Background It is known that obesity is associated with vitamin D deficiency and observational studies have shown vitamin D deficiency to be linked with the development of type 2 diabetes. There are no comprehensive data regarding vitamin D deficiency in children with obesity in Sri Lanka and the objective of the study was to assess the prevalence of Vitamin D deficiency and its association with metabolic derangements among children with obesity. Methodology Two hundred and two children between 5 and 15 years of age attending the obesity clinic Lady Ridgeway Hospital (LRH) were recruited excluding those having possible secondary causes for obesity. Blood was drawn after 12-h overnight fast for fasting blood glucose(FBG), lipid profile, serum insulin, alanine aminotransferase (ALT),aspartate aminotransferase(AST), Vitamin D, parathyroid hormone(PTH),high sensitivity C reactive protein(hs-CRP). Oral glucose tolerance test (OGTT) was done with 2 h random blood glucose. Anthropometry, blood pressure were measured, and body fat mass was assessed using bio-impedance. Results Vitamin D deficiency (< 20 ng/ml) was seen in 152(75.2%) children and 43(21.3%) had insufficient (20-30 ng/ml) levels. Skin fold thickness, fasting and post-glucose insulin, HOMA-IR, PTH, LDL, Serum cholesterol and hs-CRP showed statistically significant negative correlations with Vitamin D levels. Conclusions Vitamin D deficiency was significantly high in Sri Lankan children with obesity and showed significant negative correlations with indicators of insulin resistance and adiposity.

Background: Micronutrient deficiencies are identified among obese individuals. Vitamin D deficiency (VDD) is prevalent in obese children, and is hypothesized to cause insulin resistance and metabolic abnormalities. This study aimed to determine the effect of vitamin D supplementation on obesity and related metabolic abnormalities among obese Sri Lankan children with VDD. Methods: A triple-blind randomized controlled trial was conducted among vitamin D deficient (< 20 ng/ml), obese children (n = 96), randomly allocated to three intervention arms-treatment arm receiving weekly vitamin D 2 50,000 IU; supplementation arm receiving 2500 IU weekly and control arm, receiving placebo. Anthropometry, percentage fat mass (%FM) and blood pressure were assessed and fasting blood glucose, fasting insulin, lipid profile, aspartate transaminase (ALT), alanine transaminase (AST), vitamin D, parathyroid hormone (PTH) and hs-CRP and OGTT with 2-h random blood glucose and insulin was performed at baseline and after 24 weeks of treatment. Ethics Review Committee of Faculty of Medicine, University of Colombo approved the protocol. Results: Waist circumference Z-score, %FM and serum calcium significantly improved across all three arms, ALT significantly improved in treatment and supplementation arms while, BMI Z-score, PTH and vitamin D significantly improved in the treatment arm. Biceps (p = 0.035) and subscapular (0.048) skin fold thickness, vitamin D (p = 0.004) and ALT (p = 0.012) significantly improved in the treatment arm. Conclusions: A strict dietary and physical activity regimen could improve some of the anthropometric, body composition and metabolic profiles, but high dose vitamin D, enhances those improvements. Therefore high dose vitamin D seems to potentiate management outcomes of obese children with vitamin D deficiency.