The Differential Role of Vitamin D in Type 2 Diabetes Management and Control in Minority Populations.

Vitamin D deficiency is associated with incidence of type 2 diabetes (T2DM) as well as poor glycemic control among T2DM patients, yet comparative studies of its association among ethnic minority populations are scarce. Using baseline data from a behavioral intervention study of Korean Americans (KAs) with T2DM (N = 250 KAs) and the NHANES data set, we explored differential roles of vitamin D on HbA1C level or T2DM control in several racial groups. Significantly more KAs (55.2%) were vitamin D-deficient (U.S. average, 37.8%). Both common and unique correlates of vitamin D deficiency in minority populations were identified, including significant associations between Vitamin D and HbA1C in both non-diabetic and diabetic populations. Future studies are warranted to explain the causal mechanism of the effect of vitamin D and glycemic control as well as to examine contextual factors associated with vitamin D deficiency in certain minority groups.Clinical Trials Registry: Identifier NCT01264796.