Hibiscus tea, made from the calyces of Hibiscus sabdariffa, is consumed in many parts of the world, including Egypt, Sudan, Mexico and other tropical and subtropical regions. The plant is also known as roselle, karkade and sorrel in different countries.
The tea has attracted scientific interest because Hibiscus sabdariffa contains compounds including anthocyanins, polyphenols and organic acids. Research in humans has mainly examined its potential effects on blood pressure and other cardiovascular risk factors.
1. It may lower blood pressure
The best-established potential health benefit of hibiscus tea is its effect on blood pressure.
A 2020 systematic review and meta-analysis of seven randomized clinical trials involving 362 adults found that consumption of sour tea made from Hibiscus sabdariffa was associated with average reductions of about 4.7 mmHg in systolic blood pressure and 4.1 mmHg in diastolic blood pressure.
A larger 2022 meta-analysis involving 13 randomized controlled trials and 1,205 participants also found that Hibiscus sabdariffa reduced systolic and diastolic blood pressure compared with placebo among people with mild to moderate hypertension. However, it was not shown to be superior to conventional blood-pressure medicines.
An earlier randomized trial involving 65 adults with prehypertension or mild hypertension found that participants who drank three 240-milliliter servings of hibiscus tea daily for six weeks had a greater reduction in systolic blood pressure than those given a placebo beverage.
These findings do not mean that hibiscus tea can replace prescribed treatment for hypertension. The studies used different preparations, amounts and treatment periods, and researchers say further studies are needed to establish the most effective dose and duration.
2. Its effect on cholesterol is less certain
Hibiscus has also been studied for its potential effect on cholesterol.
The evidence, however, is mixed. A 2013 systematic review of six randomized trials involving 474 participants found no significant overall effect of Hibiscus sabdariffa on total cholesterol, LDL cholesterol, HDL cholesterol or triglycerides.
Other reviews have reported reductions in LDL and total cholesterol in some groups. A 2020 meta-analysis of nine trials involving 503 people with metabolic syndrome or related conditions found reductions in total and LDL cholesterol, but the researchers said more high-quality clinical trials were needed to confirm the findings.
A later review similarly found a modest reduction in LDL cholesterol but said more research was needed to establish the size and consistency of the effect.
For that reason, hibiscus tea should not be described as a proven treatment for high cholesterol.
3. It contains antioxidant compounds
Hibiscus calyces contain anthocyanins, polyphenols and other compounds with antioxidant activity. Antioxidants are substances that can help protect cells from oxidative damage.
Laboratory and animal studies have identified antioxidant effects from compounds in Hibiscus sabdariffa, but findings from laboratory research should not automatically be interpreted as proof that drinking the tea prevents disease in people.
Cardiovascular disease remains the leading cause of death worldwide. The World Health Organization estimates that cardiovascular diseases caused 19.8 million deaths in 2022, accounting for about 32% of all deaths globally.
Hibiscus tea may therefore be of interest as part of a healthy diet, but it is not a substitute for established measures such as a balanced diet, physical activity, avoiding tobacco and appropriate medical treatment.
How hibiscus tea is prepared
Hibiscus tea is generally made from the dried calyces of Hibiscus sabdariffa. The calyces can be prepared as hot or cold beverages and are also used traditionally in foods and drinks in countries including Egypt, Sudan and Mexico.
The exact strength of the drink varies considerably between products and studies. Because clinical trials have used different preparations and doses, there is no single evidence-based recipe that can be presented as the medically recommended amount for everyone.
What to know about safety
Hibiscus preparations have generally been well tolerated in the clinical studies reviewed, although mild gastrointestinal symptoms have been reported. Researchers have also raised questions about possible interactions between hibiscus and medicines, particularly because the herb may affect blood pressure and potentially interact with some drugs.
People taking medication, particularly for blood pressure or other chronic conditions, should discuss regular use of concentrated hibiscus preparations with a health professional rather than using the tea to replace prescribed treatment.
Evidence on the safety of hibiscus during pregnancy is also limited. Because herbal products can have uncertain effects during pregnancy and may interact with medicines, pregnant people should seek medical advice before using hibiscus as a herbal remedy.
The available evidence suggests that hibiscus tea can be a reasonable beverage for many people, but claims about its health effects should remain proportionate to the evidence. Its potential effect on blood pressure is supported by clinical research, while claims about cholesterol and disease prevention require more study.
