Hibiscus is a large genus of flowering plants, growing primarily in tropical and subtropical regions, whose flowers are used for a wide range of medicinal purposes and edible products ranging from making jams and jellies to lowering blood pressure, aiding in weight loss, reducing cholesterol and, in some cases, treating cancer. Flowers from the Hibiscus sabdariffa are generally consumed by brewing a medicinal tea or eaten in salads. Like many herbal preparations, however, healing properties and potentially hazardous side effects are associated with the consumption of the plant. Certain precautions should be taken.
Effects on Estrogen
Consuming hibiscus tea lowers estrogen levels, and those using hormone replacement therapy (HRT) or taking birth control pills should avoid drinking the tea, according to research done by Guru Jambheshwar University of Science and Technology, India, and published in "eCAM," an alternative medicine journal.
Pregnancy and Fertility
Research on estrogen, pregnancy and fertility performed at the Guru Jambheshwar University of Science and Technology in India indicate the estrogenic qualities of the tea may interfere with healthy reproductive activity and affect childbearing and female fertility. Side effects from consuming hibiscus tea on fetuses are unclear.
Hibiscus tea lowers blood pressure, and has diuretic properties and mild effects on dilation of blood vessels, according to Maureen Williams, ND, of the Bastyr Center for Natural Health in Seattle, Washington. People with low blood pressure or those with hypertension who take blood-pressure-lowering medicines should avoid drinking the tea due to possible contradictory interactions between the tea and medications.
There are some early indications that hibiscus has an effect on cancerous cells in the brain and skin, based on research on medicinal plants from the Americas for the treatment of cancer and AIDS performed at the New York Botanical Garden, in coordination with the National Cancer Institute. Although this is good news, those taking anticancer drugs or who are undergoing radiation or chemotherapy should avoid the tea due to possible interactions between it and their medications.
Some people have experienced hallucinogenic effects from drinking hibiscus tea or a sensation of feeling intoxicated. Take care when driving or using machinery if you are unfamiliar with the side effects of this tea.