Low vitamin D levels have a causal role in the development of high blood pressure (hypertension), say researchers.
The findings suggest that vitamin D supplementation could be effective in combating some cases of hypertension.
Study leader Professor Elina Hypponen from the University of South Australia, said in view of the costs and side effects associated with antihypertensive drugs, the potential to prevent or reduce blood pressure and therefore the risk of hypertension with vitamin D is very attractive.
The Mendelian randomisation study used genetic data from the D-CarDia collaboration, involving over 146 500 individuals of European ancestry from across Europe and North America.
Researchers used two common genetic variants that affect circulating 25-hydroxyvitamin D or 25(OH)D concentrations (which are generally used to determine a person's vitamin D status), to measure the causal effect between vitamin D status and blood pressure and hypertension risk.
They found that for each 10 per cent increase in 25(OH)D concentration there was a drop in diastolic blood pressure (-0.29 mm Hg) and systolic blood pressure (-0.37 mm Hg), and an 8.1 per cent decrease in the odds of developing hypertension.
According to Professor Hypponen, "Mendelian randomisation helps to determine cause and effect because by using genetic data we can better avoid confounding, reverse causation, and bias.
However, because we cannot exclude the possibility that our findings were caused by chance, they need to be replicated in an independent, similarly powered study. Further studies using randomised controlled trials are also needed to confirm causality and the potential clinical benefits of vitamin D supplementation."
The findings have been published in The Lancet Diabetes and Endocrinology.