Recycling a comment I made on a mailing list in response to someone posting this article about a possible new treatment for type 2 diabetes. Disclaimer: I'm one of those dangerous people who has had little formal science/medicine education but thinks zie knows a lot about it, and these thoughts are worth about what you paid for them.http://news.harvard.edu/gazette/story/2013/04/potential-diabetes-breakthrough/
Researchers at the Harvard Stem Cell Institute (HSCI) have discovered a hormone that holds promise for a dramatically more effective treatment of type 2 diabetes...The hormone, called betatrophin, causes mice to produce insulin-secreting pancreatic beta cells at up to 30 times the normal rate. The new beta cells only produce insulin when called for by the body.
Anything you see that says "we've discovered a hormone that does X in mice" is going to be 10-20 years out from becoming a human treatment. Clinical trials take a lo-o-ong time. And personally I wait another 5 years after a drug is approved before taking it. Many drugs that are approved turn out to cause more harm than benefit (Avandia, I'm looking at you).
When reading scientific articles, it's important to be able to tell which statements are coming from the scientists and which are coming from the journalist writing up the article. In the case of the article you linked, the paragraph about how type 2 is "caused by excess weight and lack of exercise" is written by the journalist, who clearly doesn't know diddly squat about type 2. He or she probably didn't get that information from the scientists, because once a scientist is deep in trying to figure out how to supercharge beta cells, they don't care any more about what causes diabetes.
I took a free online course about diabetes from UCSF last fall. One of the lecturers said that the genes associated with type 2 diabetes affect how many beta cells the pancreas has and how well they function. In other words, people who get type 2 have functioning beta cells, but they might have fewer or less efficient beta cells. And once you have type 2, your insulin production tends to go down over time, so either the existing cells stop working as well, or some of the cells die. (But not everyone has to go on insulin. Many people can manage the condition using diabetes meds their whole lives, because the cells don't stop working altogether.)
This lecturer also said that the number of beta cells a person has decreases if the body is is starved or under stress. A possibility I hear between the lines of that statement: Low calorie dieting, which is essentially starvation, could cause diabetes by reducing the number of beta cells!
At UCSF, there is research into getting stem cells to turn into functioning beta cells. They have actually made this happen, but the beta cells they made aren't as good at figuring out when they need to release insulin as the natural ones.