Edgar,
Welcome to HealingWell. I found some stuff from The National Institute of Health that indicates it is helpful but not entirely documented in what it can and can't do in humans.
Gymnema sylvestre The information about
regenerating beta cells can be traced to a couple of studies by some doctors from India in 1981 and a follow-up study in 1990. (Shanmugasundaram ERB, Leela Gopinath K, Radha Shanmugasundaram K, Rajendran VM. Possible regeneration of the islets of Langerhans in streptozotocin diabetic rats given Gymnema sylvestre leaf extracts. J Ethnopharmacol 1990;30:265-79) All of the information I can find about
it since then refers back to those two studies. There has been some in vitro work done on rat's pancreatic cells but the results were only applicable to non-insulin dependent type 2's. Anything else that you find online about
this study is posted, sometimes very craftily, by herbal supplement companies, often in the guise of a scientific website.
I firmly believe that if there were a way that Sylvestre was able to regenerate beta cells in humans it would have been followed up by the Juvenile Diabetes Foundation who are very dedicated to finding a cure for this disease. I don't know who told you about
this study but I would go back and ask them for their source so you can do the research yourself. I would be willing to bet that their source is someone selling herbals. (Just my opinion!)