I don't limit my carbs (I eat over 300 per day and often many more). I've got hypoglycemia unawareness, and have for over a year. My c-peptide is negative. I'm not pumping. I don't have a CGMS. I've averaged different numbers of blood sugar tests per day in different months, from about 5 to 11, but mostly around 7. I'm active, but not really an athlete. I don't have a fixed schedule (which my endo is always saying I should). So sometimes I wonder howcome I've had A1cs below 6.5 for over a year.
Here are a few factors I think matter and get overlooked:
1. Speed of digestion. I digest my food pretty slowly and I rarely get dramatic after meal spikes. That's not to say that my numbers four hours after eating are in range more than half to two third of the time; they're just not any lower than the one hour or two hour mark would be. My blood sugar does not spike if I inject before eating unless I eat a really big meal. Often the Novolog kicks in before the carbs do and I have to inject after or into my meal if I start out with a lowish blood sugar.
2. Computation skills and memory. I remember what my blood sugar was doing in the recent past, and I make judgments based on that. I carb count and compute doses.
3. Riding the trends. I'm open to changing my doses daily depending on the previous day or two days' numbers. Not changing your Lantus for three days to see the full effect is ■■■■■■■■.
4. Patience. I don't retest a hypo for a half hour after the first reading (and sometimes I don't bother retesting at all), and I don't stack insulin.
5. Willingness to risk hypoglycemia.