Vitamin D for glycemic control
How does vitamin D3 improve glycemic control (type 2 diabetes), and how much of what type vitamin D should be taken? PAUL STEPHAN, MD, Scarborough, ON
There’s evidence to suggest that vitamin D3 is important in the prevention of islet cell death. Vitamin D is required for the production of insulin, and improves insulin sensitivity. To date, there have been no large, well-designed, randomized controlled trials using vitamin D to improve glycemic control in type 2 diabetes, but a number of smaller studies, case series, and animal models suggest a potential benefit from vitamin D therapy. Replacement should be with vitamin D3, and doses should be titrated to the mid-normal range. Surveillance for hypercalcemia is essential when using high doses (e.g. > 2,000 IU per day) to treat vitamin D3 deficiency.