Increasing daily intake of vitamin D3 can significantly reduced blood pressure in blacks, according to a new study published in the journal Hypertension. The study found a 3-month regimen of daily vitamin D supplementation increased circulating blood levels of vitamin D and resulted in a decrease in systolic blood pressure ranging from .7 to 4 mmHg, compared with no change in participants who received a placebo.
“Although this needs to be studied further, the greater prevalence of vitamin D deficiency among African-Americans may explain in part some of the racial disparity in blood pressure," said John P. Forman, M.D., M.Sc., lead author of the study and assistant professor of medicine in the Renal Division and Kidney Clinical Research Institute at Brigham and Women’s Hospital in Boston.
Black Americans have higher rates of hypertension and lower levels of circulating 25-hydroxyvitamin D (vitamin D3 or cholecalciferol) than the rest of the U.S. population. Few studies have included enough blacks to determine whether vitamin D supplements might reduce the racial disparity.
Researchers from seven major teaching hospitals conducted a four-arm, randomized, double-blinded study of 250 black adults. They tested blood pressure after a 3-month regimen of daily vitamin D supplementation at one of three doses, and compared the findings with a group taking placebo vitamins: taking 1,000 units of vitamin D each day for three months was associated with a .7 mm Hg decrease in systolic blood pressure; taking 2,000 units was linked to a 3.4 mm Hg decrease; taking 4,000 units netted a 4 mm Hg drop; and participants taking placebo supplements had an average increase of 1.7 mm Hg.
Forman said the gains they saw were significant but modest. Furthermore, diastolic blood pressure didn’t change in any of the four groups.
Vitamin D deficiency has been linked to a number of health issues, including obesity, cancer, brain health. For more information about recent research on vitamin D, download “Vitamin D—Illuminating the Sunshine Vitamin" slideshow and the free digital issue "2012: A Year in Review" on Food Product Design.
