Vitamin D supplements significantly reduced blood pressure in the first large controlled study of African-Americans

In the prospective trial, a three-month regimen of daily vitamin D increased circulating blood levels of vitamin D and resulted in a decrease in systolic blood pressure ranging from .7 to four mmHg (depending upon the dose given), compared with no change in participants who received a placebo. Systolic blood pressure, the top and highest number in a reading, is pressure in the arteries when the heart beats. Diastolic blood pressure, the bottom and lower number, is pressure in the arteries between heart beats. "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, Massachusetts. African-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.