Controversy in the link between vitamin D supplementation and hypertension.

Vitamin D affects a range of pathophysiological processes pertinent to the control of blood pressure, including endothelial function, inflammation and renin-angiotensin system activity. Observational data show a clear relationship between 25-hydroxyvitamin D levels and both current blood pressure and incident hypertension. However, recent trial data have shown no significant effect of vitamin D supplementation on blood pressure, even at high doses, low vitamin D levels and in patients with high baseline blood pressure. Vitamin D might still benefit cardiovascular health through mechanisms other than blood pressure reduction, but data from large trials are required to show this. In the meantime, vitamin D has no place in controlling blood pressure either at the individual or the population level.