The goal of the Vitamin D and type 2 diabetes (D2d) study is to determine whether vitamin D supplementation is safe and effective in delaying the onset of type 2 diabetes in people at risk for the disease and to gain a better understanding of how vitamin D affects glucose metabolism.
There are over 79 million Americans who are at increased risk for developing type 2 diabetes. Lifestyle changes, such as healthy eating, exercise and weight loss, can decrease the chances of developing diabetes. However, many people still develop diabetes despite efforts at changing their lifestyle. Therefore, there is a continued need for the identification of modifiable risk factors and interventions that are safe, inexpensive and easy to implement to prevent type 2 diabetes and decrease disease burden. Based on recently published studies, vitamin D has emerged as a potential determinant of type 2 diabetes risk. However, according to reports by the Institute of Medicine and the Endocrine Society, the evidence to support vitamin D supplementation for prevention of diabetes is inconclusive and there is a need for definite studies in this area, such as the D2d study.
The D2d study is a large multi-center clinical trial conducted in twenty cities around the United States. The D2d study will enroll approximately 2,400 participants who are at risk of developing type 2 diabetes. Participants are randomly assigned to receive either vitamin D or placebo and be followed for up to 4 years for development of diabetes. The D2d study is expected to define the role of vitamin D supplementation in modifying diabetes risk in people at risk for the disease.