Thank you! The diabetes link on the page did not work, but I will see what info I can glean from that site and continue to search for more diabetes info. In just a quick glance at the site so far, I already have one idea I will follow up.
It seems that wet food may be better for digestion. I have usually given him dry food, which has been great for his teeth, I must say. Maybe I will incorporate more wet food. He likes to chew on/play with carrots, so maybe something crunchy like that can keep his teeth looking nice.