Do some fish have diabeties?

just wait, i will ask some...............no

Only the sick ones.

No. They don't eat added fructose. Do you know what diabetes is? If you're young and your Isles of Langerhan aren't working you got child hood diabetes. Older and you are taking in more simple sugar than your body can process. A snickers bar and a nectarine have about the same calories. Your body doesn't know that one is supposed to be better for you. It just knows that the nectarine which will put the same pound on your butt if you've hit your caloric intake is harder to convert to glycogen than the snickers. Your brain can only use glycogen. The simpler you make it for your cells, the easier they make it for you. Problem is that simple is bad and harder is good so simple sugar is bad, but complex sugar is OK. Take a blood test any time and if your glucose is above a hundred that is the sugar in your blood. Fast for twelve hours and go above a hundred and you're diabetic.