My 7 year old male cat was diagnosed with diabetes almost 2 years ago. I had been away for a month and noticed changes in his fur (dull and shedding). lower weight and energy level. I am sure I saw it happening before my trip but it was slow so I did not notice it as much as after not seeing him for a month.
The vet said his glucose level was 500+ when I took him in for tests. WOW!!!! Since I travel a lot I was afraid that insulin was not an option since I was not sure my house sitter would handle it. SO I told the vet, I will do everything I can through diet.
I immediately switched to a low/NO carb diet. A mix of Tikicat and Wellness Core. Within days, and I mean days, I noticed a change in Bernie!!!! Within a month his glucose level was almost normal (a bit high but within range) and Bernie's fur never looked so good. That was 2 years ago. I know that diet alone might not work for some cats but I felt like that was the safest chance I had with my work schedule.
Bernie is doing fine. He is back to a healthy weight, is his spunky curious self, and has a shiny coat. confused_cat