For long scientists have debated about the possible reasons for the difference in the blood pressure levels between the whites and the blacks and now a new study has shed some light in this regard. A study which was conducted by the University of Rochester School of Medicine has labeled Vitamin D as a likely factor.
The study conducted by Dr. Kevin Fiscella and colleagues from the University of Rochester School of Medicine in the US, reveals that a lower level of vitamin D is responsible for the difference in blood pressure levels. And this has something to do with the color of the skin. Apparently the darker the skin the lower is the Vitamin D level and so higher is the blood pressure.
Normally, blacks tend to have high blood pressure when compared to the whites as the dark skin produces less vitamin D. This disparity can be attributed to the climatic conditions as well. This is especially true with regard to the blacks living in higher latitudes where they are less exposed to the sun's UV radiations and the climate is also cold, and hence, the skin is less exposed to the sun. The data suggests that, at the population level, more blacks have been reported to have died annually due to heart diseases and stroke when compared to whites because of the seemingly modest Black-White differences in blood pressure.
The researchers observed the information obtained from the National Health and Nutrition Examination Survey 2001 – 2006 for 1,984 blacks and 5,156 white participants who are either 20 or over. The scientists carried a detailed comparison of the average systolic blood pressure and blood levels of Vitamin D between the black and white participants respectively. The findings revealed that the blacks had lower levels of Vitamin D when compared to the whites and the vitamin D levels were linked to systolic blood pressure. This difference in vitamin D levels between the two races accounted for a quarter of the blood pressure levels between the two. And when the participants on blood pressure medication were removed from the list, the vitamin D impact was accounted for 40 percent for the disparity in the 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," says Kevin, the lead researcher.
