Bitter melon or bitter gourd is also known as karela in Hindi. As the name indicates, it is bitter in taste. Despite its taste, bitter gourd is a very popular and staple vegetable in Indian households. Bitter melon is also very significant in Ayurveda given its numerous health benefits.
Botanical Description of Bitter Melon or Bitter Gourd
- The botanical name of bitter melon or bitter gourd is Momordica charantia and it belongs to the Cucurbitaceae family.
- Bitter melon is an annual/perennial climber.
- It can reach 2–3 meters in height and can grow up to 5 meters in length.
- Bitter melon can be grown at high altitudes.
- Its stem is well-branched, slender, and green in color. It carries unbranched tendrils in the leaf axils.
- The leaves of bitter gourd are simple, alternate with 3–7 deeply separated lobes, and have an unpleasant smell when crushed.
- The flowers of bitter melon are yellow in color and the male and female flowers are separate.
- In the Northern Hemisphere, flowering occurs from June to July and fruiting from September to November.
- Fruits of the bitter melon are oblong or cylindrical in shape. They can be 2-10 cm in length. The fruits are covered with warts and longitudinal ridges.
However, the fruit of Chinese bitter melon is different from that of the typical Indian bitter melon. It is pale green in color and its surface has warts but they are not pointed like in the Indian variety.
Both varieties can be easily differentiated visually. The seeds are usually 8–15 mm long.
Sanskrit Synonyms of Bitter Melon1
Karavellaka: It is helpful in relieving fever and other conditions
Katilla: It spreads its properties
Varieties of Bitter Gourd2
According to the Ayurvedic text Dravyaguna Vijnana (Ayurvedic Herbology), bitter melons come in two varieties depending on their shape.
- Large bitter melon: Large varieties are called karavellaka. These generally grow during summer.
- Small bitter melon: Small varieties are called karavelli or karelli. They generally grow during monsoon.
Rasa or taste: Tikta or bitter, katu or pungent.
Guna or qualities: Laghu or light, ruksha or dry.
Virya or potency: Ushna or hot.
Vipaka or taste conversion after digestion: Katu or pungent.
Effect on dosha: Bitter melon is Kapha dosha and Pitta dosha shamak which means it pacifies aggravated Kapha and Pitta doshas. However, bitter gourd does not increase Vata dosha. Bitter melon benefits these doshas when they’re aggravated.2
Part of plant used and dosage: Fruit and whole plant.3 with a dosage for Swarasa or fresh juice being 10-20 ml.3
Bitter Melon Uses According to Dravyaguna Vijnana 2,3
- Skin disorders.
- Cleansing and healing wounds.
- Relieving burning sensation.
- Aids digestive strength.
- Bitter melon or bitter gourd is helpful in problems related to loss of taste.
- It is helpful in various problems related to Pitta dosha.
- It has a mild laxative effect and is useful for constipation.
- It is useful for treating worm infestations.
- It is useful in purifying the blood.
- It is helpful in relieving inflammation.
- It is useful in problems related to Kapha dosha.
- It may be helpful in diabetes and problems related to the urinary tract.
- It may be helpful in menstrual problems.
- It is useful for cleansing breast milk.
- Obesity may improve with use of bitter gourd.
- Bitter gourd may also be helpful in removing impurities from the body.
- The paste is used for various skin problems, wounds, and hemorrhoids.
- It is helpful in liver problems.
- It is useful in various blood-related problems.
- It is helpful in cough and cold.
- It is helpful in asthma and chronic respiratory problems.
Nutrient Profile of Bitter Gourd 4
Bitter melon contains many nutrients just like its many benefits. It includes bioactive chemicals, vitamins, minerals, and antioxidants.
The fruits of bitter melon contain high amounts of vitamin C, vitamin A, vitamin E, vitamins B1, B2, and B3, as well as vitamin B9 (folate).
The caloric values for leaf, fruit, and seed have been measured as 213.26, 241.66 and 176.61 Kcal/100 g respectively.
The fruit of bitter melon is also rich in minerals including potassium, calcium, zinc, magnesium, phosphorus, and iron. It is also a good source of dietary fiber.
The medicinal value of bitter melon comes from its high antioxidant properties because of its phenols, flavonoids, isoflavones, terpenes, anthroquinones, and glucosinolates, all of which confer a bitter taste.
The fruits consist of glycosides, saponins, alkaloids, reducing sugars, resins, phenolic constituents, fixed oil, and free acids.
The fruit pulp has soluble pectin but no free pectic acid. Research has found that the leaves are nutritious sources of calcium, magnesium, potassium, phosphorus, and iron; both the edible fruit and the leaves are great sources of the B vitamins.
Scientific Research and Benefits of Bitter Gourd (Bitter Melon)
Bitter melon or Karela has many benefits. These benefits have been further validated with scientific research.
Animal studies and human trials have shown that bitter melon has an antidiabetic effect.5
Oral administration of aqueous extracts has shown to lower glucose concentrations independently of intestinal glucose absorption and involved extrapancreatic effects.
It also plays a role in the renewal of β cells in STZ (streptozotocin)-diabetic rats or recovery of destroyed β cells.
Some studies have suggested that the antidiabetic mechanism of bitter melon extracts may be due to enhancing insulin secretion by the islets of Langerhans, reducing glycogenesis in liver tissue, enhancing peripheral glucose utilization and increasing serum protein levels.5
Studies suggested that bitter melon is a good natural source of antioxidants. Bitter gourd pulp and its extracts, followed by seed powder and its ethanol/water extracts exhibited stronger anti-oxygenic activity than other solvent extracts.5
Bitter gourd also possesses anti-viral activity. A variety of compounds isolated from Momordica charantia have antiviral activity.
Ethanolic extracts from leaves and stems of bitter melon highly inhibit HSV-1 and SINV viruses.5
Bitter melon also possesses anti-microbial effect.
The aqueous extract from bitter melon seed exhibited significant antimicrobial activity against several bacteria in the following ascending order: P. multocida, S. typhi, S. epidermidis, and L. bulgaricus.
As for the ethanolic extract, the sequence was S. aureus, M. luteus, E. coli, S. epidermidis, and L. bulgaricus, while n-hexane and petroleum ether extracts were effective against S. aureus.5
Some studies also suggest that it possesses anti-inflammatory properties. It’s one of the many benefits of Karela.
Karela also has anti-tumor activity.
Bitter melon extracts and its monomer components have shown strong anticancer activity against various tumors such as lymphoid leukemia, lymphoma, choriocarcinoma, melanoma, breast cancer, skin cancer, and prostate cancer.5
It also possesses hypolipidemic activity. A study done on rats for 30 days showed that the cholesterol level was reduced after they were given Momordica charantia.5
It also has immunomodulatory activity.5
It possesses wound healing activity.5
The fruit extract of bitter melon has been demonstrated to possess activity against H. pylori, which could induce stomach ulcers.5
Studies also reported that bitter melon has anthelmintic activity against a variety of helminths like Ascaris summ, Ascaridia galli, Fasciola hepatica, Stellantchasmus falcatus, Strongyloides sp. and Caenorhabditis elegans.6
Anthelmintics are helpful in expelling helminths or parasitic worms from the body. This suggests that bitter melon is beneficial for keeping the digestive tract clean.
Bitter Gourd Side Effects
This plant is basically harmless to the human body under normal conditions, however, it may induce adverse reactions due to differences in uptakes, processing methods, physical differences, health conditions, and other factors.
Consult your Ayurvedic practitioner or health care provider before introducing bitter melons into your diet.
- Aadrash Nighantu, vol. 1, page no.638, by Shri Bapalal Vaidya, Chaukhmbha Bharti Academy,2013.
- Dravyaguna Vijnana by Aacharya Priyavrat Sharma, Volume 2, page no.684, Chaukhamba Bharati Academy, 2017
- Dravyaguna Vijnana by Aacharya Priyavrat Sharma, Volume 2, page no.685, Chaukhamba Bharati Academy, 2017
- Joseph, Baby and D Jini. “Antidiabetic effects of Momordica charantia (bitter melon) and its medicinal potency” Asian Pacific Journal of Tropical Disease vol. 3,2 (2013): 93–102.
- Jia, Shuo et al. “Recent Advances in Momordica charantia: Functional Components and Biological Activities” International journal of molecular sciences vol. 18,12 2555. 28 Nov. 2017, doi:10.3390/ijms18122555
- Poolperm, Sutthaya, and Wannee Jiraungkoorskul. “An Update Review on the Anthelmintic Activity of Bitter Gourd, Momordica charantia” Pharmacognosy reviews vol. 11,21 (2017): 31-34.