Vitamin D Supplementation, Glycemic Control, and Insulin Resistance in Prediabetics

A Meta-Analysis

Naghmeh Mirhosseini; Hassanali Vatanparast; Mohsen Mazidi; Samantha M. Kimball


J Endo Soc. 2018;2(7):687-709. 

In This Article


Vitamin D deficiency and type 2 diabetes are escalating health problems worldwide. The results presented here provide promising evidence that vitamin D supplementation improves glycemic control and attenuates insulin resistance in prediabetics or individuals at high risk of developing diabetes. The amount of vitamin D most likely to produce a response is ≥88 μg/d (3500 IU/d), a level that is close to the current upper level of intake recommended by Health Canada, the US Institute of Medicine, and the European Food Safety Authority. Even though the effect size for vitamin D is not comparable to the effect of metformin or other glycemic control medications, over a long period of time and when administered at the population level, vitamin D supplementation may offer an affordable, safe, and accessible preventive measure.