Impact of pomegranate juice on blood pressure: A systematic review and meta-analysis

Despite the importance of polyphenol-rich fruits in decreasing cardiovascular mortality, the impact of pomegranate juice (PJ) on blood pressure is still unclear. To determine the effect of PJ on blood pressure. PubMed, Scopus, ISI Web of Science, and Cochrane Library were searched comprehensively using relevant keywords. All studies using pomegranate juice alone were included although limited to human studies and the English language. A random-effects model and the generic inverse variance approach were used to determine quantitative data synthesis. Meta-analysis of 14 clinical trials (n = 573 individuals) demonstrated a reduction in systolic BP (SBP) with pomegranate juice (MD: -5.02 mmHg, 95% CI: -7.55 to -2.48, p < 0.001). Effect of study duration showed pomegranate juice intake ≤2 months significantly decreased SBP (MD: -4.59 mmHg, 95% CI: -7.10 to -2.08, p < 0.001) and DBP (MD: -2.94 mmHg, 95% CI: -5.25 to -0.63, p = 0.01). Consumption of ≤300 mL pomegranate juice daily reduced SBP (MD: -6.11 mmHg, 95% CI: -9.22 to -3.00, p < 0.001). Counterintuitively, >300 mL/day of pomegranate juice showed no effect on SBP (MD: -3.28 mmHg, 95% CI: -6.85 to 0.27, p = 0.07) but a significant DBP reduction occurred (MD: -3.10 mmHg, 95% CI: -5.74 to -0.47, p = 0.02). Meta-regression showed that the SBP-lowering effect of pomegranate juice was associated with the dose of supplementation (p < 0.001). Pomegranate juice appeared to decrease SBP and DBP in a dose-dependent manner, but the benefit was lost after 2 months of pomegranate juice intake.