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Raised Hba1c on low carb diet

C

CW84

Newbie
Messages
4
Type of diabetes
Prediabetes
Treatment type
Diet only
I started a keto lifestyle 3 years ago, initially to lose weight but kept it up as I experienced such drastic health benefits. So many niggling problems I had experienced for years, disappeared.
I do not know what my hba1c was before I started, as it hadn't been tested, but I think I must have been prediabetic, if not diabetic. However, seven months of eating 20g net carbs a day my hba1c was 5.1%. After a year or so I became a little less strict and would eat around 30g a day. Hba1c remained at 5.1%. After 2 years, I experimented and tried restricting carbs to a near carnivore diet for a couple of months. My hba1c remained at 5.1%. although 5.1% is perfectly fine, it seems strange that even on a diet of virtually no carbs, it could still be a fair bit lower.
Here is the main part of my question:
About 8 months ago I started running and going to the gym 5 days a week. As I had been pretty strict keto for so long and was now adding in exercise, I thought my body must be healthy enough to be slightly more liberal with carbs. I added in about 15-20g extra most days in the form of berries, nuts and extra servings of veggies. My hba1c shot up to 5.7%, which is classed as prediabetic.
How is it possible that I can be prediabetic on 50g carbs a day, whilst also getting a good amount of exercise?
 
Hi @CW84 and welcome to the forum.

Did you think exercise made a difference? Muscle building exercise makes a small diference, but cardio exercise makes less. The harder you exercise, the more glucose you body needs (unless you are using Ketones for energy) and even your liver will make some and kindly add it into your blood stream if you do hard exercise.

We can't outrun a poor diet. The key is in keeping the carbs we eat down low enough.

I know that some people do claim to be cured of T2D, but most of us in remission with 'normal HbA1C levels realise that if we go back to eating like we used to do, we will soon be fully T2D again!
 
50grams of carbs can put you out of keto. Some people can eat more and stay in keto others need to eat less to stay in keto. Maybe try some more healthy fats like avocado to see if that helps
 
As I said, my hba1c has gone up from 5.1% to 5.7% since I started exercising, so the only difference I am seeing in blood sugar isn't good.

I am not trying to put run a poor diet. As I said in my post, my diet is low carb. At under 50g carbs a day, it is considered keto.
 
Most people can stay in Ketosis at up to about 75g a day, BUT many can come out of Ketosis when they go over 20g, we are all different and have to find our own limits. It looks like yours is somewhere between 30 and 45 a day.
 
Under 50gms is considered Keto by whom? It certainly isn't keto for my body. But if I go under 20gms, then I'm probably in Keto.
I 've always called my 20gms to 40gms of carbs per day 'flirting with Keto', but for you it may be different - have you actually verified that you are in Keto at under 50gms ?

However, yes under 130gms is considered Low Carb. But there isn't a one size fits all - our reactions to carbs are unique to our body.

Edited for spelling and punctuation
 
ajbod said:
Most people can stay in Ketosis at up to about 75g a day, BUT many can come out of Ketosis when they go over 20g, we are all different and have to find our own limits. It looks like yours is somewhere between 30 and 45 a day.
Click to expand...
Sounds likely. What I'm struggling to understand is why my hba1c has gone up so much despite eating very low carb. I didn't think it would be necessary to actually be continuously in ketosis in order to not be prediabetic.
I had wondered if being in ketosis for years can cause the body to be extremely sensitive to glucose once enough carbs are reintroduced to slip out of continuous ketosis, and if so, is it permanent.
 
Surely you would have to purchase a Keto monitor and measure your ketone levels to understand if you are actually in Ketosis? HBA1C is not a measure of Ketosis. It may be that you have to find your Carb tolerance level and increment upwards from 20g ( +5g) and measure you BG to understand what spikes your Glucose.
 
I take it you mean 5.7% on the DCCT scale - that's equivalent to 38.8mmol/mol. See the converter here:

https://www.diabetes.co.uk/hba1c-units-converter.html

What you're reporting aren't pre-diabetic figures.

Your earlier 5.1% reading equates to 32.2mmol/mol. The "normal" blood glucose range, which is the blood glucose levels of almost all non-diabetic people, is 38-42mmol/mol, or 5.6% to 6%.

My A1c has wobbled about between 34 and 38mmol/mol for three years, without me changing anything. Bear in mind as well that there is a 5% total allowable error on an A1c test - so it's possible your 5.7% result is up to 0.3% out.

It is also possible that if you're exercising more, your body has decided that it needs more available fuel and your liver is upping the amount it puts into your bloodstream.
 
Type 2 Diabetes never goes away in my opinion, meaning you still have to eat low carb enough to control it for the rest of your life. This is why we say that remission of Type 2 diabetes is a marathon, not a sprint.
If it took doing under 50gms of carbs per day to get your BG as low as you wanted back 1yr ago or so, it will always be like that and may need to go lower carb still, even though for a while it may seem that it is cured.
It's the insulin resistance and the health of the Beta cells in which make insulin in the pancreas. They tend to get slightly worse rather than better. If they do get better, then usually it is just temporary. Cardio exercises don't compensate for this, which is why I say you can't outrun a poor diet.

What I'm painting here is a realistic picture. If you want the optimistic picture then there are a very few, mainly in the other UK diabetes forum who claim they are 'cured' and can eat like they used to before diagnosis. I have seen no proof, so I think they are either mistaken or trying to fool other people.
 

I know hba1c isn't a measure of ketosis. At no point have I said it was and I'm not sure why everyone is getting focused on talking about ketosis.

Maybe I wasn't clear enough. To make it really basic: I am surprised my hba1c has gone up so much with such a small increase in carbs, especially since I have been exercising much more. I am also surprised that anyone, particularly someone who has not been diagnosed with diabetes can't keep hba1c within normal range on less than 50g carbs a day.
 
ianf0ster said:
@KennyA I think you'll find that 38 in UK measurements is pre-diabetic in the USA. Only just, but pre-diabetes!
View attachment 61943
Click to expand...
OP is in the UK and so are we. There are currently five definitions of prediabetes and setting the bar lower appears to make no difference.


I'm also attaching a graph showing the normal distribution of HbA1c in a non-diabetic population - who would presumably be surprised to find that they are now (according to the USA) prediabetic.
 

Attachments

  • HB.PNG
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I understand exactly what you are saying! I’m heartbroken that after three months of eating under five grams of carbs a day my A1C went from 6.0 to 6.3. I am beyond frustrated! My LDL also went sky high, high enough for my doc to text me with her concerns. So, that didn’t work. I’m adding a few happy carbs back in the form of berries, yogurt (full fat), avocado, and some veg. I’ve eaten grain free and sugar free for years and it’s quite obvious that my pancreas is failing. I’m a gym rat, slight build and really healthy….except for that darn blood sugar. I really need to find a way to be tested for antibodies (it’s a problem in Canada).
I hope you can find some answers for yourself.
 
Everyone’s body and tolerance for carbs to stay in keto is different. You just have to find your level.
 
I would get another A1C in a few months to confirm it's not just a fluke. If it's still the same, then it could be a few things. Maybe your beta cells are putting out less insulin than they used to. Maybe you're just very sensitive to carbs, irrespective of exercise. Maybe the exercise is raising cortisol, which is causing the liver to create more glucose via gluconeogenesis to meet energy demands. Did you get any other tests besides the A1C? Is your weight the same? Do you feel well otherwise?
 
I’ve just started the Zoe programme here in the UK. It helps you to understand how what you eat is effecting your blood sugar and blood fat and then make adjustments that are tailored to your biology to flatten your blood sugar.
 
I've had similar issues. I'm on a very low carb diet (weighing out everything, under 20g a day), and have been very strict over the past 6 months, plus a 36 hour fast once a week. Just had by hba1c done and instead of it lowering as I thought it would, it's risen to 44. As a side note, in the 3 months prior to my bloods being taken, I'd stayed off alcohol completely.

I was diagnosed diabetic in 2016, and have had HbA1c readings as low as 34 since.

It's a head-scratcher.

I did find this info which I'm not allowed to post a link to as I'm a newbie, but it is on a website called Marks Daily Apple. It discusses a high HbA1c with low blood sugar. It basically says that:

• for every 1% rise in blood sugar, red blood cell lifespan fell by 6.9 days.
• hba1c is measured using red blood cells
• in those with better blood sugar control, red blood cells lived longer, and therefore had more time to accumulate sugar and give a bad HbA1c reading

I'd be interested in anyone's thoughts on this - have you heard of this before?
 
@CW84 Hi there, this doesn't seem to have been asked but have you been ill in the last 2-3 months, even a 'mild' virus, covid or allergic reaction could put your blood glucose, and hence HbA1c, up. Taking some medication like steroids or antibiotics can also increase BG, so there could be a non-diet, non-exercise, 'non-catastrophic ketosis failure decline into diabetes' reason why it has gone up a bit!

Are you having NHS tests or going private? I am not sure on the 'reliability' or equitability of private tests, but know my surgery would not be testing anyone regularly if they weren't already diabetic or were presenting as diabetic, so maybe your results have come from different labs?

Just wanted to through this into the ring.
 
According to Bilous and Donnelly, there are a few people for whom HbA1c doesn't work. There can (chapter 3) be spurious results for example where there is iron deficiency, haemoglobinopathies, renal failure, or amongst different ethnic groups.

The problem is that the alternative tests have their own issues. B&D quote the US NHANES study where 1.6% of the population had HbA1c >6.5% (>48mmol/mol) but 5% of those would have been undiagnosed by a fasting plasma glucose or an oral glucose tolerance test. FPG is said to be problematic because the subject needs to fast (and presumably there is low compliance).

Conclusion they draw is that the HbA1c isn't entirely perfect but is the best there is.


@Ian_White
You mention

As a side note, in the 3 months prior to my bloods being taken, I'd stayed off alcohol completely.

Alcohol tends to suppress blood glucose levels because in the system it interferes with the liver topping up ("trickle-charging") your blood glucose. It is possible that your liver became a bit more active doing this top-up in the three months before your last test, in the absence of alcohol.
 
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