The hibiscus shrub is a flowering plant indigenous to tropical and subtropical regions. It produces mainly red flowers, which are used for a wide range of medicinal purposes. Hibiscus flowers are safe to eat directly, but they are more often consumed in jams, jellies and herbal teas. Some of the medicinal properties of hibiscus flowers include reducing cholesterol and blood pressure, stimulating weight loss, and possibly deterring cancer growth. However, the flowers and roots of the hibiscus plant can also affect estrogen levels, and women should be cautious when using them.
Most hibiscus species produce bright red flowers, the dried sepals of which are made into hot herbal infusions or cold beverages in a variety of countries, particularly India. Commercial varieties of hibiscus flower tea are readily available in North America. According to the “Natural Standard Herb & Supplement Reference,” hibiscus flower extract has shown the ability to reduce blood pressure, boost immunity, lower blood cholesterol and sugar levels, stimulate metabolism, affect hormone levels, and possibly deter against the proliferation of some forms of cancer. Hibiscus tea, being much more dilute than extracts, has less impact on your body.
Impact on Estrogen
According to a 1997 “Biological and Pharmaceutical Bulletin,” the extract of Hibiscus rosa-sinensis flowers causes irregular estrous cycles in mice because of increased production of estrogen and hormonal imbalance. The researchers concluded that the hormonal imbalance may prevent ovulation. Women do not go through estrus, but there remains a possibility that consuming hibiscus flowers can disrupt female cycles and cause difficulty with trying to conceive.
According to an Indian study published in a 2008 edition of the journal “Evidence-Based Complementary and Alternative Medicine,” ethanol extract of Hibiscus rosa-sinensis root displays strong estrogenic properties and near complete anti-implantation activity in animal studies and should be considered a strong anti-conceptive compound. In other words, hibiscus root extract promotes the synthesis of estrogen, which upsets hormonal balance and uterine development and prevents a fertilized egg from implanting and growing in the uterus. The doses used were 400 mg/kg of body weight, and it was 100 percent effective at preventing conception in the test mice. The estrogenic activity of the hibiscus roots is thought to be stronger than its leaves.
Various parts of the hibiscus shrub have been used by indigenous peoples as a form of birth control for hundreds of years, and scientific studies provide evidence for its effectiveness. The strength of commercially prepared hibiscus tea no doubt varies and possibly contains more parts of the plant than just its flowers. As such, women who are pregnant or are trying to get pregnant, or those who are using hormone replacement, should play it safe and avoid drinking hibiscus tea or consuming its extract. The effects of consuming hibiscus tea on fetuses are unclear, but they are potentially negative. Using hibiscus products as a form of birth control has not proven to be more effective or reliable than other conventional methods, so use caution and practice safe sex regardless of supplementation.
- “Natural Standard Herb & Supplement Reference: Evidence-based Clinical Reviews”; Catherine E. Ulbricht, et al.; 2005
- "Biological and Pharmaceutical Bulletin"; Effect of Benzene Extract of Hibiscus Rosa Sinensis on the Estrous Cycle and Ovarian Activity in Albino Mice; D.R. Murthy, et al.; July 1997
- "Evidence-Based Complementary and Alternative Medicine"; Post-Coital Antifertility Activity of Hibiscus Rosa-sinensis Linn. Roots; N. Vasudeva, et al.; March 2008