New human clinical trial backs Gymnema Silvestre’s diabetes benefits

August 03, 2010

   A new human clinical trial of an extract of the Gymnema sylvestre (GS) plant has confirmed results from lab tests that the ingredient can help reduce blood glucose, adding weight to its diabetes benefits. The trial found that supplementation with the GS extract for 60 days resulted in increased levels of insulin and C-peptide, together with lower levels of blood glucose. These latest findings add further support to the potential of the ingredient to address type 2 diabetes.

     Gymnema sylvestre, grown primarily in the Indian sub-continent, has been used India for centuries as a traditional folk remedy to help maintain optimal health. The study also confirms previous findings that GS stimulates insulin secretion similar to sulphonylureas and meglitinide analogues that are currently used for the treatment of type 2 diabetes.

In this small study the average age of participants was 50, and they were all recently diagnosed with type 2 diabetes or had previously received standard drug treatments for the condition.

     All participants received 500mg of GS Extract twice daily, taken before food for a duration of 60 days. There was no control group. Blood samples were taken at the start and end of the trial, and blood glucose, insulin and C-peptide levels were measured.

The researchers from King's College London and Burdwan Medical College, J. B. Ayurveda College and Calcutta University, West Bengal, found that supplementation with GS resulted in “significant improvements” in glycemic control in ten of the 11 participants.

     Their findings recorded an average reduction in fasting blood glucose from 162 ± 23 to 119 ± 17 mg/dL. After eating, blood glucose levels were found to have reduced from 291 ±10 to 236 ±30 mg/dL. The researchers said it was “unclear” why one participant showed no reduction in glucose levels after GS treatment.

     A parallel in vitro test examined the effects of GS on the pattern and rate of insulin secretion using human islets. Supplementation of the cells with 0.125mg/ml GS resulted in a two-fold increase in insulin secretion. The secretion was sustained for the duration of exposure to GS and rapidly reversible upon its withdrawal, said the researchers. The study is published in Phytotherapy Research.