From what I’ve seen, I believe that cinnamon is helpful with type 2 diabetes. The evidence is simply because there is no monetary value in testing it; most of the drug testing that is done has a financial incentive to the drug companies, and cinnamon offers none.

However, there are side effects to eating too much cinnamon, even ceylon cinnamon; that would be something to discuss with your endocrinologist. It can also effect medications that you may be taking.