HbA1C

[Roy Batty]

I've posted previously about being labelled as prediabetes because of my blood sugar level, my most recent test in February 2025 showed it had risen to 46 mmol/mol (6.4%). I'm extremely active and fit, I don't eat UPFs, pastries, pizzas, cakes, cookies, biscuits, pasta, potatoes, candy, sweets. I'm struggling to understand the causes of my high BG levels as it not from diet, lifestyle, stress, lack of sleep or any of the other common factors. My Tryglyceride:HDL-C ratio suggests I do not have insulin resistance. My body fat % is 15, my visceral fat is <90 cm2. My LMI and ALMI are in the 98th centile. My BP is 110/70. I'm on no medication and I have no health issues. I'm 67.

I've been searching for reasons for my high BG and yesterday I listened to a podcast by Drs Ben Bikman and Ken Perry, about how HbA1c alone is not enough and can even give false positives. If I have understood correctly HbA1c measures the glycation of RBC (red blood cells), but the older RBCs are the more likely they are to be glycated. RBC age varies but is around 110-120 days. For some individuals it may be as short as 70 days, for others as long as 140. It seems that RBC age may increase as we ourselves age, so that BG levels are likely to rise over time for this as well as other reasons not related to diet, lifestyle etc i.e it's a function of getting older and normal.

The podcast also discussed a fructosamine test as either an alternative or adjunct to HbA1c as it looks at a different form of glycation. I struggled to understand this and I wonder if any forum members, moderators or admins can simplify what it tests and why it's used please.

 

[Antje77]

The podcast also discussed a fructosamine test as either an alternative or adjunct to HbA1c as it looks at a different form of glycation. I struggled to understand this and I wonder if any forum members, moderators or admins can simplify what it tests and why it's used please.

A fructosamine test is usually used in situations where an hba1c test is unreliable. Certain conditions like aneamia can skew hba1c results.
It is also sometimes used in pregnancy, because gestational diabetes develops over a shorter timespan than T2, the hba1c will be lower than should be expected from average blood glucose.

 

[Roy Batty]

A fructosamine test is usually used in situations where an hba1c test is unreliable. Certain conditions like aneamia can skew hba1c results.
It is also sometimes used in pregnancy, because gestational diabetes develops over a shorter timespan than T2, the hba1c will be lower than should be expected from average glood glucose.

Thanks, if HbA1c is testing for glycated RBCs what is a fructosamine test testing?

 

[KennyA]

Hi - I'd echo what's said above. The text above is from Bilous and Donnelly and it basically confirms that while HbA1c is fine as a diagnostic tool for most people there are a few individuals for whom one of the alternative tests is more appropriate.

edited for typo

 

[KennyA]

Thanks, if HbA1c is testing for glycated RBCs what is a fructosamine test testing?

Again taken from Bilous and Donnelly.

 

[Chris24Main]

Glucose affects things it comes in to contact with.
The more glucose, the more often it will contact things
If you can measure the affected thing, you can estimate the amount of the glucose around for the lifetime of the thing.

Gylcated Heamoglobin A1 is one thing - over a 3 month life
Fructosamine - glycated protein - is another with a shorter lifespan.

As per @KennyA s article - there are a different bunch of potential issues.

Clearly in your case it's the stress of being a replicant and staying under cover all these years...

 

[Chris24Main]

While I'm a big fan of both Ben Bikman and Ken Berry - I don't think I would ever point anyone at either of them as a first introduction to metabolism - they are both pretty hard core, and Ben; in particular - calling his channel the metabolic classroom is no joke - you need to sit down and take notes.

All your other markers are amazing - if you pardon the expression, my gut sense is that you are an athlete (or at least athletic), and not fat adapted, meaning simply that you use a lot of fuel, and most of it has to come from glucose - therefore your liver will provide what you need.

I don't normally do this, and if I'm off the mark, please ignore this all together - you may like this:

https://journals.physiology.org/doi/full/10.1152/ajpcell.00583.2024

It represents the state of the art as it stands right now regarding the interface between sports science and nutrition/ metabolism. You may find some answers there...

More general apologies - reading that again, it's more diagnostic than I intended - we can not and should not offer anything approaching a diagnosis, and I hope it's clear that I'm not trying to do that, only agree that all else but HbA1c looks great... so it's probably more about what you're doing than eating.

 

[Roy Batty]

While I'm a big fan of both Ben Bikman and Ken Berry - I don't think I would ever point anyone at either of them as a first introduction to metabolism - they are both pretty hard core, and Ben; in particular - calling his channel the metabolic classroom is no joke - you need to sit down and take notes.

All your other markers are amazing - if you pardon the expression, my gut sense is that you are an athlete (or at least athletic), and not fat adapted, meaning simply that you use a lot of fuel, and most of it has to come from glucose - therefore your liver will provide what you need.

I don't normally do this, and if I'm off the mark, please ignore this all together - you may like this:

https://journals.physiology.org/doi/full/10.1152/ajpcell.00583.2024

It represents the state of the art as it stands right now regarding the interface between sports science and nutrition/ metabolism. You may find some answers there...

More general apologies - reading that again, it's more diagnostic than I intended - we can not and should not offer anything approaching a diagnosis, and I hope it's clear that I'm not trying to do that, only agree that all else but HbA1c looks great... so it's probably more about what you're doing than eating.

Thanks, I'll take a look at that. I'm not sure though what you mean by what I'm doing more than eating. Can you clarify this for me please?

 

[Chris24Main]

Sure - and I don't mean that to be in any way contentious - we all do more than eat.

If (and I'm still assuming ..) you are doing a lot of exercise, and your metabolism is based around glucose (like almost everyone is) then you will be regularly depleting the stores of glycogen (stored glucose) in your muscles and liver.

Your liver will be therefore making more in order to keep up with what is "normal" for you, ie, there is an expectation of needing a lot of glucose to be able to burn it for energy.

I may be failing to explain - your liver is a powerhouse for turning stuff into other stuff, it's perfectly capable of providing all the glucose you need, regardless of whether you eat any carbs or not - so it will simply maintain a "normal level" - if you think that it's only about what you eat, (and this is really what we're told to think, so ...) then it's likely to be a bit confusing.

 

[Melgar]

I've posted previously about being labelled as prediabetes because of my blood sugar level, my most recent test in February 2025 showed it had risen to 46 mmol/mol (6.4%). I'm extremely active and fit, I don't eat UPFs, pastries, pizzas, cakes, cookies, biscuits, pasta, potatoes, candy, sweets. I'm struggling to understand the causes of my high BG levels as it not from diet, lifestyle, stress, lack of sleep or any of the other common factors. My Tryglyceride:HDL-C ratio suggests I do not have insulin resistance. My body fat % is 15, my visceral fat is <90 cm2. My LMI and ALMI are in the 98th centile. My BP is 110/70. I'm on no medication and I have no health issues. I'm 67.

I've been searching for reasons for my high BG and yesterday I listened to a podcast by Drs Ben Bikman and Ken Perry, about how HbA1c alone is not enough and can even give false positives. If I have understood correctly HbA1c measures the glycation of RBC (red blood cells), but the older RBCs are the more likely they are to be glycated. RBC age varies but is around 110-120 days. For some individuals it may be as short as 70 days, for others as long as 140. It seems that RBC age may increase as we ourselves age, so that BG levels are likely to rise over time for this as well as other reasons not related to diet, lifestyle etc i.e it's a function of getting older and normal.

The podcast also discussed a fructosamine test as either an alternative or adjunct to HbA1c as it looks at a different form of glycation. I struggled to understand this and I wonder if any forum members, moderators or admins can simplify what it tests and why it's used please.

@Roy Batty, Lean, very fit individuals with raised blood sugars is definitely a thing. You will find a few members on the forum with in a similar situation. Like me they have tried the very low carb diet, with little success. I tried it first 9 months with very little movement in my blood sugars. I was a competitive athlete up until around 10 years ago and I still exercise. I do the equivalent of three marathons a week. I do fast walking which to be honest may as well be a slow jog. My BMI is around 19. Low triglycerides. As a matter if interest do you produce low levels of ketones all the time? My Dr stated that it is clear that my muscles are insulin sensitive and that bears out with low normal C-Peptides which I paid for.
Im not on a very low carb diet, but I do watch my carbs and I am very careful what I eat. An issue I have is if I reduce my carbs I lose weight, like it drops off me. My pants literally drop off from the weight loss, it is so significant. So I have to eat more carbs. It was the same on the very low diet, but even worse.

For sure check out the fructosamine test, that may give you a lower reading, but bear in mind for some people the ‘classic T2 loosing a few pounds and going on a very low carb diets brings their blood sugars right down. For others, particularly the fit lean types these lifestyle changes do nothing. I have managed to get my blood sugars into the normal range 5.8% but I’m on meds and I do a hell of a lot of exercise.
edit spelling

 

[Roy Batty]

Sure - and I don't mean that to be in any way contentious - we all do more than eat.

If (and I'm still assuming ..) you are doing a lot of exercise, and your metabolism is based around glucose (like almost everyone is) then you will be regularly depleting the stores of glycogen (stored glucose) in your muscles and liver.

Your liver will be therefore making more in order to keep up with what is "normal" for you, ie, there is an expectation of needing a lot of glucose to be able to burn it for energy.

I may be failing to explain - your liver is a powerhouse for turning stuff into other stuff, it's perfectly capable of providing all the glucose you need, regardless of whether you eat any carbs or not - so it will simply maintain a "normal level" - if you think that it's only about what you eat, (and this is really what we're told to think, so ...) then it's likely to be a bit confusing.

Your post wasn't at all contentious in my eyes. Your hypothesis that the liver is making more glucose in readiness is interesting and I can make the evidence fit, always useful. I've gone hard with an increase in exercise since the beginning of the year by doubling the number of reps of the resistance exercises I do, body weight, resistance bands and free weights. I've also upped my daily protein intake to about 1.5 grams per Kg, that's about 150 grams for me.

 

[Flane]

Hi, I am interested in this thread as I am also a slim, fit 59-year-old with a high hba1c (45)with no obvious causes. I am trying to eat low carb, but also struggle as the weight drops off when I don’t eat enough - I just can’t seem to eat enough without at least a LITTLE porridge, oatcakes, sweet potato, brown rice. My cholesterol ratios and BP are in the normal range. The hba1c was first tested 6 months ago, so I have no idea how long before that the level has been elevated. I really would love to know if it is a problem!

 

[lovinglife]

Hi, I am interested in this thread as I am also a slim, fit 59-year-old with a high hba1c (45)with no obvious causes. I am trying to eat low carb, but also struggle as the weight drops off when I don’t eat enough - I just can’t seem to eat enough without at least a LITTLE porridge, oatcakes, sweet potato, brown rice. My cholesterol ratios and BP are in the normal range. The hba1c was first tested 6 months ago, so I have no idea how long before that the level has been elevated. I really would love to know if it is a problem!

Your A1c is in the pre diabetic range, so yes slightly high but not too far to go down to none diabetic levels of less than 42 - ideally a little lower.

Do you finger prick test before and after meals to see how the carbs you are eating are affecting your BG? That’s the only way to know really what’s happening. It may be that you can still eat some small amount of certain carbs but without testing you are running completely blind.

If you are eating low carb then can up your fats to satisfy your hunger or to help with the weight loss problem. When we cut the carbs we need to replace it with something, either fats or protein.

The best advice I can give is get yourself a meter if you don’t already have one, you will probably have to self fund as most T2 do.

Testing at first bite and 2 hrs after first bite, you’re looking for a rise of no more than 2, ideally less, if that happens then that means your body has coped with what you’ve eaten. If it’s more you may need to reduce or drop the carbs in that meal.

It’s mooted that it’s also best to be under 7.8 at the 2 hr test, I prefer to be no more than in the mid 6s and 5 or below before my meal.

I’ve tagged one of our members @Rachox for you who has some info on affordable meters if you want to get yourself one

 

[Roy Batty]

Hi, I am interested in this thread as I am also a slim, fit 59-year-old with a high hba1c (45)with no obvious causes. I am trying to eat low carb, but also struggle as the weight drops off when I don’t eat enough - I just can’t seem to eat enough without at least a LITTLE porridge, oatcakes, sweet potato, brown rice. My cholesterol ratios and BP are in the normal range. The hba1c was first tested 6 months ago, so I have no idea how long before that the level has been elevated. I really would love to know if it is a problem!

I wonder if you know your body composition and distribution, especially total body fat and visceral fat. It seems there are some who appear slim, but have a disproportionate amount of visceral fat and this can contribute to insulin resistance. Are you cardio fit, or do you do resistance exercise as well?

I'm relatively new to this myself and also struggling to understand. Unfortunately, there doesn't seem to be a definitive answer, just lots of suppositions, ifs and maybes.

 

[Rachox]

Hi @Roy Batty , thanks for the tag @lovinglife , here’s some info with links for UK meters, and to be clear I have no commercial connections with any of the companies mentioned.



HOME HEALTH have the Gluco Navii, which is a fairly new model and seems to be getting good reviews.

https://homehealth-uk.com/all-produ...ose-meter-test-strips-choose-mmol-l-or-mg-dl/



Links to the strips for future orders:

https://homehealth-uk.com/all-products/glucose-navii-blood-glucose-test-strips-50-strip-pack/



Then they sell the older SD Code Free, details to be found here!

https://homehealth-uk.com/all-products/codefree-blood-glucose-monitoring-system-mmoll-or-mgdl/





SPIRIT HEALTHCARE have a meter called the Tee2 + which is quite popular:

https://shop.spirit-health.co.uk/co...e2-blood-glucose-meter?variant=19264017268793



The strips are to be found here:

https://shop.spirit-health.co.uk/co...py-of-tee2-test-strips?variant=19264017367097



If there is a choice of units of measurement then ‘mmol/L’ are the standard units in the UK, ‘mg/dl’ in the US, other countries may vary.



Don’t forget to check the box if you have diabetes so you can buy VAT free. (for all meters and strips)



If you’d like to try a free 15 day trial of the Freestyle LIBRE 2 plus follow this link:

Sampling | Diabetes Care | Abbott



Dexcom also offer a free trial of their Dexcom one + here

The Dexcom ONE+ CGM (Continuous Glucose Montoring) system | Dexcom

 

[Roy Batty]

Hi @Roy Batty , thanks for the tag @lovinglife , here’s some info with links for UK meters, and to be clear I have no commercial connections with any of the companies mentioned.



HOME HEALTH have the Gluco Navii, which is a fairly new model and seems to be getting good reviews.

https://homehealth-uk.com/all-produ...ose-meter-test-strips-choose-mmol-l-or-mg-dl/



Links to the strips for future orders:

https://homehealth-uk.com/all-products/glucose-navii-blood-glucose-test-strips-50-strip-pack/



Then they sell the older SD Code Free, details to be found here!

https://homehealth-uk.com/all-products/codefree-blood-glucose-monitoring-system-mmoll-or-mgdl/





SPIRIT HEALTHCARE have a meter called the Tee2 + which is quite popular:

https://shop.spirit-health.co.uk/co...e2-blood-glucose-meter?variant=19264017268793



The strips are to be found here:

https://shop.spirit-health.co.uk/co...py-of-tee2-test-strips?variant=19264017367097



If there is a choice of units of measurement then ‘mmol/L’ are the standard units in the UK, ‘mg/dl’ in the US, other countries may vary.



Don’t forget to check the box if you have diabetes so you can buy VAT free. (for all meters and strips)



If you’d like to try a free 15 day trial of the Freestyle LIBRE 2 plus follow this link:

Sampling | Diabetes Care | Abbott



Dexcom also offer a free trial of their Dexcom one + here

The Dexcom ONE+ CGM (Continuous Glucose Montoring) system | Dexcom

Thanks, but I don't need any BG testing kits, I've used them before and I know that my level after 2 hours is raised by <2 and falls again. I don't get any big or prolonged spikes. I don't think there's any value in me testing again with strips and collecting data.

 

[Flane]

Your A1c is in the pre diabetic range, so yes slightly high but not too far to go down to none diabetic levels of less than 42 - ideally a little lower.

Do you finger prick test before and after meals to see how the carbs you are eating are affecting your BG? That’s the only way to know really what’s happening. It may be that you can still eat some small amount of certain carbs but without testing you are running completely blind.

If you are eating low carb then can up your fats to satisfy your hunger or to help with the weight loss problem. When we cut the carbs we need to replace it with something, either fats or protein.

The best advice I can give is get yourself a meter if you don’t already have one, you will probably have to self fund as most T2 do.

Testing at first bite and 2 hrs after first bite, you’re looking for a rise of no more than 2, ideally less, if that happens then that means your body has coped with what you’ve eaten. If it’s more you may need to reduce or drop the carbs in that meal.

It’s mooted that it’s also best to be under 7.8 at the 2 hr test, I prefer to be no more than in the mid 6s and 5 or below before my meal.

I’ve tagged one of our members @Rachox for you who has some info on affordable meters if you want to get yourself one

Thank you! I am a bit squeamish about fingerprick testing, but I know I should probably give it a go.

 

[Rachox]

Hi @Roy Batty , thanks for the tag @lovinglife , here’s some info with links for UK meters, and to be clear I have no commercial connections with any of the companies mentioned.



HOME HEALTH have the Gluco Navii, which is a fairly new model and seems to be getting good reviews.

https://homehealth-uk.com/all-produ...ose-meter-test-strips-choose-mmol-l-or-mg-dl/



Links to the strips for future orders:

https://homehealth-uk.com/all-products/glucose-navii-blood-glucose-test-strips-50-strip-pack/



Then they sell the older SD Code Free, details to be found here!

https://homehealth-uk.com/all-products/codefree-blood-glucose-monitoring-system-mmoll-or-mgdl/





SPIRIT HEALTHCARE have a meter called the Tee2 + which is quite popular:

https://shop.spirit-health.co.uk/co...e2-blood-glucose-meter?variant=19264017268793



The strips are to be found here:

https://shop.spirit-health.co.uk/co...py-of-tee2-test-strips?variant=19264017367097



If there is a choice of units of measurement then ‘mmol/L’ are the standard units in the UK, ‘mg/dl’ in the US, other countries may vary.



Don’t forget to check the box if you have diabetes so you can buy VAT free. (for all meters and strips)



If you’d like to try a free 15 day trial of the Freestyle LIBRE 2 plus follow this link:

Sampling | Diabetes Care | Abbott



Dexcom also offer a free trial of their Dexcom one + here

The Dexcom ONE+ CGM (Continuous Glucose Montoring) system | Dexcom

Thanks, but I don't need any BG testing kits, I've used them before and I know that my level after 2 hours is raised by <2 and falls again. I don't get any big or prolonged spikes. I don't think there's any value in me testing again with strips and collecting data.

Sorry this was for @Flane

 

[Flane]

I wonder if you know your body composition and distribution, especially total body fat and visceral fat. It seems there are some who appear slim, but have a disproportionate amount of visceral fat and this can contribute to insulin resistance. Are you cardio fit, or do you do resistance exercise as well?

I'm relatively new to this myself and also struggling to understand. Unfortunately, there doesn't seem to be a definitive answer, just lots of suppositions, ifs and maybes.

I dont know my body composition but my BMI is <20 and I walk regularly, do Pilates and golf, and don't have any obvious fat. Perhaps that is the problem....

 

[Flane]

Sorry this was for @Flane

Thanks Rachel, I appreciate this information. As a pre-diabetic, I assume I cannot have a free trial?