Gymnema sylvestre and diabetes

 Is Gymnema the future for diabetes treatment?

Gymnema sylvestre ___ an introduction!

It is a slow-growing medicinal woody climber found in central and peninsular India and an antidiabetic plant used in folk, ayurvedic and homeopathic medicines. It is known as Periploca of the woods in English, meshashringi in Sanskrit, waldschlinge in German; podapatri in Telugu, and gurmar in Hindi. All these names mean “destroyer of sugar”. Hooper in 1887 told that the leaves, when chewed, abolish the taste of sweetness. Power and Tutin identified the anti-saccharine property in a fraction called gymnemic acid.

Mechanism of action

According to “The Journal of clinical biochemistry and nutrition” several pharmacological actions of the herb helps it to induce hypoglycemic effects.

The herb has been known to stimulate insulin secretion from pancreatic beta-cells by increasing the cell membrane permeability. It increases absorption or utilization of glucose by insulin-dependent pathways, an increase in phosphorylase activity, and a decrease in gluconeogenic enzymes. It also causes inhibition of glucose absorption from the small intestine. The most unique action of the herb is its ability to decrease the perception of sweet taste. It was noted that after chewing its fresh leaves the sweetness was decreased for up to two hours. The components solely responsible for this effect are Gymnemic acids and Gurmarin. This effect occurs due to direct action on sensory efferent nerves that are responsible for the transmission of sweet taste.

Clinical trials:

The first scientific evidence that Gymnema control blood sugar was reported a century ago when researchers demonstrated that Gymnema leaves reduced glucosuria in diabetic rats. In this animal experiment, Gymnema leaf powder lowered both fasting and after-meal blood glucose levels.

 But it was an experiment done on animals how can we relate it to humans?

Well, two studies hold particular importance in the case of humans. One case consisted of about 27 type-1 diabetic patients who were given Gymnema extracts at a dose of 400 mg for 6 to 30 months another 37 diabetic patients were asked to carry on with insulin therapy and were tracked for 10 to 12 months.

In the experimental group, Gymnema extract decreased blood glucose level from 232mg/dl to 152mg/dl and even cut insulin requirements by half. On another hand no significant changes were observed in the control group.

A similar study involved 22 type-2 diabetic patients who were given 400mg Gymnema extracts daily in combination with their normal prescription drugs for 18 to 20 months. The extract was successful in decreasing blood sugar and HbA1c (glycated hemoglobin) and increasing insulin levels.

Forms and dosage:

Gymnema is most often available in the form of a dried extract of the leaves, it can be taken in the form of tea or capsules. It is usually standardized to 25% gymnemic acid. The dose most often advised, is 400 mg three times per day before meals. 

Safety concerns:

It is considered safe for most people, but it should not be taken by children and pregnant or lactating women. No adverse reactions have been observed until now.

Additional benefits:

In addition to treating diabetes, the herb also plays a role in controlling obesity, plasma glucose levels, and the accumulation of lipids in tissue, liver, and muscle. It is also used for the treatment of asthma, eye complaints, inflammations, and snakebite. In addition, it possesses antimicrobial property, can control high cholesterol levels, is a cough suppressant and, is hepatoprotective in nature.