THE EFFECT OF PLANT-BASED DIETS ON BLOOD PRESSURE: A SYSTEMATIC REVIEW AND META-ANALYSIS OF CONTROLLED CLINICAL TRIALS. (April 2021)

• Record Type: Journal Article
• Authors: Gibbs, Joshua; Gaskin, Eleanor; Ji, Chen; Miller, Michelle; Cappuccio, Francesco
• Is Part Of: Journal of hypertension. Volume 39(2021)e-Supplement 1
• Publication Date: 2021-04
• Subjects: Hypertension -- Periodicals; Hypertension -- Periodicals; 616.132005
• DOI: 10.1097/01.hjh.0000748212.53272.08
• Languages: English
• ISSNs: 1473-5598

Abstract

Abstract : Objective: Strict vegetarian diets with no animal products are associated with low blood pressure (BP). It is not clear whether less strict plant-based diets (PBD) exert similar effects. We assessed whether less strict PBDs reduce BP in controlled clinical trials. Design and method: We carried out a systematic review and a meta-analysis of all published intervention trials assessing the effects of PBDs on BP according to PRISMA guidelines (PROSPERO: CRD42019153716). On 14 June 2019 we performed a systematic search of publications using MEDLINE (1966–2019), EMBASE (from 1980), CINHAL, WoS and manual searches without language restrictions. Inclusion criteria were age > 18 years, PBD as an intervention, defined as dietary patterns that support high consumption of fruits, vegetables, whole grains, legumes, nuts and seeds, and avoid the consumption of most or all animal products, mean differences in systolic/diastolic BP between PBD and control diet, controlled clinical trial. Standardised mean differences in BP and 95% C.I. were pooled using a random effect model. Quality, sensitivity, heterogeneity and publication bias were assessed. Results: Thirty-nine studies met the inclusion criteria. They included 8, 203 participants (4, 333 in intervention; 3, 870 control groups). Median sample size was n = 65 (range 11–4, 717) and mean age of the participants 50.5 yrs (range 25.6–71.0). All were controlled trials (duration 1.4 to 208 wks, median 12 wks). Of the 39 trials, 36 were randomised. Seven were crossover. Two were single-blinded. The interventions were DASH diet (n = 11), Mediterranean diet (MD, n = 8), vegan diet (VD, n = 8), lacto-ovo vegetarian diet (LOVD, n = 5), healthy Nordic diet (ND, n = 3), high fiber diet (HFD, n = 3), and high fruit and vegetables diet (FVD, n = 2). In the pooled analysis, PBDs were associated with lower systolic BP (DASH 5.53 mmHg [-7.95, -3.12], MD -0.95 mmHg [-1.70, -0.20], VD -1.61 mmHg [-4.53, 1.31], LOVD -5.47 mmHg [-7.60, -3.34], ND -4.47 mmHg [-7.14, -1.81], HFD -0.65 mmHg [-1.83, 053], FVD -0.57 mmHg [-7.45, 6.32]. Similar effects were seen on diastolic BP. There was no evidence of publication bias and some heterogeneity was detected. Conclusions: PBDs with limited or no animal products lower both systolic and diastolic BP, across sex, age and body mass index.