ABSTRACT
A DASH (dietary approaches to stop hypertension) dietary pattern rich in fruits and vegetables and low-fat dairy products with increased dietary protein provided primarily from plant protein sources decreases blood pressure. No studies, however, have evaluated the effects of a DASH-like diet with increased dietary protein from lean beef on blood pressure and vascular health. The aim of this study was to study the effect of DASH-like diets that provided different amounts of protein from lean beef (DASH 28 g beef per day; beef in an optimal lean diet (BOLD) 113 g beef per day; beef in an optimal lean diet plus additional protein (BOLD+) 153 g beef per day) on blood pressure, endothelial function and vascular reactivity versus a healthy American diet (HAD). Using a randomized, crossover study design, 36 normotensive participants (systolic blood pressure (SBP), 116 ± 3.6 mm Hg) were fed four isocaloric diets,: HAD (33% total fat, 12% saturated fatty acids (SFA), 17% protein (PRO), 20 g beef per day), DASH (27% total fat, 6% SFA, 18% PRO, 28 g beef per day), BOLD (28% total fat, 6% SFA, 19% PRO, 113 g beef per day) and BOLD+ (28% total fat, 6% SFA, 27% PRO, 153 g beef per day), for 5 weeks. SBP decreased (P<0.05) in subjects on the BOLD+ diet (111.4 ± 1.9 mm Hg) versus HAD (115.7 ± 1.9). There were no significant effects of the DASH and BOLD diets on SBP. Augmentation index (AI) was significantly reduced in participants on the BOLD diet (-4.1%). There were no significant effects of the dietary treatments on diastolic blood pressure or endothelial function (as measured by peripheral arterial tonometry). A moderate protein DASH-like diet including lean beef decreased SBP in normotensive individuals. The inclusion of lean beef in a heart healthy diet also reduced peripheral vascular constriction.
