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How accurate is HbA1c?

NeetaMD

Active Member
Messages
27
Location
Gloucestershire
Type of diabetes
Prediabetes
Treatment type
Diet only
Dislikes
People being unkind
Hi, I am in the UK and my HbA1c has been in the pre-diabetes range since 2017. However, I only eat within a 10 hour period so my blood sugars rises are only after my 3 eating episodes as I don’t snack. For the remaining 14 hours when I am fasting my blood sugars are usually within the normal range. Does anyone know if this might mean that if I ate like many do, three meals a day plus a couple of snacks spread out over say a 14 or 15 hour period a day my HbA1c could potentially be higher?
 
Hi, I am in the UK and my HbA1c has been in the pre-diabetes range since 2017. However, I only eat within a 10 hour period so my blood sugars rises are only after my 3 eating episodes as I don’t snack. For the remaining 14 hours when I am fasting my blood sugars are usually within the normal range. Does anyone know if this might mean that if I ate like many do, three meals a day plus a couple of snacks spread out over say a 14 or 15 hour period a day my HbA1c could potentially be higher?
Hi there @NeetaMD I’m not sure what you mean by “eating episodes” ? To answer your question in part, my thoughts are, it is probably what you eat and how efficient your body is at metabolizing that food efficiently , notably carbohydrates and sugars, that counts.
Snacking between meals can cause weight gain in some, this may aggravate an already distressed system and may lead to increased blood sugars in those people who are susceptible to type 2 diabetes.

I’m not sure I have answered your question, but I think body metabolism is complex with many factors at play so there is no straight forward answers to your question in my opinion. :)
 
The simple answer is it could, but equally it might not. HBAic is effectively measuring your average blood sugar over 2 to 3 months. So if eating snacks raises your blood sugar significantly, or keeps it raised for a longer time then yes HbA1c will rise. On the other hand if the snack does not raise your blood sugar HbA1c will not rise.

To illustrate that a snack for me of a piece of cheese or handful of walnuts does not raise my blood sugar (it can even make it drop a little).

If I were to eat a bag of crisps or a piece of toast I would see a significant fast rise. If I then did that more than once a day my overall blood sugars would raise and my HbA1c would be higher.
 
Hi, I am in the UK and my HbA1c has been in the pre-diabetes range since 2017. However, I only eat within a 10 hour period so my blood sugars rises are only after my 3 eating episodes as I don’t snack. For the remaining 14 hours when I am fasting my blood sugars are usually within the normal range. Does anyone know if this might mean that if I ate like many do, three meals a day plus a couple of snacks spread out over say a 14 or 15 hour period a day my HbA1c could potentially be higher?
The biggest influence on your BG and therefore the HbA1c result, is the carbohydrate - starches and sugars - that you put in your mouth. Your liver will then do its best to keep you at its idea of what your BG should be - but the liver takes its cue from how high your BGs have been recently.

So it's not only a question of how many times you eat, it's what you eat. If you aren't eating carb, you won't see a BG rise caused by carb. I eat once a day - I really don't want to eat more often (no hunger) because I eat mainly fats and protein.
 
Thank you @Melgar. When I say eating episodes I mean that I don’t graze but have 2 meals and a light evening snack. I don’t eat low carb as I was specifically advised by GP not to restrict these but to focus on complex, low GI carbs instead. However I don’t process those carbs very well with my glucose levels staying higher for longer than expected after eating so I agree it all depends on an individual’s metabolism.
 
Thank you @Lakeslover. I know that if I restricted my carb intake I might lower my HbA1c but I would have to ensure I keep my calories intake up to avoid losing more weight. You sound like you are clear on what you can eat to avoid those harmful blood glucose rises.
 
Thank you @KennyA. How do you manage on one meal a day without losing significant weight? I eat good sized meals and have a great appetite yet can’t put the weight on and my GP believes I am in denial and might actually have an eating disorder!!
 
Thank you @Lakeslover. I know that if I restricted my carb intake I might lower my HbA1c but I would have to ensure I keep my calories intake up to avoid losing more weight. You sound like you are clear on what you can eat to avoid those harmful blood glucose rises.
From my experience I can restrict my carbs but keep calories up by adding things like cheese, butter and cream.
 
From my experience I can restrict my carbs but keep calories up by adding things like cheese, butter and cream.
Thanks, but I’ve already upped my intake of those foods and have each daily. Without the carbs I can’t avoid losing more weight which is why I’ve been advised to avoid restricting them but then can’t lower my HbA1c
 
Thank you @KennyA. How do you manage on one meal a day without losing significant weight? I eat good sized meals and have a great appetite yet can’t put the weight on and my GP believes I am in denial and might actually have an eating disorder!!
The short answer is that I'm not ever hungry. I don't force myself into "one meal a day" - one meal a day is what happens because it suits me. I tend to eat a substantial meal in the early evening, but I might have something - cheese/salami etc - early afternoon. Yesterday's food was cheese/salami rollitos about 3pm, and a chicken curry about 7pm.

So I'm not energy deficient, and although I'm almost always in ketosis because my carb intake is around 20g/day, I'm stable.

I did lose significant (somewhere around 90lbs, about 30% of my starting figure) weight in 2021-23, but I seem to have stabilised at least for the present. It's possible I've lost all the visceral fat I used to have, and maybe some subcutaneous. I've certainly easily regained some muscle, which is not supposed to be that easy at my age.
 
The short answer is that I'm not ever hungry. I don't force myself into "one meal a day" - one meal a day is what happens because it suits me. I tend to eat a substantial meal in the early evening, but I might have something - cheese/salami etc - early afternoon. Yesterday's food was cheese/salami rollitos about 3pm, and a chicken curry about 7pm.

So I'm not energy deficient, and although I'm almost always in ketosis because my carb intake is around 20g/day, I'm stable.

I did lose significant (somewhere around 90lbs, about 30% of my starting figure) weight in 2021-23, but I seem to have stabilised at least for the present. It's possible I've lost all the visceral fat I used to have, and maybe some subcutaneous. I've certainly easily regained some muscle, which is not supposed to be that easy at my age.
Well done! Sounds like you have it sorted.
 
Hi, I am in the UK and my HbA1c has been in the pre-diabetes range since 2017. However, I only eat within a 10 hour period so my blood sugars rises are only after my 3 eating episodes as I don’t snack. For the remaining 14 hours when I am fasting my blood sugars are usually within the normal range. Does anyone know if this might mean that if I ate like many do, three meals a day plus a couple of snacks spread out over say a 14 or 15 hour period a day my HbA1c could potentially be higher?
Hi NeetaMD,
I have often wondered about this myself. I also have been pre diabetic a good while, since 2016 that I know about. I’d managed to keep to pre diabetic levels by watching my carbs and eating and exercising sensibly. I do think if I ate more regular meals and snacks my HBA1C would be higher. I have lots of hours inbetween eating that my glucose is normal then after eating it will be higher than normal. So the overall average keeps me out of diabetes levels. I think you will understand what I mean lol. I’m currently in discussions with my doctor as I think my glucose intolerance was bought in by the medication I was prescribed for 26 years. They recently asked me to stop taking it as they think it could be the cause. I’m upset that it took all these years to say that. Are you on any medication that could cause your glucose problems?
 
Hi NeetaMD,
I have often wondered about this myself. I also have been pre diabetic a good while, since 2016 that I know about. I’d managed to keep to pre diabetic levels by watching my carbs and eating and exercising sensibly. I do think if I ate more regular meals and snacks my HBA1C would be higher. I have lots of hours inbetween eating that my glucose is normal then after eating it will be higher than normal. So the overall average keeps me out of diabetes levels. I think you will understand what I mean lol. I’m currently in discussions with my doctor as I think my glucose intolerance was bought in by the medication I was prescribed for 26 years. They recently asked me to stop taking it as they think it could be the cause. I’m upset that it took all these years to say that. Are you on any medication that could cause your glucose problems?
Hi, worrier1971 your experience certainly sounds similar to mine. I have also taken up running three times a week and my glucose control is definitely improved on those days. I know what you mean about medication. I have genetic, inherited high cholesterol so have been taking statins for a number of years. I know that this increases the risk of having type 2 diabetes but the statins themselves may not be the cause. Some people have a lifestyle that increases their risk of raised cholesterol but some of those lifestyle choices are similar to those that can contribute to type 2 diabetes. I don’t believe that is necessarily true for me and I I have been advised not to stop the statins
 
Thanks, but I’ve already upped my intake of those foods and have each daily. Without the carbs I can’t avoid losing more weight which is why I’ve been advised to avoid restricting them but then can’t lower my HbA1c
May I ask what you typically eat in a day?
 
May I ask what you typically eat in a day?
Typical day

LUNCH - 2 slice granary sourdough sandwich (cheese, egg, tuna or peanut butter) with large salad and a few of my husbands crisps followed by small home baked low sugar cookie or similar and apple.
or
Homemade soup (veg and pulses) and cheese scone with cheese followed by cookie and apple.

DINNER - eg. today - Smoked salmon and roasted vegetables on small portion of whole meal spaghetti with one slice of garlic baguette followed by mixed berries and full fat Greek yoghurt.

SUPPER - 1/2 Banana, few grapes, handful Brazils and plain peanuts. 2 squares dark chocolate

Also double cream in my afternoon coffee
 
Well done! Sounds like you have it sorted.
It's been six years, so far so good. The key thing in my experience is that eating carbs raises your blood glucose. If you don't eat them, no BG rise. Give it a few weeks, and your liver adjusts to the new normal and will actively try to maintain BG at a lower level.
 
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