Diabetes/metabolism research and reviews 2017 11 24() doi 10.1002/dmrr.2969
Several studies have suggested the role of vitamin D in glycemic metabolism and its potential as adjuvant treatment of type 2 diabetes mellitus. Thus, this review discusses the role of vitamin D in the glycemic control of individuals with type 2 diabetes mellitus and evaluates the effect of vitamin D supplementation on glycemic markers in this population.
Literature searches were performed in the BIREME, LILACS, and PubMed databases using the Medical Subject Headings and words related to vitamin D, type 2 diabetes mellitus, and glycemic control. Interventional and observational studies were considered eligible. The evaluation of the included studies was independently performed by two evaluators at all stages of selection, data extraction, and bias risk assessment. The primary outcome was the relationship between vitamin D levels and glucose metabolism markers in T2DM individuals. The secondary outcome was the effect of vitamin D supplementation in the glycemic control markers in T2DM individuals.
The inverse relationship between vitamin D and variables of glucose metabolism was verified. Interventional studies revealed that vitamin D supplementation did not alter glycemic control markers in most studies. Few studies have shown positive effects with a significant reduction in the percentage of glycated hemoglobin, insulin and glucose concentrations, and changes in homeostatic model assessment-insulin resistance and beta cell, and quantitative insulin sensitivity check index.
Therefore, despite the association of vitamin D with glucose metabolism, there is insufficient evidence of the beneficial effects of its supplementation on the metabolic control of type 2 diabetes mellitus.