Effects of beetroot juice on blood pressure in hypertension according to European Society of Hypertension Guidelines: A systematic review and meta-analysis

Aims: It has been suggested that nitrate-rich beetroot juice (BRJ) reduces blood pressure (BP) in various populations. We aimed to investigate the effect of BRJ on BP in adults with hypertension according to the European Society of Hypertension Guidelines (clinical BP >= 140/>= 90 mmHg) and whether BRJ can be considered as an adjunct to hypertension drug treatment, by conducting a meta-analysis of randomized controlled trials. Data synthesis: PubMed, SCOPUS, Medline Ovid, Cinahl, Cochrane Library and Web of Science were searched from inception until April 13, 2024 to identify randomized controlled trials of BRJ versus placebo, water, or no intake. Risk of bias was assessed using a standardized appraisal instrument from the Swedish Agency for Health Technology and Assessment of Social Services, which is based on the Cochrane risk-of-bias tool for randomized trials. The pooled BP effect size was calculated using random effects models and meta-regression. Certainty of evidence was assessed using GRADE. Eleven trials (349 patients) were included. BRJ yielded a significant reduction in clinical systolic BP compared with placebo mean difference (MD) -5.31 mmHg (95% CI -7.46, -3.16; I-2 = 64%, GRADE circle plus circle plus OO). There was no significant effect on clinical diastolic BP or 24-h BP outcomes, and the heterogeneity was moderate to high. Conclusions: Daily ingestion of 200-800 mg of nitrate from BRJ may reduce clinical systolic BP in hypertensive individuals with no sign of development of tolerance. Certainty of evidence is low, and results should be interpreted with caution. (c) 2024 The Author(s). Published by Elsevier B.V. on behalf of The Italian Diabetes Society, Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and Department of Clinical Medicine and Surgery, Federico II University. This is an open access under the CC BY license (http://creativecommons.org/licenses/by/4.0/).