This result [that supplementing with large infusions of Vitamin D3] was duplicated in a second placebo-controlled study of 61 participants given placebo, 100,000 IU or 200,000 IU of Vitamin D3.
Though the Vitamin D made a very small difference in their blood pressure (which was still too high after supplementation) the study found
here was no significant difference in the primary outcome of endothelial function at 8 weeks (placebo 5.2%, n=22; 100,000 IU 4.3%, n=19; 200,000 IU 4.9%, n=17) or at 16 weeks. Insulin resistance and glycosylated haemoglobin did not improve with either dose of vitamin D3.The effect of different doses of vitamin D3 on markers of vascular health in patients with type 2 diabetes: a randomised controlled trial.M. D. Witham et al. Diabetologia Volume 53, Number 10, 2112-2119, DOI: 10.1007/s00125-010-1838-1