I explained it all in the posting, "Food Issues."
But people don't take the time to think and realize the distinction, so I am working on a concise one-liner to help educate. I will make the attempt here, and as time goes on, I will edit and revise my one-liner:
No, not diet controlled. Cured through proper diet; not controlled through prescribed diet.
OR I was thinking about something like: Not diet controlled; pancreas controlled.