Lower bound of normal blood sugar?


What is the lower bound of a normal person’s blood sugar? I was surprised to have a morning fasting number in the 60s today (and I know it could be higher than that “really” due to allowed variations in meters). Since I don’t take exogenous insulin I thought, “well, it must be normal to go that low.” Anybody know?

Most type 2s not on insulin still have a functioning counterregulatory system and when you get below 70 mg/dl or so your body will dump blood sugar to bring you back up. I’ve been able to drive my blood sugar down into the 50s, but I feel hypo and then counterregulate so I don’t stay there very long.

How did you figure that out, just out of curiosity? Did you have a CGM on at some point? I’ve felt totally exhausted and bad and thought that my BG must be high, and then tested and it was in the 80s. I wonder if that’s me going low and then the counterregulatory thing kicking in before I have a chance to see the low number.

Yes, it is normal for non-diabetics to have readings that low. The reason people with diabetes (mostly those on insulin) are given a higher target range is because the difference between a 60 and a 40 isn’t all that far and can happen very fast.

Also, being in the 60s when you get up means you might have been lower (too low) during the night. If that happens regularly, you might need to eat a snack before bed.

If I eat, then do aerobic exercise within a half hour, I can induce a hypo. It is basic reactive hypoglycemia. I get the readings from my meter. Within 15 minutes, my body will just recover on it’s own, usually with a mild high 120-140 mg/dl.

Yeah, the non-d can go to what we would consider low. My mom who doesn’t have D had to fast for blood work and they tested her fasting BG and it was lke 65! At the time, I thought it was too low or I was reading the lab printout wrong because i was a newb with a FBG of 205 but after reading these posts here I see that it is possible. (I was also jealous. hehe)



Funny how all my immediate family is all interested in their BG when I got dx. I guess they were freaked out they would end up like me.

That said, I had a few weeks a few months ago where I was waking up in the low 70s and high 60s sometimes - which stopped but it is possible. I lfelt fine though. Not low.

I’ve tested family members who had fasting in the 60’s. Don’t know how long they remain there.