[luncheonmeat]

 Preventable lifestyle disease ...guess he enjoy good life until never exercise.

???

Dis iz like saying cancers are preventable when those living beri healthy lifestyles still can tio.

1) We dunno what type [1 or 2] of diabetes he had.
2) Some folks have a genetic predisposition for diabetes [runs in the family and is not necessarily due to unhealthy lifestyle. As the body runs down with age the cells start to degenerate] . 
3) Serious diabetes will lead to kidney disorder.