Role of vitamin D in Inflammatory bowel disease in children

Abstract

Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, is a chronic inflammatory disorder with an increasing incidence and prevalence among children worldwide. Micronutrient deficiencies are common in pediatric IBD, particularly deficiencies of iron, calcium, and vitamin D, due to reduced dietary intake, malabsorption, gastrointestinal losses, disease activity, and treatment-related factors. Vitamin D has important functions beyond bone health, including regulation of intestinal epithelial integrity, immune responses, and gut microbiota. In children with IBD, low serum 25-hydroxyvitamin D concentrations have been associated with impaired gut barrier function, increased inflammatory activity, and less favorable disease and treatment outcomes. Vitamin D sufficiency may contribute to reduced disease activity and may enhance response to anti-tumor necrosis factor therapy. Several factors can predispose children with IBD to hypovitaminosis D, including corticosteroid exposure, malnutrition, reduced sunlight exposure, disease activity, gastrointestinal involvement, seasonal variation, and altered body composition. Management includes identification of children at risk, dietary optimization, adequate sunlight exposure, and vitamin D supplementation when needed. However, considerable variation remains regarding definitions of deficiency, supplementation regimens, and optimal monitoring strategies. This review discusses the role of vitamin D in pediatric inflammatory bowel disease, with emphasis on its effects on gut health, disease activity, treatment outcomes, risk factors for deficiency, correction strategies, supplementation, and monitoring.