Gymnema sylvestre Common name: Gymnema, Gurmar (in Hindi means “sugar destroyer”)
Part used: Leaf
Constituents: Resin, saponins (gymnemic acids), polypeptide gurmarin, stigmasterol, quercitol, and the amino acid derivatives betaine, choline and trimethylamine.
Actions: Diuretic, astringent, hypoglycemic agent and tonic.
Pharmacology: This herb’s anti-diabetic activity appears to be due to a combination of mechanisms. Two animal studies on diabetic rats found Gymnema extracts doubled the number of insulin-secreting beta cells in the pancreas and returned blood sugars to almost normal. Gymnema increases the activity of enzymes responsible for glucose uptake and utilization, and inhibits peripheral utilization of glucose by somatotrophin and corticotrophin. Plant extracts have also been found to inhibit epinephrine- induced hyperglycemia.
The primary clinical application for this botanical is as an anti-diabetic agent, especially in the early stages. If taken consistently for a year or more, it will help to prevent the condition from deteriorating. Gymnema may help to regenerate cells in the pancreas which secrete insulin, so it may be possible to control or reverse mild diabetes with diet and gymnema. The plant’s ability to block sweet tastes means that it can reduce sugar craving and contribute to weight loss programs.
Dosage and Toxicity
Contraindications: None known
Toxicity: No significant adverse effects have been reported, aside from the expected hypoglycemia. Safety in pregnancy has not been established.
Gymnema has been the object of considerable research since the 1930s, with promising results for types 1 and 2 diabetes.
In a controlled study, a standardized Gymnema extract was given to 27 type 1 diabetics at a dose of 400 mg daily for 6-30 months. Thirty-seven others continued on insulin therapy alone and were tracked for 10-12 months. Insulin requirements were decreased by about one-half and the average blood glucose decreased from 232 mg/dL to 152 mg/dL in the Gymnema group. The control group showed no significant decreases in blood sugar or insulin requirement. In addition, there was a statistically significant decrease in glycosylated hemoglobin (HbA1c) after 6-8 months on Gymnema when compared to either the pretreatment levels or the control group.
Twenty-two type 2 diabetics were administered 400 mg Gymnema extract daily for 18-20 months in addition to their oral hypoglycemic medications. This group experienced significant decreases in average blood sugar and HbA1c, and an increase in pancreatic release of insulin. Medication dosages were decreased, and five were able to discontinue drugs entirely.