Probably the biggest no1 thing with diabetes is to get exercise if you can, and watch what you eat. It's easy to get lazy. In my younger years, I was hypogycemic. Nowadays I'm leaning the "other way."
Yes, diet and exercise are the best way to postpone/prevent diabetes. My uncle is in a study on this and so far hasn't gotten diabetes yet. It seems to be working for him.
Sometimes it can reverse the diabetes, but not always...
I like to refer to it as Diet-betes.... As you have to watch your diet so closely...
My mom was trying the adkins diet, as it also can help control diabetes, but I don't know all of the details...