A Trial to Study the Effect of Vitamin D Supplementation on Glucose and Insulin Metabolism in Centrally Obese Men

A Double Blind Randomized Control Trial to Study the Effect of Vitamin D Supplementation on Peripheral Insulin Sensitivity in Centrally Obese Men

The purpose of the study is to evaluate the change in glucose and insulin metabolism(early markers for development of diabetes) after 6 weeks of weekly Vitamin D supplementation. As vitamin D has been reported to be associated with lipid levels, CRP and blood pressure , we will also be measuring the changes in these variables.

Accumulating evidence suggests that serum Vitamin D levels may be inversely related to the prevalence of diabetes, to the concentration of glucose , insulin resistance and metabolic syndrome.These results have been replicated in patients at risk for diabetes with documentation of impairment in insulin secretion in Vitamin D deficient subjects. Therefore, vitamin D could be implicated in the pathogenesis of type 2 diabetes, by affecting either insulin sensitivity or ß cell function, or both. However, there is paucity of literature on the effect of Vitamin D supplementation on insulin resistance or glucose metabolism. As vitamin D has been reported to be associated with lipid levels, CRP and blood pressure , we will also be measuring the changes in these variables.

Inclusion Criteria:

• Male
• ≥35 years of age
• Waist circumference ≥78 cm

Exclusion Criteria:

• Diabetic- Fasting Blood Sugar >126 mg/dl or on anti-diabetic medication
• BP>140/90 or on anti-hypertensive medication
• Receiving Vitamin D or calcium supplementation
• Chronic disease-renal/hepatic/malignancy/gastrointestinal
• On any medication within the last one month which could potentially influence insulin secretion, insulin sensitivity, Vitamin D or Calcium metabolism
• Febrile illness or infective morbidity in the past 10 days
• Past history of nephrolithiasis