also increase public awareness about the psychosocial and clinical consequences of vitamin D deficiency and VDR gene polymorphism in obese children. Children with excessive weight and obesity are often diagnosed with hypovitaminosis, including vitamin D deficiency. Many studies around the world have found that vitamin D deficiency in obese children is at a critical stage and requires a change in diagnostic and treatment strategies. The clinical case described involves a patient who had obesity in association with vitamin D deficiency, and characteristic biochemical changes typical of this pathology. Biochemical indices included vitamin D deficiency, dyslipidemia, insulin resistance, leptin resistance, and hypothyroidism. Bioimpedance analysis revealed the presence of excessive body fat and its abnormal abdominal distribution in the child. Conclusions. Currently vitamin D deficiency is considered a global epidemic, causing concern among physicians and researchers of various specialties. Recent data underscore its leading role in the onset of metabolic disorders, including obesity in children and adolescents. The literature review confirmed the significant impact of vitamin D on the primary biochemical and metabolic processes in the human body, its crucial role in the emergence of obesity and various complications in children and adolescents. The presence of overweight or obesity in these patients requires a number of laboratory indeces, including serum vitamin D, leptin and thyroid hormones levels, protein, carbohydrate and lipid metabolism parameters, to be estimated. The use of bioimpedance analysis and ultrasound examination of the thyroid gland is advisable.