Improvement of hypertension, endothelial function and systemic inflammation following short-term supplementation with red beet (Beta vulgaris L.) juice: a randomized crossover pilot study

Abstract

Hypertension is a major risk factor for cardiovascular disease and has a prevalence of about one billion people worldwide. It has been shown that adherence to a diet rich in fruits and vegetables helps in decreasing blood pressure (BP). This study aimed to investigate the effect of raw beet juice (RBJ) and cooked beet (CB) on BP of hypertensive subjects. In this randomized crossover study, 24 hypertensive subjects aged 25-68 years old were divided into two groups. One group took RBJ for 2 weeks and the other group took CB. After 2 weeks of treatment, both groups had a washout for 2 weeks then switched to the alternate treatment. Each participant consumed 250 ml day(-1) of RBJ or 250 g day(-1) of CB each for a period of 2 weeks. Body weight, BP, flow-mediated dilation (FMD), lipid profile and inflammatory parameters were measured at baseline and after each period. According to the results, high-sensitivity C-reactive protein (hs-CRP) and tumour necrosis factor alpha (TNF-alpha) were significantly lower and FMD was significantly higher after treatment with RBJ compared with CB (P<0.05). FMD was significantly (P<0.05) increased, but systolic and diastolic BP, intracellular adhesion molecule-1 (ICAM-1), vascular endothelial adhesion molecule-1 (VCAM-1), hs-CRP, interleukin-6, E-selectin and TNF-alpha were significantly (P<0.05) decreased with RBJ or CB. Total antioxidant capacity was increased and non-high-density lipoprotein (HDL), low-density lipoprotein (LDL) and total cholesterol (TC) were decreased with RBJ but not with CB. Although both forms of beetroot were effective in improving BP, endothelial function and systemic inflammation, the raw beetroot juice had greater antihypertensive effects. Also more improvement was observed in endothelial function and systemic inflammation with RBJ compared with CB.