I recently did a test with a burrito (about 55g carbs total) and here are the results: before eating 100, 1 hr 165, 2 hr missed, 3 hr 100, 4 hr 79 (tested twice to verify). Why is my glucose going much lower than fasting after eating a high carb meal? Is this a sign of insulin resistance? Maybe this explains why I was always feeling so crappy mid morning and mid afternoon before I started my lowered carb/exercise routine. My latest fasting glucose on this routine was 97 which is an improvement, or maybe just normal variation. Any thoughts? I have been concerned that I am early type 1.5.
People with diabetes can experience dawn phenonmenon (lots of info here about this). Briefly, DP occurs when the liver dumps glycogen in preparation for waking up. Lowest BG naturally tends to be overnight between 2-4 AM. Without insulin to prevent BG from going too high, DP results in high morning numbers, for many the highest of the day. Morning fasting being significantly higher than BG before bed indicates DP (unless you ate a lot close to bedtime).
This could explain your fasting being higher than after a high carb meal, though this isn’t really accurate because you were at 165 1 hour after eating the burrito, though came down to normal later.
If you were physically active during the 4 hours after eating, your BG would go down.
First off, some type 2 and pre-diabetics suffer from reactive hypoglycemia where you eat some carbs, your blood sugar rises, your body dumps insulin, but it dumps too much causing you to go low. Frankly, you response indicates a mildly impaired glucose tolerance. And a 79 mg/dl is actually a normal fasting numbers. With the readings you have provided, you might be pre-diabetic, but you are hardly in “bad” shape. I would kill for your numbers. There is no way you could say anything about type 1.5 since you are still in the fuzzy range between “normal” and pre-diabetic. My recommendation to you is: keep an eye on your diet (think lower carb) and exercise regularly and there is every reason to believe that you could remain normal and prevent diabetes from emerging for quite some time (perhaps ever?). But of couse, I could be wrong, just ask my wife.