In meta-analyses of vitamin D and diabetes prevention trials, vitamin D lowers risk of developing diabetes in people at risk for type 2 diabetes (prediabetes). This study examined the effect of vitamin D on diabetes prevention, regression to normal glucose regulation (NGR) and individual glycemic measures in the D2d study among participants who were adherent to the study pills and did not take diabetes or weight loss medications or high-dose vitamin D outside of the study,
We found that vitamin D reduced risk of developing diabetes by 16%. At the last study visit, we found that participants on vitamin D were 31% to 45% (depending the definition) more likely to have regressed to normal glucose regulation from prediabetes. During follow-up, glycemic measures increased in both groups, as expected. The mean difference in fasting blood glucose favored vitamin D.
We concluded that among participants adherent to the trial protocol, vitamin D lowered the risk of developing diabetes and increased the likelihood of NGR at the end of the study. These results highlight the importance of adherence to the vitamin D intervention.
The manuscript is published in Diabetes Research and Clinical Practice.
