Hi Ruth,
Can't point to any specific studies at the moment but, from what I understand from reading many message posts and other Diabetes-related info... a balanced and healthy lifestyle goes a long way in reducing, significantly postponing or, in some cases, eliminating the need for medications (Type2).
Since we all vary in so many ways, I think it impossible to really put an ETA on when you can expect the shoe to drop (so to speak), but I do believe that a consistently healthy lifestyle (maintaining good glucose, cholesterol, and blood pressure), can see you well into old age in a much better state than your "average" individual. Just my opinion