It is quite evident that high blood pressure is more common amongst Blacks than Whites and persons with darker skin generally produce less vitamin D, primarily at higher latitudes where UV radiation is less intense and the climate is cooler, leading to less skin exposure.
The study has been conducted by Dr. Kevin Fiscella from the University of Rochester School of Medicine, US and his colleagues.
The research suggests that low vitamin D level may contribute to elevated blood pressure, which explains why thousands of Blacks die annually from heart disease and stroke.
The researchers compared the average systolic blood pressure and blood levels of Vitamin D of Blacks and Whites taking data from the National Health and Nutrition
Examination Survey 2001-2006 for 1,984 of the former and 5,156 of the later aged 20 years and above. They found that overall, Blacks had significantly lower levels of vitamin D in their blood than Whites and blood levels of vitamin D were linked to systolic blood pressure.
"Our study adds to the growing body of evidence showing that low levels of vitamin D among Blacks contribute to cardiovascular disparities. We also know that blood pressure is highest among Blacks living in the US, where UV exposure is low.
Taken together, these findings point towards vitamin D deficiency as a potential contributor to higher rates of vascular dysfunction, here hypertension among Blacks living in the US. Further, work is required to determine whether vitamin D supplementation could reduce these racial disparities."
The study has been published in the Journal of General Internal Medicine.