The multiyear Vitamin D and Type 2 Diabetes (D2d) study will enroll about 2,500 patients across 20 study sites. The study’s aim is to learn if 4,000 IU vitamin D will prevent or delay type 2 diabetes in adults >30 years old with prediabetes.
This dose is greater than the typical adult intake of 600–800 IU/day, but has been deemed appropriate for clinical research by the Institute of Medicine.
“Past observational studies have suggested that higher levels of vitamin D may be beneficial in preventing type 2 diabetes, but until this large, randomized and controlled clinical trial is complete, we won’t know if taking vitamin D supplements lowers the risk of diabetes,” said Anastassios G. Pittas, MD, the study’s principal investigator at Tufts Medical Center, Boston, MA.
Study researchers hypothesize that vitamin D can reduce the risk of diabetes risk by 25%. The double-blind study will also assess if sex, age or race affect the potential of vitamin D in reducing the risk of diabetes. Patients will be randomized to receive vitamin D or placebo.
Check-ups for the study will occur twice a year, and patients will receive regular health care through their own health care providers. The study will continue until enough people have developed type 2 diabetes to be able to make scientifically valid comparison between the two groups–likely to be about four years.
This study is funded by the National Institutes of Health.
For more information call (301) 496-4000 or visit D2dstudy.org.