Hmm. Well, in my humble opinion: I already know I can't eat carbs because my blood sugar will sky rocket but I can control my blood sugar with diet and exercise. At this point, an OGTT would be superfluous for me as it would only confirm what the doctor and I already know. Maybe that's what he means. If it's already confirmed that you are either diabetic or borderline, then he may feel an OGTT isn't needed because he knows what the outcome would be, although of course different people would have different results. I might get much higher readings than you but you might still tip the scales and be diagnosed as "diabetic", too. In any case, I believe the daily monitoring is more important because that shows you and him how your blood sugar is being controlled or not being controlled. And the A1c gives an average for about
3 months. That doesn't account for frequent lows or spikes, though. I believe for first diagnosing diabetes in an unknown patient, then maybe the OGTT is a good tool but once we know the patient is diabetic, then this test might not be needed. (I'm guessing because it seems logical to me.