Several scientific studies have established the potency of African bitterleaf (Vernonia amydalina) in reducing blood pressure with little or no side effects. The bitterleaf plant is indigenous to Africa and has been commonly used as traditional medicine for centuries. The herb is popularly known as bitterleaf due to its bitter taste. Water extracts of the leaves of Vernonia amygdalina have been used to treat a variety of ailments across Africa, including fever, malaria, diarrhoea, dysentery, hepatitis, symptoms of flu, body pain, headache, skin infections, stomach upset, constipation, and to induce fertility. Extracts from its roots are also used as medicine for the treatment of malaria, stomach problems, sexually transmitted diseases, diarrhoea, among others. In parts of Nigeria, crushed leaves are placed over wounds to prevent infection and facilitate healing.
We shall here present a review of some scientific research papers published by researchers who conducted studies on bitterleaf in different parts of the world. All the research papers tend to make one general conclusion: that bitterleaf contains compounds that can effectively work to reduce blood pressure in patients with high blood pressure.
High Blood Pressure among Africans
According to the World Health Organization, Africa has the highest number of sufferers of high blood pressure as about 46% of the adult population is clinically diagnosed to be hypertensive. This is outside of the many sufferers without access to clinical diagnosis and treatment. A study published in the Journal of Hypertension notes that “blood pressures in persons of African descent exceed those of other racial/ethnic groups in the US. Whether this trait is attributable to genetic factors in African-origin populations, or a result of inadequately measured environmental exposures, such as racial discrimination, is not known.” However, several reasons have been adduced for the statistically significant higher rate of high blood pressure in people of African descent, and these include low socio-economic status, increasing urbanization, unhealthy diet, stress, among others.
Before the race to acquire a Western-oriented lifestyle among Africans, traditional African societies did not suffer an increased rate of high blood pressure as Africans of today. It was a communalistic society where people functioned in communities; there was deep regard for human interactions, and interdependency was a given. Today, individualism is gradually seeping into different societies across Africa. The drive to gain more wealth, more degrees, or higher status has resulted in stress, a diminished sense of trust within communities, and individuals isolating themselves in pursuit of a narrowly defined meaning of success.
Preventing high blood pressure among Africans will start from a paradigm shift from acquisition for self to production for the community. But while that is being worked on, African bitterleaf or Vernonia amygdalina can help reverse the high blood pressure of many sufferers across the region.
Research on BitterLeaf (Vernonia Amygdalina)
In a research paper published in the Pharmaceutical Biology journal in 2017, bitterleaf extracts were obtained from fresh leaves and administered to laboratory mice suffering from high blood pressure in a measured dosage. The results obtained showed that ethanol extracts of bitterleaf can induce a reduction in high blood pressure in the subjects of study when compared to the control group.
Another study published in 2020 in the International Journal of Pharmaceutical Sciences and Research “demonstrated that the combination of the aqueous leaf extracts of bitterleaf” and another plant of African origin known as Ocimum gratissimum, “has [a] synergistic effect that might be of importance…in the management of salt-induced hypertension.”
In yet another study, published in the Journal of Food Biochemistry, researchers looked at the anti-diabetes and anti-hypertension properties of extracts of bitterleaf by administering the extracts in a dose-dependent manner on rats with the ailments. The study established that there exists a strong correlation between the enzymes contained in the extracts of bitterleaf in drastically reducing high blood pressure and even blood sugar in diabetic patients.
The final study we shall examine in this piece is published in the International Journal of Pharmaceutics and Drug Analysis. In the study, a group of researchers determined that “the leave extract of Vernonia amygdalina produced a significant decrease in blood pressure.” The scientists concluded that “based on our observations, we therefore conclude that the aqueous leave extract of Vernonia amygdalina produced significant reduction in cat blood pressure and could be used in the management of hypertension.”
Other researchers who examined bitterleaf plants for toxicity have also noted that the plant is safe for use even at high doses as it comes with insignificant toxicity to the human system. This differs significantly from the numerous drugs now prescribed for high blood pressure, which sometimes come with even worst side effects than the condition it is being used against.
The above studies, when combined with the folkloric use of bitterleaf as a blood-cleansing and blood pressure-reducing drug by African traditional medical practitioners, hold great potential for being mainstreamed in the management and treatment of high blood pressure among its numerous sufferers in Africa.
Bitterleaf is only one of the numerous herbs that exist within African traditional pharmacognosy, which might well hold the key to the treatment of the numerous diseases that plague humanity. Africans must begin to emphasize and mainstream these traditional herbs for the benefit of Africans and the rest of the world.
Dr Chika Ezeanya Esiobu holds a Certificate in Herbal Medicine from the University of Minnesota and a Doctorate in African Studies from Howard University. She is not a medical practitioner, so the contents of her writings should by no means replace accurate diagnosis and treatment by qualified medical personnel.