Does hibiscus tea lower blood pressure?

Reviews of trials find hibiscus tea lowers systolic and diastolic pressure by a few points, most clearly in people with raised pressure.

Published October 2026

Short answer

Yes: hibiscus tea modestly lowers blood pressure, about 5-8 mmHg systolic on average, but it is no substitute for prescribed treatment. Evidence grade B (Moderate). Meta-analyses of randomised trials, newest covering 26 trials with about 1,800 people; downgraded once because blood pressure is a surrogate marker.

Key takeaways

Pooled trials find hibiscus lowers systolic pressure by about 5-8 mmHg and diastolic by about 3-4 mmHg [1][2].
The newest review of 26 trials (1,797 people) found dose-dependent drops that looked similar on average to blood-pressure drugs [3].
People starting with higher pressure saw bigger falls [1][4].
It is generally well tolerated, but longer-term safety data are limited, so anyone on blood-pressure medicines should check with a doctor first [3].

The short version

Hibiscus Tea, brewed from Hibiscus sabdariffa calyces and also called sour tea or roselle, modestly lowers blood pressure in trials [5][1]. Pooled results show systolic pressure falling by about 5-8 mmHg and diastolic by about 3-4 mmHg [1][2]. The effect is most useful as part of diet changes for raised pressure, not as a replacement for prescribed medicines [4][6].

What the studies show

A 2015 meta-analysis of 5 trials (390 people) found hibiscus lowered systolic pressure by 7.58 mmHg and diastolic by 3.53 mmHg, with bigger drops in people starting from higher pressure [1]. A 2020 meta-analysis of 7 trials (362 people) found falls of 4.71 mmHg systolic and 4.08 mmHg diastolic, plus lower fasting blood sugar of 3.67 mg/dL [2]. The newest evidence, a 2025 umbrella review of 26 trials with 1,797 people, found dose-dependent blood-pressure reductions against placebo and other teas, roughly similar on average to blood-pressure drugs, with credible drops of over 10 mmHg in people over 50, in trials longer than four weeks, and in low-bias trials [3]. In the best-known single trial, 65 pre- and mildly hypertensive adults drinking three cups a day for 6 weeks lowered systolic pressure by 7.2 mmHg against 1.3 mmHg with placebo, while the diastolic change did not differ from placebo [4]. Against standard drugs, an 8-week trial of a hibiscus-olive product matched captopril with drops of about 15/10 mmHg in every group [7]. A 4-week trial found ramipril lowered systolic pressure more than hibiscus powder (16.7 against 11.2 mmHg), with similar diastolic falls [6]. A 4-week Nigerian trial in mild-to-moderate hypertension found hibiscus lowered pressure at least as well as hydrochlorothiazide without upsetting electrolytes [8].

The nuances

A strict 2021 Cochrane review judged the evidence insufficient, because only one small trial of roselle capsules against placebo in 52 people with diabetes met its narrow criteria, with very uncertain estimates [5]. Most positive trials were short (4-8 weeks) and small, and some tested hibiscus mixed with olive leaf or lemon verbena, which blurs the hibiscus-only effect [7][9]. Single-dose studies show little: one hibiscus drink did not change blood pressure over two hours [10]. Safety looks reassuring so far, with no higher risk of adverse events in the 2025 review, though its authors say longer-term and higher-dose safety still needs monitoring [3]. No pregnancy or breastfeeding safety data appeared in the reviews read, so caution is warranted there [3][11].

What this means for you

The amount most often tested is 2-3 cups of brewed hibiscus tea a day for several weeks [4][12]. People with normal pressure see little change, while people with raised pressure see the clearest benefit [4][1]. Because it genuinely lowers pressure, combining it with blood-pressure medicines could push pressure too low, so talk to a doctor first if you take them [3][6].

Go deeper

Hibiscus Tea — Hibiscus tea modestly lowers blood pressure, roughly 5-8 mmHg systolic and 3-4 mmHg diastolic across pooled trials, with bigger drops in people starting higher.