Evidence from trials with vitamin D and /or calcium supplementation suggests that combined vitamin D and calcium supplementation may have a role in the prevention of type 2 DM only in population s at high risk ( i.e. glucose intolerance ) .
Vitamin D and calcium insufficiency may negatively influence glycemia , whereas combined supplementation with both nutrients may be beneficial in optimizing glucose metabolism
CONTEXT Altered vitamin D and calcium homeostasis may play a role in the development of type 2 diabetes mellitus ( type 2 DM ) .
Circulating MMP9, vitamin D and variation in the TIMP-1 response with VDR genotype: mechanisms for inflammatory damage in chronic disorders?
BACKGROUND Vitamin-D deficiency and vitamin-D receptor genotype ( VDR ) are risk factors for several disorders with inflammatory components , including coronary heart disease ( CHD ) and diabetes , though the mechanisms involved are unclear . AIM To examine the hypothesis that vitamin D status modulates the matrix metalloproteinase ( MMP ) system in a population with a high prevalence of vitamin D deficiency , a situation affecting susceptibility to CHD and diabetes . DESIGN Prospect i ve cross-sectional , interventional and embedded studies . METHODS Circulating MMP2,9 , the inhibitor TIMP-1 and C-reactive protein ( CRP ) were measured during studies of vitamin-D deficiency as a risk factor for type 2 diabetes and CHD in 171 healthy British Bangladeshi adults , free of known diabetes or major illness .  Vitamin D status , VDR genotype , body-build , blood pressure , lipid and insulin profiles , glucose tolerance , fibrinogen , PAI-1 , folate and homocysteine were measured . Vitamin-D-deficient subjects were re-assessed after 1 years ' supplementation .  MMP , TIMP-1 and CRP levels were measured in 41 subjects halfway through 5-year follow-up . Independent determinants of circulating concentrations of MMP9 , TIMP-1 and CRP were assessed by multiple regression analysis . RESULTS Vitamin D status was the sole determinant of circulating MMP9 ( inversely ) and an independent determinant of CRP ( inversely ) . Determinants of TIMP-1 were MMP9 , systolic blood-pressure ( directly ) and VDR genotype ( TaqI ) . Significant reductions in MMP9 ( -68 % ) , TIMP-1 ( -38 % ) and CRP ( -23 % ) concentrations followed vitamin-D supplementation . DISCUSSION Vitamin-D insufficiency is associated with increased circulating MMP2,9 and CRP , correctable by supplementation . This finding provides a possible mechanism for tissue damage in chronic inflammatory conditions , including CHD and diabetes
Evidence from trials with vitamin D and /or calcium supplementation suggests that combined vitamin D and calcium supplementation may have a role in the prevention of type 2 DM only in population s at high risk ( i.e. glucose intolerance ) .
Vitamin D and calcium insufficiency may negatively influence glycemia , whereas combined supplementation with both nutrients may be beneficial in optimizing glucose metabolism
CONTEXT Altered vitamin D and calcium homeostasis may play a role in the development of type 2 diabetes mellitus ( type 2 DM ) .