From the Guidelines
Hibiscus tea can help lower blood pressure in people with mild to moderate hypertension, as suggested by the 2020 international society of hypertension global hypertension practice guidelines 1. The guidelines mention that other beverages that can be beneficial for blood pressure include karkadé (hibiscus) tea, among others. Key points to consider when using hibiscus tea for blood pressure management include:
- Drinking 1-3 cups (8-24 ounces) of hibiscus tea daily
- Steeping dried hibiscus flowers (Hibiscus sabdariffa) in hot water for 5-10 minutes
- Consuming it without added sugar
- Consistently drinking it over several weeks The blood pressure-lowering effect of hibiscus tea is thought to come from anthocyanins and other polyphenols that act as ACE inhibitors, promote vasodilation, and have diuretic properties. While hibiscus tea is generally safe, it may interact with certain medications like hydrochlorothiazide and chloroquine, and should be used cautiously by people with diabetes or those on blood pressure medications as it might cause blood pressure to drop too low 1. It's essential to view hibiscus tea as a complement to, not a replacement for, conventional blood pressure treatments and lifestyle modifications, as recommended by the American Heart Association 1. Some lifestyle modifications that can help lower blood pressure include:
- Reducing salt intake
- Eating a healthy diet rich in whole grains, fruits, vegetables, polyunsaturated fats, and dairy products
- Moderating alcohol consumption
- Maintaining a healthy weight
- Engaging in regular physical activity
- Reducing stress and inducing mindfulness
- Avoiding or limiting consumption of high-salt foods and processed foods.
From the Research
Effect of Hibiscus Tea on Blood Pressure
- Hibiscus tea has been shown to have a positive effect on lowering blood pressure in patients with stage 1 hypertension 2.
- A randomized, double-blind, placebo-controlled clinical trial found that hibiscus tea consumption lowered systolic blood pressure in pre- and mildly hypertensive adults 3.
- However, a systematic review of four randomized controlled trials found that the evidence for the effectiveness of Hibiscus sabdariffa in treating primary hypertension was not reliable due to the poor quality of the studies 4.
Efficacy of Hibiscus Sabdariffa in Reducing Blood Pressure
- A systematic review and meta-analysis of 13 randomized controlled trials found that Hibiscus sabdariffa significantly reduced both systolic and diastolic blood pressure compared to placebo in patients with mild-to-moderate hypertension 5.
- Another review found that HS extracts have a low degree of toxicity and can act as a diuretic, and that animal studies have consistently shown that consumption of HS extract reduces blood pressure in a dose-dependent manner 6.
Comparison with Other Treatments
- Hibiscus tea was found to be as effective as the commonly used blood pressure medication Captropril, but less effective than Lisinopril 6.
- A systematic review and meta-analysis found that when Hibiscus sabdariffa was compared with active controls (antihypertensive drugs or other herbals), the change in systolic and diastolic blood pressure was not statistically significant 5.
Potential Mechanisms
- The antioxidant effects of anthocyanins, which are found in abundance in Hibiscus sabdariffa calyxes, are thought to be responsible for the antihypertensive and hypocholesterolemic effects 6.
- Other potential mechanisms include the inhibition of LDL-C oxidation, which impedes atherosclerosis, an important cardiovascular risk factor 6.