Dose-dependent effect of vinegar on blood pressure: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials

Abstract

Background: There are controversial findings regarding the effect of vinegar on blood pressure based on the evidence accumulated so far. Methods: A systematic search was conducted through PubMed, Scopus, and ISI Web of Science up to April 2022. We estimated the change in blood pressure for each 30 ml/d increments in vinegar consumption in each trial and then, calculated the mean difference (MD) and 95 %CI using a fixed-effects model. A dose-response meta-analysis of differences in means provided us with the estimation of the dose-dependent effect. The certainty of evidence was rated by the GRADE tool. Results: Each 30 ml/d increment in vinegar consumption reduced SBP by − 3.25 mmHg (95 %CI: − 5.54, − 0.96; I2 = 67.5 %, GRADE = low). Levels of SBP decreased linearly and slightly (Pnonlinearity = 0.69, Pdose-response = 0.02) up to vinegar consumption of 30 ml/d (MD30 ml/d: − 3.36, 95 %CI: − 5.77, − 0.94). Each 30 ml/d increment in vinegar consumption reduced DBP by − 3.33 mmHg (95 %CI: − 4.16, − 2.49; I2 = 57.1 %, GRADE = low). Levels of DBP decreased linearly and slightly (Pnonlinearity = 0.47, Pdose-response = 0.004) up to vinegar consumption of 30 ml/d (MD30 ml/d: − 2.61, 95 %CI: − 4.15, − 1.06) Conclusions: According to the findings, vinegar significantly reduces systolic and diastolic blood pressure and may be considered an adjunct to hypertension treatment. Thus, clinicians could incorporate vinegar consumption as part of their dietary advice for patients.

Keywords

• Vinegar
• Acetic acid
• Blood pressure
• Hypertension
• Systematic review
• Dose-response meta-analysis