When people are told they have prediabetes, the focus is usually on preventing diabetes. But there is another, less discussed possibility: returning to normal glucose levels. This “regression to normal” matters—it is associated with a lower risk of future diabetes and its complications. The question is whether simple, safe interventions can help people get there.
To answer this, we looked across clinical trials of vitamin D in adults with prediabetes. Rather than focusing only on who developed diabetes, we asked a different question: who returned to normal? Across 10 trials and more than 4,000 participants, people who took vitamin D were more likely to regain normal glucose levels than those who did not.
The effect was modest but consistent. But these findings suggest that vitamin D may help shift the trajectory, not just slowing progression to diabetes, but moving glucose metabolism back toward normal.
