Bitter Melon
Botanical name: Momordica charantia
Parts used and where grown
Bitter melon grows in tropical areas, including parts of East Africa, Asia, the Caribbean, and South America, where it is used as a food as well as a medicine. The fruit of this plant lives up to its name—it tastes bitter. Although the seeds, leaves, and vines of bitter melon have all been used, the fruit is the safest and most prevalent part of the plant used medicinally.
Bitter melon has been used in connection with the following conditions (refer to the individual health concern for complete information):
Historical or traditional use (may or may not be supported by scientific studies)
Being a relatively common food item, bitter melon was traditionally used for an array of conditions by people in tropical regions. Numerous infections, cancer, and diabetes were among the most common conditions it has been purported to improve.1 The leaves and fruit have both been used in the Western world to make teas and beer or to season soups.
Active constituents
At least three different groups of constituents in bitter melon have been reported to have blood-sugar lowering actions of potential benefit in diabetes mellitus. These include a mixture of steroidal saponins known as charantin, insulin-like peptides, and alkaloids. It is still unclear which of these is most effective, or if all three work together. Some clinical trials have confirmed the benefit of bitter melon for people with diabetes.2
In traditional herbal medicine, bitter melon—like other bitter-tasting herbs—is thought to stimulate digestive function and improve appetite. This has yet to be tested in human studies.
How much is usually taken?
For those with a taste or tolerance for bitter flavor, a small melon can be eaten as food, or up to 3 1/3 ounces (100 ml) of a decoction or 2 ounces (60 ml) of fresh juice can be drunk per day.3 Though still bitter, tinctures of bitter melon (1 teaspoon [5 ml] two to three times per day) are also sometimes used. The amounts recommended would be appropriate for people with diabetes.
Are there any side effects or interactions?
Ingestion of excessive amounts of bitter melon juice (several times more than the amount recommended above) can cause abdominal pain and diarrhea.4 Excessive ingestion of the seeds had been associated with headache, fever, and coma. Bitter melon is not recommended for pregnant women. People with hypoglycemia (low blood sugar) should not take bitter melon, because it may trigger or worsen the problem. This effect has been reported in two young children and one adult patient with diabetes.
At the time of writing, there were no well-known drug interactions with bitter melon.
References
1. Duke JA. CRC Handbook of Medicinal Herbs. Boca Raton, FL: CRC Press, 1985, 315–6.
2. Raman A, Lau C. Anti-diabetic properties and phytochemistry of Momordica charantia L (Curcurbitaceae). Phytomed 1996;2:349–62.
3. Werbach MR, Murray MT. Botanical Influences on Illness. Tarzana, CA: Third Line Press, 1994, 139–41.
4. Brown DJ, Gaby A, Reichert R, Yarnell E. Phytotherapeutic and nutritional approaches to diabetes mellitus. Quart Rev Nat Med 1998;Winter:329–54.