This experiment was done on a type 2 diabetes patient. Type 2 diabetes is characterized by damaged islet cells due to a diet high in glucose / carbohydrates. Changing the diet won’t undo the damage, it will just not cause further damage. This patient had enteric neuronal stem cells (nerve tissue from the gut) extracted, and those extracted cells were induced to differentiate into pancreatic islet cells in vitro (in a lab). Once differentiated, they were transplanted back into the patient, and they were able to successfully implant into his pancreas and repair some of the damage his diet had caused.

If the patient had type 1 diabetes, this would not be an effective therapy, as the issue in type 1 diabetes is that the body’s own immune system attacks the cells. A similar approach has been tested for type 1 diabetes, and it has seen some success when combined with immune suppressant drugs to limit the damage caused by the autoimmune disorder.

Since this patient had type 2, however, theoretically he should not need additional therapy as long as he does not go back to a destructive diet or suffer trauma to his pancreas due to accidents.