More than two in five US adults have prediabetes, placing them at increased risk of developing Type 2 diabetes and its associated complications. New research suggests genetic testing could someday help identify which of these individuals are most likely to benefit from vitamin D supplementation, highlighting another potential role for laboratory medicine in disease prevention.
The study, published in JAMA Network Open, analyzed data from more than 2,000 adults enrolled in the D2d clinical trial, which evaluated whether daily vitamin D supplementation could reduce diabetes risk in people with prediabetes. Although the original trial found no significant benefit across the overall study population, researchers discovered that genetic differences may have influenced individual responses to treatment.
Specifically, participants with certain variations of the vitamin D receptor gene experienced a 19% lower risk of progressing to Type 2 diabetes when taking a daily high-dose vitamin D supplement.
For clinical laboratory professionals, the findings are notable because they point toward a future in which genetic testing may help guide more personalized prevention strategies for patients at high risk of diabetes.
Potential role for precision prevention
Researchers examined DNA samples from 2,098 participants and compared diabetes outcomes based on three common variations of the vitamin D receptor gene. The analysis found that some genetic subgroups appeared to benefit significantly from vitamin D supplementation, while others saw little to no effect.
The results may help explain why previous studies of vitamin D and diabetes prevention have produced mixed findings. Vitamin D receptors are present on insulin-producing pancreatic cells, suggesting the nutrient may play a role in insulin secretion and blood glucose regulation. Researchers believe genetic differences in those receptors could influence how effectively patients respond to supplementation.
“The findings may represent an important step toward developing a personalized approach to lowering the risk of developing type 2 diabetes among high-risk adults,” said Anastassios Pittas, MD, the study’s senior author, a professor of medicine at Tufts University School of Medicine, and chief of endocrinology, diabetes, and metabolism at Tufts Medical Center. “Part of what makes vitamin D appealing as a potential preventive tool is that it is inexpensive, widely available, and easy for people to take.”
The implications extend beyond vitamin D itself.
With more than 115 million Americans estimated to have prediabetes, laboratory testing remains a key tool for identifying at-risk patients before they develop Type 2 diabetes. Earlier detection can support preventive interventions that improve outcomes and potentially reduce healthcare costs associated with long-term complications.
Researchers cautioned that the findings do not support routine high-dose vitamin D supplementation and emphasized that additional studies are needed. The Dark Report recently published an article on a review of nearly 280,000 vitamin D test orders found that growing consumer interest in vitamin D and the rise of online ordering may be contributing to providers selecting the wrong assay. Researchers reported a sharp increase in orders for the specialized 1,25-dihydroxy vitamin D test, which is not intended to assess routine vitamin D status. The findings highlight how consumer health trends, electronic ordering systems, and payer policies can influence laboratory test utilization and costs.
This article was created with the assistance of Generative AI and has undergone editorial review before publishing.
