Ginger Supplementation and Blood Pressure in Adults: A GRADE-Based Systematic Review and Dose-Response Meta-Analysis...

Ginger (Zingiber officinale L.) contains bioactive compounds with vasodilatory properties that may benefit blood pressure (BP) regulation. However, findings from studies remain inconsistent. This systematic review and meta-analysis aimed to evaluate the effect of ginger supplementation on BP in adults.

The literature was systematically searched in PubMed, Web of Science, and Scopus from database inception through May 1, 2026, to identify eligible randomized controlled trials (RCTs) evaluating systolic and diastolic blood pressure (SBP, DBP). Pooled effect estimates were calculated as weighted mean differences (WMDs) using a random-effects model. Subgroup and sensitivity analyses, publication bias assessments, and both linear and nonlinear dose-response analyses were conducted. The risk of bias was evaluated using the RoB 2 tool, and the certainty of the evidence was assessed according to the GRADE framework.

Twelve unique RCTs contributed 13 effect sizes for SBP and 12 effect sizes for DBP. Ginger supplementation significantly reduced SBP (WMD: -5.03 mmHg, 95% CI: -8.49, -1.57; p = 0.004) and DBP (WMD: -2.03 mmHg, 95% CI: -3.90, -0.15; p = 0.034). Subgroup-specific reductions were observed in trials enrolling participants with elevated baseline BP, using doses ≥ 2000 mg/day, including both sexes, and enrolling participants with obesity. Nonlinear dose-response analyses confirmed a significant inverse association between ginger dose and BP, whereas intervention duration had no meaningful influence. Findings remained robust in sensitivity analyses, and no evidence of publication bias was detected. GRADE assessment rated the certainty of the evidence as low, downgraded only for inconsistency.

Ginger supplementation was associated with modest reductions in BP, with potentially greater effects in higher-risk populations and at doses ≥ 2000 mg/day. However, substantial heterogeneity, short trial durations, and limited robustness of the DBP findings reduce confidence in these estimates. Further high-quality, long-term RCTs are needed before definitive clinical or dosing recommendations can be made.