Question about a1c


Today at the endo office my a1c was 5.8
She was thrilled.
I was meh… but ok with it.
It’s been in the 5’s for about a year.
My question is:
If I am catching my highs and lows within hours if not less than an hour why is my A1c sorta high ( my perspective ) ?
If that is measuring my red blood cells that are glycated then it doesn’t seem to take much to glycate!
Is this a correct assessment on my part?
Thanks All!
FYI I test my insulin numbers with finger pricks and deliver my insulin via syringes.
No cgm or pump in my future.


Your blood glucose (BG) when sleeping plays a large role in the resulting A1c. Do you check your glucose when you first wake up? If so, what is your average wake up number? Have you checked your glucose in the middle of the night, say at 3 am? These two checks could give you a rough idea as to your overnight glucose experience.

How often do you do a finger-stick check? If you’re not aware of a higher glucose level, you’ll not likely take any corrective action. Checking your BG at mealtime and then about 90-120 minutes later will inform you about how well you calculated your meal insulin dose.

Do you pre-bolus? Many people don’t and that will drive post-meal BGs higher than if you use a pre-bolus. I pre-bolus anywhere from 15 to 45 minutes and then keep an eye on my continuous glucose monitor. I know you said you don’t use one but it’s handy for managing situations like you describe.

Having said that, I know from experience that other factors can skew your A1c to over- or under-represent your average glucose. I found out in the last few months that I have iron deficiency anemia. One study showed how diabetics with relatively well-managed glucose and anemia will often leave them with an A1c that is about 0.5% above where it would otherwise be.

By the way, I think an A1c of 5.8% is great!


Thank you!
Oh I pre-bolus and also post bolus for protein.
I am a big tester. When I get up and about twice early am hours.
I have dawn phenomenon and feet on the floor.
Most often I wake to 105-106… yep that predictable.
You struck a note tho that I forgot about and that is slight anemia.
That information you mentioned could very certainly be a player.

So running high for even two hours every day will affect your ac1?

I do catch the highs and the range is 135- 158.
I test pretty much 10 times within a day.

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So a 5.8% A1C is the rough equivalent of a blood glucose level of 120 mg/dl (6.7 mmol).

A1C Conversion Table

To me, the challenge is effectively managing pre-bolusing and accurately matching the delivery of insulin with the arrival of glucose in the bloodstream, along with all the other variables that affect my BG levels (stress, exercise, sleep, moon phase, etc).

Recently, I have been waking up @ 95 - 107 (5.2 - 5.9), BUT I have also been correcting @ 3AM for BGs from 135 - 175 (7.4 - 9.7), ugh!

I guess what I’m meandering to is regardless of how well I do 2 -3 hours post-prandial or with my fasting test, there’s always a significant amount of time when I am trending up after eating or trending down post-prandial and that amount of time is what gets my A1C in the high 5s to low 6s. (And I am happy with that …)


First - congratulations on a 5.8 A1c! That’s not easy to achieve. I know many people who would love that result.

A1c is a number used to represent control over the previous 6 months, but its skewed toward the more recent periods. A1c hemoglobin is eliminated from your system over time- the oldest first. If you had a recent period of less than optimal control it will have a bigger impact on your results.




Point well taken.
Thank you.


That exactly matches my experience. Last A1c was 5.8, 1st time i’ve broken the 6 boundary ever in 36 yrs, which I’m thrilled about, but I was just thinking about this yesterday, watching my CGM trending up about 2hrs after lunch, and realizing that I don’t think there IS any magic formula that will prevent it doing that if I’m eating any significant carbs. I had prebolused, watched for the “bend,” all the right stuff, but it’s just going to do that. Hard thing is resisting the urge to administer a further dose when I see those up arrows. Actually if I’ve had carbs with significant fat involved, I actually do give myself a couple more units at that point, because otherwise it really wants to get up near or over 200, which I hate. Every once in a very long while I’ll see it blip up and then level off at 140-160, but it’s a rare occasion when I get it exactly right like that without it turning out that I’ve overdone it and have to deal with a low an hour or two later on.
—True T1 Confessions


Not all A1c tests done at one’s usual lab will always be as accurate as some of the others. I’ve been using the same lab for about a decade and for the last 4 years, every 90 days. Despite the results being expected, and repeatable similar, I got an outlier of 5.4 about 4 months ago. I figured it was likely wrong (given my CGM and meter data) and sure enough, the recent A1c was in line with my CGM AND more importantly my usual A1c right around 6.0 and 6.1.

IMO, it’s not a good idea to use different labs if you want more consistent lab results.

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In my case, my health insurance dictated my lab choice to one of the big lab chains and since they are continually looking for ways to cut costs, I don’t have a warm and fuzzy feeling that the methods used today are the same as in the past.

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That’s a bummer! Bummer like when I had an HMO for 1 year, a LONG time ago. I hated how I was not able to go anywhere I wanted. Constraints on which lab, doctor, hospital was not something I could embrace. We switched the next year and have never looked back at HMO’s. Oh, and I also had Kaiser for 1 year. THAT was one of THE worst experiences with the birth of my son, and their care of ME for several issues. Yet some people love Kaiser. My experience was dismal.


Actually, if you plan your meal(s), I found one trick to eat large carb meals that can still keep my curve from spiking.
Plan an after meal snack. But bolus for it before eating the main meal.
This is the opposite of doing extended boluses, but by giving a larger than needed bolus for the initial meal, it will affect how your body reacts to the insulin. I know my lines are a lot smoother if I do it this way.
And after a little bit of experimenting, you will know what kind of after meal snack.
I personally like having a fatty snack like nuts, or a protein bar, will give me the best results to control the downward drop after the meal when there is still too much insulin in my system for hte original meal.


Are you on a pump? This is the “superbolus” technique, except instead of having a snack later you can just turn your basal off for an hour or two after eating.


No pump.
No cgm.
No future of either…


I eat low carb…and if I start with nuts it doesn’t end til they are all gone.
So I need to skip this strategy but happy you found one!


I used to have this same problem but found a solution as I buy my Almonds, Walnuts etc in multi lb bags and oftentimes only have large all you can eat buffet option for food. Bought from Amazon small 1/4 cup pinch bowls. I cup worth is about 200 calories and 4-6 grams Carbo depending on nut. These cups are soft rubber and I travel with a few all over the world as they take very little space and then fill 1 cup at buffet line or 1 cup from Almond/Walnut bag and then reseal bag and put it away. Had no nut eating discipline before going this route but can enjoy the full bowl and it is large enough that there is not enough temptation to go back for more.


Oh, I was responding to the person above me. With an A1C of 5.8, who needs the hassle of technology!


Me. I wouldn’t have an A1c of around 6.0 without a pump and CGM. I’m safer now that I have a CGM.

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No, this is more than a superbolus.
For a superbolus, you are only giving the extra amount that is basically equal the amount of basal you would get for the estimated time frame. (Btw, this is SUPER EASY with the Basal-IQ on the X2. Don’t turn the basal off or adjust AT ALL, it takes care of it - for me anyways.)
I take the idea of a superbolus, then add in another set amount of carbs, like a 15 to 20 carb snack. I bolus for that up front, but don’t eat it until after the meal time peak is coming down. And instead of dropping like a rock, the after meal snack levels it out.

The extra insulin up front makes a big difference when eating large/heavy carb meals. Well, for me at least.

Btw, this also works when you have to take a WILD guess at what you are eating when out on the town. Over dose, and plan for a snack…


Um, just gonna put this out there…a consistant A1C in the 5’s without excessive lows for a T1 is not high. At all. No where near high. And if youre thinking 135- 158 is high, well…

I guess Ill keep the rest of my comments to myself.