some have genetic predisposition to diabetes...i.e. family history: many relatives with diabetes and so on. risks are higher for these people, of course
in any case, limiting sugars is probably the only long-term preventive strategy
try to get more carbs from veg and rice than from glucose-like sugars....
keeping bf leves low would probably also be a good idea
most acquired diabetes come from long-term poor eating habits, so here is the clue.