Vitamin D and Arterial Hypertension: Facts and Myths

Purpose of review: Vitamin D and its derivatives are biologically active fat-soluble steroid hormones, which are transcription factors for numerous genes. The results of several observational studies suggest the relationship between plasma concentration of vitamin D and the risk of arterial hypertension, as well as between the intensity of insolation and the risk of arterial hypertension.

Recent findings: Based on the results of the abovementioned studies, it was hypothesized that vitamin D is characterized by the antihypertensive properties. Animal experiments have shown that vitamin D reduces activity of the renin-angiotensin-aldosterone system and improves vasorelaxation of blood vessels. Results of clinical studies did not confirm these results. Moreover in interventional clinical trials, it was documented that supplementation of vitamin D did not reduce blood pressure. The influence of exposure to sunshine at different wave lengths on blood pressure was examined in clinical studies and it was found that ultraviolet A radiation (UVA) lead to the release of nitric oxide from the skin. This might explain lower level of blood pressure in subjects from the regions with a higher rate of insolation. The aim of this review is to summarize current knowledge concerning the relationship between vitamin D and arterial hypertension based on both observational and interventional studies.

Keywords: Hypertension; Obesity; Solar radiation; Vitamin D.