A small green bitter melon (front) and a scoop of Okinawan stir-fried gōyā chanpurū (back)
Bitter gourd (boiled, drained, no salt)
Nutritional value per 100 g (3.5 oz)
79 kJ (19 kcal)
- Dietary fiber
Vitamin A equiv.
6 μg (1%)
Thiamine (vit. B1)
0.051 mg (4%)
Riboflavin (vit. B2)
0.053 mg (4%)
Niacin (vit. B3)
0.280 mg (2%)
0.041 mg (3%)
Folate (vit. B9)
51 μg (13%)
0 μg (0%)
33.0 mg (40%)
0.14 mg (1%)
4.8 μg (5%)
9 mg (1%)
0.38 mg (3%)
16 mg (5%)
36 mg (5%)
319 mg (7%)
6 mg (0%)
0.77 mg (8%)
Bitter melon is generally consumed cooked in the green or early yellowing stage. The young shoots and leaves of the bitter melon may also be eaten as greens.
Bitter melon has been used in various Asian and African traditional medicine systems for a long time. In Turkey it has been used as a folk remedy for a variety of ailments, particularly stomach complaints. The fruit is broken up and soaked in either olive oil or honey.
Bitter melon is used as a folk medicine to treat gastrointestinal diseases, and extracts have shown activity in vitro against the nematode worm Caenorhabditis elegans.
Bitter melon is traditionally regarded in Asia as useful for preventing and treating malaria. Tea from its leaves is used for this purpose. Bitter melons are boiled and stir-fried with garlic and onions. This popular side dish known as corilla is served to prevent malaria. Laboratory studies have confirmed that species related to bitter melon have anti-malarial activity.
The plant is traditionally used against viral diseases such as chickenpox and measles. Tests with leaf extracts have shown in vitro activity against the herpes simplex type 1 virus, apparently due to unidentified compounds other than the momordicins.
Laboratory tests suggest that compounds in bitter melon might be effective for treating HIV infection. As most compounds isolated from bitter melon that impact HIV have either been proteins or lectins, neither of which are well-absorbed, it is unlikely that oral intake of bitter melon will slow HIV in infected people. It is possible oral ingestion of bitter melon could offset negative effects of anti-HIV drugs, if a test tube study can be shown to be applicable to people.
Studies in mice indicate that bitter melon seed may have a cardioprotective effect by down-regulating the NF-κB inflammatory pathway.
In 1962, Lolitkar and Rao extracted from the plant a substance, which they called charantin, which had hypoglycaemic effect on normal and diabetic rabbits. Another principle, active only on diabetic rabbits, was isolated by Visarata and Ungsurungsie in 1981. Bitter melon has been found to increase insulin sensitivity. In 2007, a study by the Philippine Department of Health determined that a daily dose of 100 mg per kilogram of body weight is comparable to 2.5 mg/kg of the anti-diabetes drug glibenclamide taken twice per day. Other compounds in bitter melon have been found to activate the AMPK, the protein that regulates glucose uptake (a process which is impaired in diabetics).
Bitter melon also contains a lectin that has insulin-like activity due to its non-protein-specific linking together to insulin receptors. This lectin lowers blood glucose concentrations by acting on peripheral tissues and, similar to insulin's effects in the brain, suppressing appetite. This lectin is likely a major contributor to the hypoglycemic effect that develops after eating bitter melon.
Two compounds extracted from bitter melon, α-eleostearic acid (from seeds) and 15,16-dihydroxy-α-eleostearic acid (from the fruit) have been found to induce apoptosis of leukemia cells in vitro. Diets containing 0.01% bitter melon oil (0.006% as α-eleostearic acid) were found to prevent azoxymethane-induced colon carcinogenesis in rats.
Researchers at Saint Louis University claim that an extract from bitter melon, commonly eaten and known as karela in India, causes a chain of events which helps to kill breast cancer cells and prevents them from multiplying.
Bitter melon has been used in traditional medicine for several other ailments, including dysentery, colic, fevers, burns, painful menstruation, scabies and other skin problems. It has also been used as abortifacient, for birth control, and to help childbirth.
The seeds of bitter melon contains vicine and therefore can trigger symptoms of favism in susceptible individuals. In addition, the red arils of the seeds are reported to be toxic to children, and the fruit is contraindicated during pregnancy.
The plant contains several biologically active compounds, chiefly momordicin I and II, and cucurbitacin B. The plants contains also several bioactive glycosides (including momordin, charantin, charantosides, goyaglycosides, momordicosides) and other terpenoid compounds (including momordicin-28, momordicinin, momordicilin, momordenol, and momordol). It also contains cytotoxic (ribosome-inactivating) proteins such as momorcharin and momordin.