Effect of Vitamin D on Metabolic Profile in Overweight or Obese Women

• Change in Body Fat Mass [ Time Frame: 3 months minus baseline ] [ Designated as safety issue: Yes ]
  Body composition was assessed by Bioelectrical Impedance Analysis (model 4000; Body Stat Quad Scan, Douglas Isle of Man, British Isles).The principle of measuring the flow of current through the body is dependent on the frequency applied. At low frequencies, the current cannot bridge the cellular membrane and will pass predominantly through the extra-cellular space. At higher frequencies penetration of the cell membrane occurs and the current is conducted by both the extra-cellular water (ECW) and intra-cellular water (ICW).FFM can be estimated because FFM is primarily composed of water.
  
  
• Change in Glucose Concentrations [ Time Frame: 3 months minus baseline ] [ Designated as safety issue: Yes ]
  
• Change in Post Load Glucose Concentrations [ Time Frame: 3 months minus baseline ] [ Designated as safety issue: Yes ]
  It was performed 2 hours after 75g oral glucose tolerance test (75-OGTT).
  
  
• Change in Insulin Concentrations [ Time Frame: 3 months minus baseline ] [ Designated as safety issue: Yes ]
  

Vitamin D deficiency is a worldwide health problem and is determined as a risk factor in Cardiometabolic disorders including Cardiovascular disease, Metabolic syndrome, and type 2 diabetes mellitus. The investigators investigated the effect of vitamin D3 supplementation on metabolic profile in overweight or obese women.

A double blind randomized clinical trial was conducted in 77 premenopause overweight or obese women. Participants were classified into two groups : vitamin D supplementation [1000 IU/day as cholecalciferol tablets (n=39)] or placebo (n=38). Vein blood samples were taken after at least 12 hours overnight fasting. Selected anthropometric measures, blood pressure Lipids, lipoproteins and glycemic indices were measured at baseline and after 12 weeks. Body fat mass was determined using BIA. Also the investigators assessed dietary intake using 24 hours food recall and semi-quantitative food frequency and physical activity using IPAQ questionnaires.

The investigators conducted the study between October 2009 and March 2010 at the Medical school, Tehran, Iran. Recruitment began in October 2009 via advertisements and was terminated in October 2009. The investigators excluded patients with a history of Cardiovascular disease, Liver disease, Gastrointestinal disease, Kidney disease, diabetes mellitus, and Osteoporosis. Moreover, pregnancy, lactation, vegetarianism, and intake of dietary supplements were the exclusion criteria.