This dark green leafy schrub with a sweet/ bitter taste has many local names:
- “ewuro” – Yoruba (Nigeria)
- “onugbu” – Igbo (Nigeria)
- “shiwaka” or Chusar-doki – Hausa (across central and west Africa)
- “ndole” – Douala (Cameroon)
- “figatil” or “necroton” – Brazil
- “grawa” – Amharic (Ethiopia)
- “etidot” – Ibibios (Nigeria)
- “ityuna” – Tiv (Cameroon and Nigeria)
- “oriwo” – Edo (Nigeria)
- “mululuza” – Luganda (Uganda)
- “labwori” – Acholi (North Uganda and South Sudan)
- “olusia” – Luo (Kenya and Tanzania)
It can be grown anywhere. There are various species grouped under the genus Vernonia. Vernonia calvoana and Vernonia amygdalina are the types most common in west and east Africa, while Vernonia condensata is common in Brazil and other parts of central and south America. Other species are found in North America and Asia.
Species Found in Africa
– Vernonia amygdalina – Vernonia bamendae – Vernonia calvoana –
– Vernonia colorata – Vernonia galamensis – Vernonia staehelinoides –
The cooked leaves are a staple vegetable in soups and stews of various cultures throughout equatorial Africa. In Brazil it is mostly used for medicinal purposes. In Ethiopia, oils extracted from its seeds are used industrially in paints, coating plasticizers etc.
The most common specie in Africa is V. amygdalina
A study(1) revealed that Vernonia amygdalina leaf has high protein (33.3%), fat (10.1%), crude fibre (29.2%), ash (11.7%), mineral (Na, K, Ca, Mg, Zn & Fe), phytate (1015.4mg/100g) and tannin (0.6%) content, while it contain low cyanide (1.1mg/kg).
They are claims that it also contains Vitamin A, Vitamin C, Vitamin E, Vitamin B1 and Vitamin B2.
Phytochemicals extracted from V. amygdalina include saponins and alkaloids, terpenes, steroids, coumarins, flavonoids, phenolic acids, lignans, xanthones, anthraquinones, edotides and sesquiterpenes.
Bitter Leaf and Cancer
Extracts from bitter leaf have been proven to reduce blood estrogen level through suppression of aromatase activity in the body. This finding suggests bitter leaf could be helpful in the treatment of breast cancer. (2) Regular intake of bitter leaf may also lessen the risk of breast cancer, according to the February 2004 edition of Experimental Biology and Medicine. A recent study by Izevbigie et al. reproduced similar findings (3,4, 7).
In one study two organic extracts from Bitter Leaf (Vernodalin and Vernomygdin) were shown to kill cancer cells of the nose and throat region (10)
Essential Fatty Acids and Cardiovascular Disease
Bitter leaf contains linolenic acid (omega-3 fatty acid) and linoleic acid (omega-6 fatty acid), which are essential because the body is unable to make them. According to a study in the American Journal of Clinical Nutrition, when people consumed large quantities of linolenic and linoleic acid, they were at the lowest risk for cardiovascular disease when compared to those who did not. These fatty acids have been shown to protect against coronary heart disease, sudden cardiac death and heart failure, possibly through anti-arrhythmic (conditions affecting the heart rate), anti-thrombotic (against blood clot), anti-atherosclerotic (against hardening of blood vessels) and anti-inflammatory (against injury, irritation or infection) mechanisms, as reported in the 2009 issue of “Current Pharmaceutical Design”. Other benefits that the “Oxford Handbook of Clinical Medicine” attributes omega-3 fatty acids include control of arthritic conditions and protection against neurodegenerative diseases.
And bitter leaf produces these acids.
Effect on Malaria and Fever
Bitter juice has been used over centuries to treat a fevers especially related to malaria. In a preliminary clinical trial 25g fresh leaves of Bitterleaf was 67% effective in creating an adequate clinical response in African patients with mild falciparum malaria. (5) Of these 32% had complete parasite clearance. Unfortunately 71% of the patients had recurrence of symptoms. I wouldn’t advice to rely solely on bitter leaf juice against malaria, consult with your doctor.
Bitter leaf (V. amygdalina) may provide anti-oxidant benefits. (6) Anti-oxidants are substances which protect against cell damage. They thus help to reduces risk for serious diseases associated with oxidative stress like cancer, heart disease, stroke, aging, diabetes, arthritis, fibromyalgia, Parkinson’s Disease, Alzheimer’s, autoimmune diseases, cognitive decline, and eye conditions like macular degeneration.
Cytokines and Immune System
Cytokines are signalling molecules that aid cells to move towards areas of injury, irritation or infection during immune response. They are very important for the immune system. Many studies have shown that Bitter Leaf (V. amygdalina) extracts may strengthen the immune system through many cytokines (including NFҡB, pro inflammatory molecule) regulation.
Studies conducted using laboratory animals showed that bitter leaf decreased blood glucose by 50% compared to untreated diabetic animals. (8)
Against Worms and Other Parasites
This is one of the oldest traditional uses of bitter leaf juice , either from leaves, stem or roots. Scientific studies reveal that extracts of V. amygdalina possess in vitro anthelminthic (against worms) and anti-parasitic (against parasites) properties. (9)
Bitter leaf extract decreased bad (LDL) cholesterol by nearly half, while simultaneously raising good (HDL) cholesterol levels in studies using animals. There are no studies, however, providing similar effects in humans. However this claim has been made by many health experts.
The use of bitter leaf to treat various skin diseases like eczema and ringworm. This could be due to its anti-inflammatory effects
I think bitter leaf should be used more complementary not as a primary treatment.
(1) Nutr Health. 2006;18(2):151-60. Nutritive value and haemolytic properties (in vitro) of the leaves of Vernonia amygdalina on human erythrocyte. Oboh G1.
(2) Blanco JG, Gil RR, Bocco JL, Meragelman TL, Genti-Raimondi S, Flurry A. (2001). J Pharmacol Exp. Ther. 297
(3) Cimanga RK, Tona L, Mesia K, Musuamba CT, De Bruyne T, Apers S, Hernan N, Miert VS, Pieters L, Totte J, Vlietink AJ. In vitro antiplasmodia acivity of extravts and fractions of seven medicinal plants used in the democratic republic of Congo. J. Ethnopharmacol. 2004;93:27–32. [PubMed]
(4)Izevbigie EB, Bryant JL, Walker A. A novel natural inhibitor of extracellular signal-regulated kinases and human breast cancer cell growth. Exp. Biol. Med. 2004;229:163–169. [PubMed]
(5)Challand S, Willcox M (2009). “A clinical trial of the traditional medicine Vernonia amygdalina in the treatment of uncomplicated malaria”. J Altern Complement Med 15 (11): 1231–7. doi:10.1089/acm.2009.0098. PMID 19922255
(6)Erasto P, Grierson DS, Afolayan AJ. (2007). “Evaluation of Antioxidant activity and the fatty acid profile of the leaves of Vernonia amygdalina growing in South Africa”. Food Chemistry 104: 636–642. doi:10.1016/j.foodchem.2006.12.013.
(7)Sweeney CJ, Mehrotra S, Sadaria MR, Kumar S, Shortle NH, Roman Y, Sheridan C, Campbell RA, Murray DJ, Badve S, Nakshatri H (2005). “The sesquiterpene lactone parthenolide in combination with docetaxel reduces metastasis and improves survival in a xenograft model of breast cancer”. Mole. Cancer Ther 4 (6): 1004. doi:10.1158/1535-7163.mct-05-0030.
(8) Nwanjo HU (2005). “Efficacy of aqueous leaf extract of Vernonia amygdalina on plasma lipoprotein and oxidative status in diabetic rat models”. Nigerian J Physiological Sciences 20 (1-2): 30–42.
(9)Ademola IO, Eloff JN (February 2011). “Anthelminthic activity of acetone extract and fractions of Vernonia amygdalina against Haemonchus contortus eggs and larvae”. Trop Anim Health Prod 43 (2): 521–7. doi:10.1007/s11250-010-9727-7.
(10) Kupchan SM, Hemmnigway RJ, Karim A, Werner D. Tumor inhibitors. XLVII Vernodalin and Vernomygdin. Two new cytotoxic sesquiterpene lactones from Vernonia amygdalina Del. J. Org. Chem. 1969;34:3908–3911. [PubMed]