A1c high but blood glucose low

Maximummick

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I just got my A1c at 46. But for 3 months I’ve been measuring my blood glucose before and 2 hours after meals and it is normal. Under 6 before meals and never higher than 7 or so after, so my average predicted an A1c of about 37. Why is it so high?
 

Tophat1900

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Your glucose levels could be higher between meals, some people get a spike at 3 or 4 hrs post and there is also the overnight period. Or the test could also be affected by other issues relating to Hba1c tests issues.
 

Muneeb

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I just got my A1c at 46. But for 3 months I’ve been measuring my blood glucose before and 2 hours after meals and it is normal. Under 6 before meals and never higher than 7 or so after, so my average predicted an A1c of about 37. Why is it so high?

Unless you have a cgm, you will never know accurately what you BS levels are doing. If you test at 2 hours you may have missed the peak or alternatively may not have reached it. That's the drawback of point measurements from meter.
 

Maximummick

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I understand about missing a spike but I have tested at 30mins, 1 hour and 3 hours after a meal with no spike. My A1c was 49 3 months ago so I embarked on a very low carb diet and load of exercise. A modest reduction to 46 after all that work on my lifestyle is a real blow. How long does it take to make a difference to prediabetes?
 

JoKalsbeek

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I understand about missing a spike but I have tested at 30mins, 1 hour and 3 hours after a meal with no spike. My A1c was 49 3 months ago so I embarked on a very low carb diet and load of exercise. A modest reduction to 46 after all that work on my lifestyle is a real blow. How long does it take to make a difference to prediabetes?
What do your meals look like now? On average? The last blood sugars to come down are the fasting ones in the morning. For me, they're usually the highest I have all day. You could check your fasting blood glucose when you wake, and see whether Dawn Phenomenon is tripping you up. If so.... The low carb should take care of that in time, but it'll take a good while.
 

Muneeb

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I understand about missing a spike but I have tested at 30mins, 1 hour and 3 hours after a meal with no spike. My A1c was 49 3 months ago so I embarked on a very low carb diet and load of exercise. A modest reduction to 46 after all that work on my lifestyle is a real blow. How long does it take to make a difference to prediabetes?

But when you say you don't see spikes of higher than 7; a hba1c of 46 means you have an average glucose level of ~7.5 mmol/L. So at some point it must be much higher than that to balance out the lower readings you also have. It may be you are running higher overnight and not knowing?
 

Maximummick

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What do your meals look like now? On average? The last blood sugars to come down are the fasting ones in the morning. For me, they're usually the highest I have all day. You could check your fasting blood glucose when you wake, and see whether Dawn Phenomenon is tripping you up. If so.... The low carb should take care of that in time, but it'll take a good while.
My morning fasting numbers for the last 3 months are from 4.4-5.9. The highest after a meal was 7.3 but usually they are much lower. I do get spikes after a run up to 7-9 (cortisol?) but then they go right down after 30 minutes. I run 4 time a week. So none of these numbers explain my A1c being 46. I am due to see the diabetes nurse in a couple of weeks so maybe I'll get some answers then. I am worried that she will put me on Metformin and I'll get dangerous hypos or she won't and I'll develop poorly controlled type 2. Maybe I need a cgm?
 

woollygal

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I’m kind of the same. Mostly my sugars are good. Ok I do have the odd spike but 98% of the time they are good.
Yet my hba1c is still well was 57.
Very frustrating
 

JoKalsbeek

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I reversed my Type 2
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My morning fasting numbers for the last 3 months are from 4.4-5.9. The highest after a meal was 7.3 but usually they are much lower. I do get spikes after a run up to 7-9 (cortisol?) but then they go right down after 30 minutes. I run 4 time a week. So none of these numbers explain my A1c being 46. I am due to see the diabetes nurse in a couple of weeks so maybe I'll get some answers then. I am worried that she will put me on Metformin and I'll get dangerous hypos or she won't and I'll develop poorly controlled type 2. Maybe I need a cgm?
That's weird. Though the spikes after running make sense, as it is strenuous. You could just try long walks instead, go for (seriously long) distance rather than speed. That shouldn't cause spikes in any case.
I can put your mind at ease about metformin though: it doesn't cause hypo's. It just tells your liver to dump less glucose, might suppress hunger some. If the height of the HbA1c is to blame on your liver dumps, then that would fix it. (Provided you don't get lasting side effects. If you do go that route, ask for slow release met from the get-go and always take it with food, never on an empty stomach.) It's medication like gliclazide that forces the pancreas to put out more insulin, and that can cause hypo's. Met won't.
 

Tophat1900

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My morning fasting numbers for the last 3 months are from 4.4-5.9. The highest after a meal was 7.3 but usually they are much lower. I do get spikes after a run up to 7-9 (cortisol?) but then they go right down after 30 minutes. I run 4 time a week. So none of these numbers explain my A1c being 46. I am due to see the diabetes nurse in a couple of weeks so maybe I'll get some answers then. I am worried that she will put me on Metformin and I'll get dangerous hypos or she won't and I'll develop poorly controlled type 2. Maybe I need a cgm?

A cgm may well reveal a lot of info about why your A1c is what it is, but getting one is another matter. Just remember, you can't be forced to take something if you don't want to. You are part of the decision making when it comes to your health.
 

Shiba Park

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164
Type of diabetes
Type 1
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Insulin
The 'average' is based on the typical lifespan of red blood cells. I've seen web pages that say this can vary by as much as 30%. Perhaps you have particularly long lived red blood cells?

Shiba.
 

Maximummick

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The 'average' is based on the typical lifespan of red blood cells. I've seen web pages that say this can vary by as much as 30%. Perhaps you have particularly long lived red blood cells?

Shiba.
I wondered about my red cell lifespan. I think I'll get a CGM. I first got an A1c in September 2018 at 46. I completely ignored it as my fasting blood sugars were so good and went sugar crazy until November 2019 when it was 49 and I realised I had a problem. I now have less than 30g of cabs all complex with fibre a day and after 3 months of that it only went down to 46 so I am really confused and upset why it has not moved. I read David Cavan's book and reversing diabetes and followed everything so the result yesterday has left me confused. I am 66, 6ft tall and less than 12 stone. I am fit, I ran a half marathon in September so I am very upset all my good work on my health has failed in this instance. I do not know if I am diabetic, prediabetic or normal.
 

HSSS

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If a libre doesn’t give the missing answers then consider if the hb1ac is faulty for you for some reason. Some blood conditions can effect it.
 

Muneeb

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Type of diabetes
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Does the Libre collect data at night?

It stores the last 8 hours data, so as long as you scan at least every 8 hours you will have all the data. Buy a libre sensor and use your phone to scan, don't even need a reader tbh.
 
M

Member496333

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I have read that whole-food low-carb eating can increase red blood cell lifespan, thereby artificially inflating HbA1c.

I maintain that A1c is both an imperfect measure and a poor indicator of control. Certainly when comparing across populations, and definitely as a diagnostic criteria for type 2.
 

Maximummick

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I just looked at my blood work. I have a low red blood cell count and low haemoglobin. I wonder if that is why my a1c is higher than my blood glucose tests suggest. I will order a cgm and get some data.
 
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JoKalsbeek

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I just looked at my blood work. I have a low red blood cell count and low haemoglobin. I wonder if that is why my a1c is higher than my blood glucose tests suggest. I will order a cgm and get some data.
And there's your answer. Your HbA1c is incorrect.
 

Helen46

Active Member
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28
Just throwing this out there. I have been working really hard to reduce HbA1c!!!! But last week I had nightmare day, Three phone calls to Medtronic over an 8 hour period Sensor seemed to be working but intermittently sensor was suspending pump but as it was a new sensor I was determined to try and "save" it. I did all the recommended things but was getting severely rattled and ultimately fell asleep after midnight after taking the sensor off and believing the problem was with the transmitter.

Woke some six hours later with BG of close to twenty. My fault as I was concentrating on the sensor/transmitter but unfortunately i was scheduled for an HA1c test two days later...HbA1c has gone up! I am thinking that the high readings over what appears to be an 8 hour period had a crucial and disproportionate effect. My ISIGs are usually 26-29 but on this day it was 6! Any thoughts. Feeling fairly dispirited.