title: Efficacy of supplementary vitamin D on improvement of glycemic parameters in patients with type 2 diabetes mellitus; a randomized double blind clinical trial.
abstract: BACKGROUND
  Studies have revealed the association between vitamin D deficiency and changes in blood glucose and insulin levels as well as sensitivity of the target tissues to insulin.
  
  
  OBJECTIVE
  In this study, we examined the effect of adding vitamin D (cholecalciferol ; 50,000 units) to therapeutic regimen of T2DM patients compared to placebo on regulating the blood glucose and glycemic parameters.
  
  
  METHODS
  This study was a double blind clinical trial conducted on 60 type 2 diabetes mellitus (T2DM) patients. Exclusion criteria were taking calcium, vitamin D supplements or any drugs effecting calcium and vitamin D metabolism in the past 6 months. Serum 25-Hydroxy vitamin D [25(OH)D] level was measured with ELISA method. Patients were administered weekly vitamin D supplementation (50000 units) for 12 weeks.
  
  
  RESULTS
  There was no significant relation between HbA1c and 25(OH)D level prior the study (p> 0.05). After intervention, 25(OH)D level in interventional group was significantly higher compared to that of control group. HbA1c in male interventional group was significantly less than that of control group (p= 0.0068).
  
  
  CONCLUSIONS
  Weekly vitamin D supplementation had beneficial effect on glycemic parameters in male type 2 diabetic patients.
authors.affiliation: Department of Nephrology, Division of Nephropathology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Nasri
authors.affiliation: Department of Internal Medicine, Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Behradmanesh
authors.affiliation: Department of Internal Medicine, Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Ahmad Reza
authors.initials: AR
authors.lastname: Maghsoudi
authors.affiliation: Department of Epidemiology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Ahmadi
authors.affiliation: Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Parto
authors.initials: P
authors.lastname: Nasri
authors.affiliation: Medical Plants Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Rafieian-Kopaei
keywords: HbA1c; Type 2 diabetes patients; Vitamin D