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Bitter melon is a very bitter remedy with a wonderful healing effect throughout the body

Bitter melon

Momordica charantia Cucurbitaceae

Bitter melon, also known as karavella, is a common vegetable used to regulate blood sugar levels and treat urinary disorders.

Sustainability Status

Sustainability status

Not currently on risk lists but complete data may be missing on the status of the species. Read more about our sustainability guide.

Key benefits
  • Regulate blood sugar levels
  • Treats urinary disorders
  • How does it feel?

    Karavella is a tender perennial flowering climber of family cucurbitaceae, which grows in tropical areas, including parts of East Africa, the Caribbean and South America. The leaf blades are 5 – 12 cm in diameter, with 3 -7 deeply separated lobes, which are mostly blunt, but have small marginal points. Flowers are monoecious and yellow in colours; each plant bears separate yellow short male and long female flowers. The fruit has ovoid, ellipsoid or spindle shaped, 2.5 -7 cm long with tapering ends, green or yellowish in colour. Seeds in size 8 – 13mm are long compressed, corrugate on the margin, sculptured on both faces.

  • What can I use it for?

    Bitter melon has been used in the folk medicine from ancient times; in Ayurveda, various parts of the plant are recommended for many diseases as it contains an array of biologically active compounds including triterpens, proteins, steroids, alkaloids, saponinins and flavonoids due to which plant possess hypoglycemic, anti-fungal, anti-bacterial and anti-viral properties.

    Traditionally, this plant is used for treating diabetes thanks to its blood sugar lowering effect; it can also increase the glucose uptake and glycogen synthesis in the liver, muscles and fat cells. Extract of various plant parts of Karavella have been shown to have anti-microbial and anti-viral activities, resulting useful in case of intestinal parasitic infections. The plant can be also used for treating urinary stones, clearing bile from the liver, helping to reduce inflammatory skin conditions as well.

  • Into the heart of bitter melon

    Anti-diabetic propertis are mainly due to a mixture of steroidal sapogenins (known as Charatin), which are responsible for the hypoglycemmic action, and a polypeptide (known as P-Insulin), which can decrease and normalize the blood sugar level.

    Its extracts have been shown to prevent infection by numerous bacteria and parasitic organisms, acting as an anthelmintic in the intestines and reducing inflammations in the digestive system. In particular, the plant was found more effective in the treatment of Ascaridia galli.

    Bitter Melon can also inhibit infection and growth of several viruses, including Herpes simplex.

    Bitter melon has been reported to have a significant anti-urolithic activity in vitro studies; the results show that the plant has a consistent crystal inhibition action, probably because of the presence of saponin.

    Bitter melon has become renowned for its anti-diabetic properties. Charantin is an effective hypo-glycaemic and the polypeptide P lowers blood sugar levels more effectively than insulin without some of the side effects. The bitter principle clears the kapha that is obstructing the pancreatic function and stimulates medavdhatuagni to metabolise fats and sugars efficiently. It reduces blood and urine sugar levels by reducing insulin resistance.

    It acts as an anthelmintic in the intestines. It has the added vermicidal effect of flushing bacterial and parasitic infections from the intestines as it mildly purges the bowel. It also reduces inflammation in the intestines. A special quality of bitter melon is that it does not aggravate vata, which is rare for a bitter substance.

    Its effect on the water channels (ambhuvahasrotas) helps to clear kapha from the system. It can be included in a formula for urinary stones as it has a direct effect on the urinary channel (mutravahasrotas).

    Its alterative nature treats inflammatory skin conditions and benefits bhrajaka pitta. Having a thorough effect on the detoxifying capabilities of the whole system it regulates ranjaka pitta, clears bile from the liver, acid via the urine and toxaemia via the bowel.

    It has an affinity for the blood. It is a traditional remedy for anaemia as it stimulates the tissue fires (dhatavagni) to work at optimum efficiency. It helps to build haemoglobin count by enhancing absorption.

  • Traditional actions

  • Traditional energetic actions

    Herbal energetics are the descriptions Herbalists have given to plants, mushrooms, lichens, foods, and some minerals based on the direct experience of how they taste, feel, and work in the body. All traditional health systems use these principles to explain how the environment we live in and absorb, impacts our health. Find out more about traditional energetic actions in our article “An introduction to herbal energetics“.

  • Did you know?

    • This annual creeper is cultivated all over India for its fruiting vegetables.
    • Although it is bitter it does not aggravate vata (tiktamvatalam).
    • Successful clinical trials have used the equivalent of 60ml of the fresh juice/day.
    • The leaves and fruit have both been used to make teas and beer, or to season soups in the Western world.

Additional information

  • Safety

    Caution in patients on hypoglycaemic medication.

  • Dosage

    Tincture: 3–15ml of a 1:2 at 40% fresh tincture

    Dried: 5–10g/day

An ‘aromatic’ remedy, high in volatile essential oils, was most often associated with calming and sometimes ‘warming’ the digestion. Most kitchen spices and herbs have this quality: they were used both as flavouring and to ease the digestion of sometimes challenging pre-industrial foods. Many aromatics are classed as ‘carminatives’ and are used to reduce colic, bloating and agitated digestion. They also often feature in respiratory remedies for colds, chest and other airway infections. They are also classic calming inhalants and massage oils, and are the basis of aromatherapy for their mental benefits.
Astringent taste
The puckering taste you get with many plants (the most familiar is black tea after being stewed too long, or some red wines) is produced by complex polyphenols such as tannins. Tannins are used in concentrated form (eg from oak bark) to make leather from animal skins. The process of ‘tanning’ involves the coagulation of relatively fluid proteins in living tissues into tight clotted fibres (similar to the process of boiling an egg). Tannins in effect turn exposed surfaces on the body into leather. In the case of the lining of mouth and upper digestive tract this is only temporary as new mucosa are replenished, but in the meantime can calm inflamed or irritated surfaces. In the case of open wounds tannins can be a life-saver – when strong (as in the bark of broadleaved trees) they can seal a damaged surface. One group of tannins, the reddish-brown ‘condensed tannins’ are procyanidins, which can reduce inflammation and oxidative damage.
Bitters are a very complex group of phytochemicals that stimulate the bitter receptors in the mouth. They were some of the most valuable remedies in ancient medicine. They were experienced as stimulating appetite and switching on a wide range of key digestive functions, including increasing bile clearance from the liver (as bile is a key factor in bowel health this can be translated into improving bowel functions and the microbiome). Many of these reputations are being supported by new research on the role of bitter receptors in the mouth and elsewhere round the body. Bitters were also seen as ‘cooling’ reducing the intensity of some fevers and inflammatory diseases.
Blue-purple colouring
Any fruits with a blue-purple colouring contain high levels of the polyphenols known as anthocyanins. These work 1) on the walls of small blood vessels, helping to maintain capillary structure to reduce a key stage in inflammation, and improving the microcirculation to the tissues; 2) to improve retinal function and vision; 3) to support connective tissue repair around the body.
Traditional ‘cold’ or cooling’ remedies often contain bitter phytonutrients such a iridoids (gentian), sesiquterpenes (chamomile), anthraquinones (rhubarb root), mucilages (marshmallow), some alkaloids and flavonoids. They tend to influence the digestive system, liver and kidneys. Cooling herbs do just that; they diffuse, drain and clear heat from areas of inflammation, redness and irritation. Sweet, bitter and astringent herbs tend to be cooling.
Traditional ‘hot’ or ‘heating’ remedies, often containing spice ingredients like capsaicin, the gingerols (ginger), piperine (black or long pepper), curcumin (turmeric) or the sulfurous isothiocyanates from mustard, horseradich or wasabi, generate warmth when taken. In modern times this might translate as thermogenic and circulatory stimulant effects. There is evidence of improved tissue blood flow with such remedies: this would lead to a reduction in build-up of metabolites and tissue damage. Heating remedies were used to counter the impact of cold, reducing any symptoms made worse in the cold. .
Mucilages are complex carbohydrate based plant constituents with a slimy or ‘unctuous’ feel especially when chewed or macerated in water. Their effect is due simply to their physical coating exposed surfaces. From prehistory they were most often used as wound remedies for their soothing and healing effects on damaged tissues. Nowadays they are used more for these effects on the digestive lining, from the throat to the stomach, where they can relieve irritation and inflammation such as pharyngitis and gastritis. Some of the prominent mucilaginous remedies like slippery elm, aloe vera and the seaweeds can be used as physical buffers to reduce the harm and pain caused by reflux of excess stomach acid. Mucilages are also widely used to reduce dry coughing. Here the effect seems to be by reflex through embryonic nerve connections: reduced signals from the upper digestive wall appear to translate as reduced activity of airway muscles and increased activity of airway mucus cells. Some seed mucilages, such as in psyllium seed, flaxseed (linseed) or guar bean survive digestion to provide bulking laxative effects in the bowel. These can also reduce rate of absorption of sugar and cholesterol. .
New-mown hay aroma
The familiar country odour of haymaking, of drying grass and other plants, is largely produced by coumarins (originally isolated from tonka beans – in French coumarou) and widely used in perfumery. They are chemically categorised as benzopyrone lactones and are important phytochemicals, with strong antioxidant activity in the laboratory and likely effects in modulating inflammation. They were most often associated with the calming effect linked to their use in stuffing mattresses and pillows and plants, high In coumarins were commonly used for these properties.
Resins are most familiar as tacky discharges from pine trees (and as the substance in amber, and rosin for violin bows). They were most valued however as the basis of ancient commodities like frankincense and myrrh (two of the three gifts of the Three Wise Men to the baby Jesus) and getting access to their source was one benefit to Solomon for marrying the Queen of Sheba (now Ethiopia). Resins were the original antiseptic remedies, ground and applied as powders or pastes to wounds or inflamed tissues, and were also used for mummification. With alcohol distillation it was found that they could be dissolved in 90% alcohol and in this form they remain a most powerful mouthwash and gargle, for infected sore throats and gum disease. They never attracted much early research interest because they permanently coat expensive glassware! For use in the mouth, gums and throat hey are best combined with concentrated licorice extracts to keep the resins in suspension and add extra soothing properties. It appears that they work both as local antiseptics and by stimulating white blood cell activity under the mucosal surface. They feel extremely effective!
The salty flavour is immediately distinctive. A grain dropped onto the tongue is instantly moistening and a sprinkle on food enkindles digestion. This easily recognisable flavour has its receptors right at the front of the tongue. The salty flavor creates moisture and heat, a sinking and heavy effect which is very grounding for the nervous system and encourages stability. People who are solid and reliable become known as ‘the salt of the earth'.
The sharp taste of some fruits, and almost all unripe fruits, as well as vinegar and fermented foods, is produced by weak acids (the taste is generated by H+ ions from acids stimulating the sour taste buds). Sour taste buds are hard-wired to generate immediate reflex responses elsewhere in the body. Anyone who likes the refreshing taste of lemon or other citrus in the morning will know that one reflex effect is increased saliva production. Other effects are subjective rather than confirmed by research but there is a consistent view that they include increased digestive activity and contraction of the gallbladder.
In the days when most people never tasted sugar, ‘sweetness’ was associated with the taste of basic foods: that of cooked vegetables, cereals and meat. In other words sweet was the quality of nourishment, and ‘tonic’ remedies. Describing a remedy as sweet generally led to that remedy being used in convalescence or recovery from illness. Interestingly, the plant constituents most often found in classic tonics like licorice, ginseng are plant steroids including saponins, which also have a sweet taste.

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