DASH lowers blood pressure in obese hypertensives beyond potassium, magnesium and fibre

The mechanism underlying blood pressure reduction in the high fruits and vegetables arm of the Dietary Approaches to Stop Hypertension (DASH) Study is unknown but may include potassium, magnesium and fiber. This study was designed to separate minerals and fiber from other components of DASH on blood pressure in abdominally obese metabolic syndrome subjects with prehypertension to Stage 1 hypertension (obese hypertensives). Fifteen obese hypertensives and 15 lean normotensives were studied on a standardized usual diet, randomized to DASH or usual diet supplemented with potassium, magnesium and fiber to match DASH, then crossed over to the complementary diet. All diets were three weeks long, isocaloric and matched for sodium and calcium. In obese hypertensives, blood pressure was lower after 3 weeks on DASH than usual diet (-7.6±1.4/-5.3±1.4 mmHg, p 0.50). DASH is more effective than potassium, magnesium, and fiber supplements for lowering blood pressure in obese hypertensives, which suggest that high fruits and vegetables DASH lowers blood pressure and improves endothelial function in this group by nutritional factors in addition to potassium, magnesium and fiber.