The effect of propolis supplementation on blood pressure: a systematic review and meta-analysis of controlled trials.

Introduction: The current meta-analysis aimed to determine the efficacy of propolis supplementation on hypertension.

Evidence acquisition: The systematic review and meta-analysis. were undertaken on five online databases to find clinical trials assessing the effects of propolis on systolic blood pressure (SBP) and diastolic blood pressure (DBP) markers up to October 2023. The pooled estimation of the weighted mean difference (WMD) and the corresponding 95% confidence intervals (CI) were calculated using a fixed-effect model. Egger's regression test was used to assess publication bias.

Evidence synthesis: A significant decrease was observed in SBP levels following propolis supplementation (WMD=-5.58 mmHg, 95% CI: -7.74, -3.42; I²=42.99%, P=0.08). However, no significant change was found in the levels of DBP (WMD=-1.34 mmHg, 95% CI: -6.10, 3.41; I²=75.94%, P<0.01). Moreover, studies with an experimental design (-5.53, 95% CI: -13.24, 2.18) and trials with <30 individuals (-3.96, 95% CI: -7.98, 0.06) did not demonstrate a significant impact of propolis on SBP levels. In trials with an experimental design, a substantial decrease in DBP levels was seen in subgroup analyses after propolis supplementation (-9.29, 95% CI: -12.50, -6.08).

Conclusions: The results of the study revealed the positive effects of propolis supplementation in the context of hypertension, as evidenced by a reduction in SBP levels.