So far no study has investigated the effect of nitrates on endothelial function and bone microarchitecture in patients with diabetes. The investigators therefore propose to investigate the influence of nitrates on endothelial dysfunction and bone integrity in patients with type 2 diabetes. 40 patients with type 2 DM will be recruited into the study; 20 patients will receive 20 mg of oral isosorbide mononitrate daily and the other 20 will not receive the study drug. The investigators hope to demonstrate an improvement in endothelial function (by measuring skin blood flow) and bone integrity (by measuring markers of bone formation and bone resorption and bone mineral density - BMD) following 6 months of nitrate therapy.