The Antihypertensive Effects of Hibiscus sabdariffa L. Tea: A Systematic Review of Clinical Trials

Abstract

Introduction: Hypertension is a major risk factor for cardiovascular disease. Hibiscus sabdariffa L. (roselle) tea is a popular traditional remedy for high blood pressure. This review systematically evaluates its efficacy in lowering blood pressure in pre-hypertensive and hypertensive adults.

Methods: A systematic search of several electronic databases was performed for RCTs comparing hibiscus tea to placebo or other antihypertensives. The primary outcomes were changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP).

Results: Ten RCTs met the inclusion criteria. The meta-analysis revealed that daily consumption of hibiscus tea resulted in a significant mean reduction in both SBP and DBP compared to placebo. The magnitude of the effect was comparable to some standard antihypertensive medications in mild hypertension.

Discussion: The antihypertensive effect of hibiscus is likely due to its diuretic and angiotensin-converting enzyme (ACE) inhibiting properties, attributed to its high content of anthocyanins and polyphenols. It is generally well-tolerated.

Conclusion: Hibiscus sabdariffa tea is an effective, evidence-based dietary intervention for lowering blood pressure in individuals with mild to moderate hypertension.