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 .
Serum 25(OH)D and Type 2 Diabetes Association in a General Population
OBJECTIVE This study aim ed to examine vitamin D status as a determinant for development of type 2 diabetes and deterioration of glucose homeostasis . RESEARCH DESIGN AND METHODS A r and om sample of the general population of Copenhagen , Denmark , was taken as part of the Inter99 study . Included were 6,405 men and women aged 30–65 years at baseline ( 1999–2001 ) , with 4,296 participating in the follow-up examination 5 years later ( 2004–2006 ) .  Vitamin D was determined at baseline as serum 25-hydroxyvitamin D [ 25(OH)D ] . Diabetes was defined based on an oral glucose tolerance test and a glycosylated hemoglobin ( HbA1c ) test . Secondary outcomes included continuous markers of glucose homeostasis . RESULTS The risk of incident diabetes associated with a 10 nmol/L increase in 25(OH)D was odds ratio ( OR ) 0.91 ( 95 % CI 0.84–0.97 ) in crude analyses . The association became statistically nonsignificant after adjustment for confounders , with an OR per 10 nmol/L of 0.94 ( 0.86–1.03 ) . Low 25(OH)D status was significantly associated with unfavorable longitudinal changes in continuous markers of glucose homeostasis after adjustment for confounders . Fasting and 2-h glucose and insulin as well as the degree of insulin resistance increased significantly more during follow-up among those with low 25(OH)D levels compared with those with higher levels . CONCLUSIONS Low 25(OH)D status was not significantly associated with incident diabetes after adjustment for confounders . However , it was significantly associated with unfavorable longitudinal changes in continuous markers of glucose homeostasis , indicating that low vitamin D status could be related to deterioration of glucose homeostasis
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 .