title: Effects of vitamin D supplementation on insulin resistance and cardiometabolic risk factors in children with metabolic syndrome: a triple-masked controlled trial.
abstract: OBJECTIVE
  This triple-masked controlled trial aimed to assess the effects of vitamin D supplementation on insulin resistance and cardiometabolic risk factors in obese children and adolescents.
  
  
  METHODS
  The study comprised 50 participants, aged 10 to 16 years, who were randomly assigned into two groups of equal number. In this 12-week trial, one group received oral vitamin D (300,000 IU) and the other group received placebo. Cardiometabolic risk factors, insulin resistance, and a continuous value of metabolic syndrome (cMetS) were determined. Statistical analysis was conducted after adjustment for covariate interactions.
  
  
  RESULTS
  Overall, 21 patients in the vitamin D group and 22 in the placebo group completed the trial. No significant difference was observed in the baseline characteristics of the two groups. After the trial, in the vitamin D group, serum insulin and triglyceride concentrations, as well as HOM -IR and C-MetS decreased significantly, both when compared with the baseline and with the placebo group. No significant difference was observed when comparing total cholesterol, LDL-C, HDL-C, fasting blood glucose, and blood pressure.
  
  
  CONCLUSIONS
  The present findings support the favorable effects of vitamin D supplementation on reducing insulin resistance and cardiometabolic risk factors in obese children.
authors.affiliation: Pediatrics Department, Child Growth and Development Research Center and Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran. Electronic address: kelishadi@med.mui.ac.ir.
authors.forename: Roya
authors.initials: R
authors.lastname: Kelishadi
authors.affiliation: Pediatrics Department, Child Growth and Development Research Center and Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Shadi
authors.initials: S
authors.lastname: Salek
authors.affiliation: Pediatrics Department, Child Growth and Development Research Center and Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Salek
authors.affiliation: Pediatrics Department, Child Growth and Development Research Center and Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mahin
authors.initials: M
authors.lastname: Hashemipour
authors.affiliation: Department of English Linguistics, University of Isfahan, Isfahan, Iran.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Movahedian
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D002784:Cholesterol / Q000097:blood; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000188:drug therapy; D009765:Obesity / Q000097:blood*; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood; D014807:Vitamin D / Q000008:administration & dosage* / Q000097:blood*; D014815:Vitamins / Q000008:administration & dosage*
chemical_list: D007328:Insulin; D014280:Triglycerides; D014815:Vitamins; D014807:Vitamin D; D002784:Cholesterol
keywords: Children and adolescents; Crianças e adolescentes; Insulin resistance; Metabolic syndrome; Resistência à insulina; Síndrome metabólica; Vitamin D; Vitamina D