Just from reading different articles, there's really no "right answer" for the food. I don't know if you've seen this article but it seems to have a lot of good info.
Canine Diabetes: Symptoms, Diagnosis, Treatment, and Diet - Whole Dog Journal Article
I think food does have a lot to do with managing diabetes. I hope you find the right combo. If it's not too much trouble, I'd like to hear about any updates/changes Colleen has with different food.
