Drinking hibiscus tea over a period of 2 to 6 weeks may help lower blood pressure in patients with elevated blood pressure. Other benefits may include lowered cholesterol and treatment of irritated stomach. However, there is insufficient scientific evidence to support these claims as of 2015.
The hibiscus flower, taken as a tea, is a traditional remedy for ailments, including colds, inflammation of the upper respiratory tract, heart and nerve diseases and constipation. These benefits are supported by anecdotal evidence. Small, preliminary studies have indicated that hibiscus may be beneficial for reducing blood pressure in patients with mild hypertension.
A small amount of research has been carried out to determine if hibiscus helps to lower cholesterol. However, the results of these studies are inconclusive. There is insufficient data to support the tea's effectiveness in treating stomach irritation, constipation, loss of appetite and heart disease.
Hibiscus is generally safe when consumed in food or as a tea. In medicinal amounts, its possible side effects are not yet known. Because there is some evidence that consumption of hibiscus triggers menstruation, pregnant women are advised not to take hibiscus, as it may cause a miscarriage. Individuals with diabetes and low blood pressure should consult a doctor before taking hibiscus as a supplement.
The hibiscus is an annual plant well known in Middle Eastern countries for its restorative properties and is used to make hibiscus tea. The tea is known as "karkade" in Egypt, but may also be known as "sour tea" in Iran. In Egypt, Sudan and other parts of North Africa, the tea is used to help achieve a normal body temperature, manage heart health and maintain balanced fluids. Treating upper respiratory problems is also a common use, and people also apply it in a topical manner for skin health. Outside of Africa, use as a laxative and for upper respiratory issues is common.