A Pilot Study to Evaluate the Effect of Vitamin D Supplementation on Insulin Secretion and Peripheral Insulin Sensitivity

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.The available trials have been conducted using small sample sizes in different subgroups (hemodialyzed patients , healthy volunteers , gestational diabetes and post menopausal women ) document variable results with a positive result in some (hemodialysis and gestational diabetes) and no effect in other settings(healthy volunteers and postmenopausal women).We therefore, planned this trial to study the effect of vitamin D supplementation (240,000 IU) on insulin secretion and peripheral insulin sensitivity.This will also help to calculate sample size for and choose an appropriate index for a larger randomized control trial which may be required subsequently.

Study design and comparison:Single group, open label intervention trial involving assessment of insulin sensitivity and secretion in 30 volunteers before and after 4weeks of a megadose of Vitamin D. The pre and post intervention results will be compared using the paired t test.