Vitamin D supplementation may slow diabetes progression

Vitamin D supplementation may slow the progression of type 2 diabetes in newly diagnosed patients and those with prediabetes, according to a new study published in the European Journal of Endocrinology.

In the study, researchers from Université Laval in Quebec examined the effect of vitamin D supplementation on glucose metabolism in patients newly diagnosed with type 2 diabetes or identified as at high risk of developing the condition. Markers of insulin function and glucose metabolism were measured before and after six months of high-dose vitamin D supplementation, approximately five to 10 times the recommended dose.

Although only 46 percent of study participants were determined to have low vitamin D levels at the start of the study, supplementation with vitamin D significantly improved the action of insulin in muscle tissue of participants after six months, according to Claudia Gagnon, PhD, corresponding author and lead researcher.

The reason we saw improvements in glucose metabolism following vitamin D supplementation in those at high risk of diabetes, or with newly diagnosed diabetes, while other studies failed to demonstrate an effect in people with long-standing type 2 diabetes is unclear,” Gagnon said. “This could be due to the fact that improvements in metabolic function are harder to detect in those with longer-term disease or that a longer treatment time is needed to see the benefits."

Researchers say the findings suggest that high-dose supplementation of vitamin D can improve glucose metabolism to help prevent the development and progression of diabetes. Gagnon suggests future studies should evaluate whether there are individual clinical or genetic factors that affect how different people respond to vitamin D supplementation and if the positive effect on metabolism is maintained in the longer term.

“Type 2 diabetes and prediabetes are a growing public health concern and although our results are promising, further studies are required to confirm our findings, to identify whether some people may benefit more from this intervention, and to evaluate the safety of high-dose vitamin D supplementation in the long term,” Gagnon said. “Until then, I would suggest that current vitamin D supplementation recommendations be followed."