This meta- analysis concludes that hypovitaminosis D is associated with increased risk of hyperglycemia both in diabetic and non-diabetic subjects .
There is evidence that vitamin D status is associated with type 2 diabetes .
Many observational studies have been performed investigating the relationship of vitamin D status and circulating biomarkers of glycemic regulation .
To find out whether this association holds , we conducted a systematic review and meta- analysis of cross sectional and longitudinal studies .
Vitamin D and incidence of diabetes: a prospective cohort study.
BACKGROUND & AIMS To investigate the relationship between levels of 25-hydroxyvitamin D and the  incidence of type 2 diabetes in a Spanish population . METHODS We undertook a population -based prospect i ve study in a population from southern Spain . The first phase of the study ( 1996 - 1998 ) included 1226 individuals . Of this original cohort , 988 persons were reassessed in 2002 - 2004 and 961 in 2005 - 2007 . Measurements were made of  25-hydroxyvitamin D and intact parathyroid hormone  in 2002 - 2004 and an  oral glucose tolerance test  was done in three time points . RESULTS The incidence of diabetes in subjects with 25-hydroxyvitamin D levels ≤ 18.5 ng/mL ( percentile 25 ) was 12.4 % vs 4.7 % in subjects with levels > 18.5 ng/mL. The likelihood of having diabetes during the four years of follow-up was significantly lower in the subjects with higher levels of 25-hydroxyvitamin D [ OR = 0.17 ( 0.05 - 0.61 ) ] . None of the subjects with levels higher than 30 ng/mL developed diabetes . CONCLUSION In this prospect i ve study , we found a significant inverse association between serum 25-hydroxyvitamin D levels and the risk for type 2 diabetes in a population from the south of Spain
This meta- analysis concludes that hypovitaminosis D is associated with increased risk of hyperglycemia both in diabetic and non-diabetic subjects .
There is evidence that vitamin D status is associated with type 2 diabetes .
Many observational studies have been performed investigating the relationship of vitamin D status and circulating biomarkers of glycemic regulation .
To find out whether this association holds , we conducted a systematic review and meta- analysis of cross sectional and longitudinal studies .