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Normal A1C with two high FBG

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roy2200

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Hello,
I am new here and really appreciate your help!
Today I got the results of the lab test :
A1C was completely normal ( 34 mmol/mol ) but the fasting blood glucose test (FBG) was high in two different days.
In one day it was 7.2 mmol/L , the other day 7.5 mmol/L

I normally eat my main meal at around 10:00 PM and then have a cup of tea with some suger.
I fasted 12 hours and then did the test the next morning.

I am 29 y/o. My weight is about 80 k.g . There are no symptoms or anything. I just want to know if I have DM so I did the tests. I totally understand that A1C could give a more clearer look into the Glucose levels in the past 90 days, but still 7.5 is pretty high for a 12-hours fasting levels !

According to my GP, there's no need to worry at all. She thought it might be elevated because I eat my main meal in the late evening, but I am still concerned because high FBG on two different days simply means diabetes. Even if I ate my main meal at that time, 12 hours should be enough to reduce the FBG to the normal range.

Do I need to worry ? what is your advise ?
 
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Relax. In the morning your liver dumps out some glucose to give you energy to start the day, it's not the remnants of the last meal and tea you're seeing. Is it a tad high? Maybe. A little bit. But if you're stressed, or a restless sleeper, wake up in the night for whatever reason, have nightmares or whatever, that could trigger a dump early. Maybe you had a cold, that can crank up fasting glucose too. A few fasting numbers don't automatically mean diabetes, it just means you have to get a HbA1c done, which you did, and those numbers were excellent.

If you remain uneasy, get the HbA1c repeated in half a year or a year from now. For the moment though, you're not diabetic. Not even prediabetic. (Which is between 42 and 48). We can't diagnose on here, but that much I can tell you. Is there a specific reason your mind went to T2 to begin with? Any issues, or it running in the family or something?

Anyway, you be good to yourself eh. And for now, nope... No DM.
Jo
 
JoKalsbeek said:
Is there a specific reason your mind went to T2 to begin with? Any issues, or it running in the family or something?
Anyway, you be good to yourself eh. And for now, nope... No DM.
Jo
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Thank you for your reply, there is no spesific reason, it's just my Master's thesis was about Diabetes and since then it is in the background of my mind. I did some tests on another issue and my Glucose was in the 7s, although it was not marked as high because they classified it as random, I was partly fasting on that day. This triggered endless what-if scenarios especially after I have done the 2 fasting tests.


JoKalsbeek said:
A few fasting numbers don't automatically mean diabetes, it just means you have to get a HbA1c done, which you did, and those numbers were excellent.

Jo
Click to expand...
So, let's assume I repeat the FBG several times and it is always high, what would be the scenario with normal A1C ?
My concern is that the diagnosis criteria for DM always say: 2 high FBG OR high A1c OR... etc
so according to those crietera I should be diabetic !
I eat normally once a day, can this mean for example is my Glucose always fluctuates from normal to high (after the meal), can this affect the A1C reading so it seems normal ?

I don't exercise, my lifestyle is sedentary and my food intake is just normal, I don't eat that much , not much sugary products.
Can I be diabetic (insulin resistent) but my glucose is always normal becuase of the very low food intake, which meant normal A1C ??
 
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It is like this for me! fasting 7.2 Hba1c 35, then 6.4 & 25, 6.4 & 26,
OGT 7.2 before, 8.1 after. No symptoms, was given 3 diagnoses - prediabetes, diabetes and no you don't have diabetes.
My Hba1c goes up and down with my weight.
 
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I don't know what you normally eat, "normal" means exactly nothing to me... You mention no sugary products, but what does end up on your plate? If you're fasting most of the time that could bring down numbers, yes. If you're eating a ketogenic or close to that diet, then that could bring down numbers too. In your study, did you also read about how to stop T2 in its tracks? Because I've basically put mine in remission by low carb eating and fasting. No new complications, and all but one fixed from when I walked around with high blood sugars for years before diagnosis. So diabetes isn't the monster it's made out to be, if you know how to tame it.

If you want to know how you're doing with insulin resistance/response, you can request an extended OGTT. (Oral Glucose Tolerance Test). It shows how your body reacts to a shock intake of sugar. That can answer your questions better than a random person on a forum, because there's no way for any of us to know what's going on. And if you want to start testing yourself, test this way: before a meal, and 2 hours after the first bite. You already know your fasting's a bit up, you might want to check how you respond to meals. A food diary with recorded blood sugars would help.
 
I am really glad to hear you've put yours in remission.
yes I've learned how to prevent or at least postpone the complications of DM, that's why I just want to know if I have it or not, just to know what to do before it's too late.
Today I requested the OGTT , still waiting for the doctors's answer. However, she seems not concerned at all and chances are she would refuse to do it. That's why I am thinking about getting a home kit to measure glucose levels.
 
A doc should consider it even if it's just to take away undue stress from a patient, (as she may not believe something's up) but that's just my opinion. That won't count for anything, alas. But yeah, you can get a meter. And if you test your fasting BG's, test them the moment you wake up. Not gone out to the bathroom or whatever: eyes open, grab meter from the nightstand, stabby-stab-stab, check and go. That way you have less of a chance of Dawn Phenomenon and Foot on the Floor getting in the way of a clear reading.

You do whatever you need to to get some peace of mind, and if at all possible, some proper answers.
 
I'll sometimes get a bit of a blip with fasting levels similar to those two results of yours, but my HbA1cs have been pre diabetic levels for nearly eight years, and I tend not to worry about what my liver thinks I need to get me started in the morning. And I'm an ancient, overweight, inactive old lady....

IMO your two random fasting results mean very little over a three month or so period that's given you a nice low and definitely non-diabetic HbA1c. But if you're really concerned then get yourself a Freestyle Libre sensor or two to use for a while to see exactly what sort of patterns/levels you get 24/7. A meter's great for wake up fasting and pre & post meal spot checks, but the sensor's logs will tell you a whole lot more about what's exactly going on.
 
Hi there. I just joined diabetes.co.uk. I can relate to your question as I was going to ask something similar!
I’m female 30s and I have not been diagnosed with diabetes but am concerned about my blood sugar. Ever since having glucose in urinalysis at the drs. I got a blood glucose monitor and periodically check.
My last HbA1c was in July and was 35. The year before 32 (was eating low carb high healthy fat for health). Dr wasn’t bothered.
I need to gain healthy weight as I struggle to gain weight. If I eat a portion of carbs (approx. 30g) at a meal, 2 hours after blood glucose is over 7.8 mmol.l. I would also end up with glucose in urinalysis.
I am an advocate for a low carb lifestyle and have been following the low carb movement for a few years. I have a health education background and understanding of the science. But I’m still concerned. I am a low weight and need to gain healthy weight. I obviously don’t handle a carb load well. I feel fatigued after carbs too.

We all have a personal carb threshold (ref. Dr Eric Westman). Might be you need to figure your personal carb threshold to keep staying healthy? And periodically check your blood glucose an hour or two after meals to see if it spikes too much?
 
Your main meal is circa at the time when your circadian rhythm is getting ready for sleep. Others may disagree but I would expect to be in the late 4's or early 5's under 30 years old. You may well have cleared the glucose from your meal and be getting a liver dump as well. Again I am a little left of centre as I tend to go with the Ted Naimans' Marty Kendalls' of the lower carb movement; i.e. the higher number may also be too much fat in your diet providing a long tail the next day.

I am guessing that you have some insulin resistance, which has not translated fully to diabetes.

I would make lifestyle changes, such as walking (especially after meals), having a last meal somewhere between 15:30 and 18:00, eating low carb or keto, resistance training and most importantly consistent qualitative sleep. Even if you implement one of these at a time and measure the outcomes, benefits are bound to result.
 
Reactions: WMF
roy2200 said:
A1C was completely normal ( 34 mmol/mol ) but the fasting blood glucose test (FBG) was high in two different days.
In one day it was 7.2 mmol/L , the other day 7.5 mmol/L
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You need to know what your fasting BG is during the day as well as from a lab test.
Getting a meter is sensible.
Once you have that and have tested a bit, getting a Freestyle Libre will give you a much clearer picture of what goes on over a 24 hour period.

An HbA1c of 34 mmol/mol is roughly equivalent to a finger prick of 5.8 mmol/L
https://www.diabetes.co.uk/hba1c-to-blood-sugar-level-converter.html

If your average BG is, say, 5.2 mmol/L with just a morning fasting spike of 7.2 mmol/L they you would get a normal HbA1c quite easily, I would think.

Dawn Phenomenon doesn't mean that you have diabetes, but it would be good to get a full 24 hour profile from a Freestyle Libre to confirm your normal BG profile.

As an aside, T1s can get very good HbA1c results by running dangerously low with big spikes from meals.
This is one reason that time within range is now considered a better guide to good control.

Get some results; this should hopefully reduce the speculation.
 

If you feel carbs aren't doing you any favours, you might want to up the calories rather than the carbs. Quite a few T2's aren't overweight, and have no weight to spare. Yet they can still follow a low carb lifestyle, if they just eat 3 square meals and 3 snacks a day, rather than incorporating intermittent fasting and such... All low carb meals and snacks, but just a matter of eating more, and more often. I don't know if that's workable for you, but maybe something to consider?
 
Reactions: WMF
Hi. Thank you for your reply. It makes a lot of sense and is very helpful. I will try to up the calories while staying low carb. I tend to eat twice a day and don’t snack. Any tips on increasing appetite? Food choice a bit limited because of other health issues.
I lost weight without it to lose when I went on an elimination diet because of health issues. My diet is restricted because of a few true food allergies (main ones being wheat, egg, meat, shellfish - fortunately I love fish!). I was intolerant of milk, cut out dairy for a while and have been reintroducing slowly, I love cream and butter. See how I go. Thank you
 
UPDATE :
Hi guys, I purchased a glucose monitor and started testing: those are the readings :
- 2 hours after a meal ( pizza ) : 6.8 , I fasted for 12 hours : next morning after wake up (not immediately) : 6.4, after 1 hour of this reading : 6.7
- another day : 2 hours after a meal : 6.8 , 3.5 hours after that meal : 6.4 , next morning : after 11 hours : 5.4 (immediately after waking up )
-another day : before meal : 4.8 , 2 hours after a meal ( fried fries) : 7

so, from what I can see, the spikes in mornings are not related to the meal before. Obviously, glucose levels are rising after waking up ( or not ? )

PS: I normally do not eat breakfasts, I just drink coffee after waking up ( without suger or milk, just coffee), then after 2 to 3 hours : just another coffee, then after maybe 6 to 8 hours, a meal ( usually the only meal ) .

what do you think is happening ?
 
Dawn phenomenon. Your liver dumps stored glucose to help you start the day, gives you energy before your first meal. It's perfectly normal.
 
JoKalsbeek said:
Dawn phenomenon. Your liver dumps stored glucose to help you start the day, gives you energy before your first meal. It's perfectly normal.
Click to expand...
So, do you think it is related to my routine of late meals and no meals before ( approximately fasting ) ?
from what I understand, the Dawn phenomena is more common among diabetic people, what is the reason that I have it ?
 
roy2200 said:
So, do you think it is related to my routine of late meals and no meals before ( approximately fasting ) ?
from what I understand, the Dawn phenomena is more common among diabetic people, what is the reason that I have it ?
Click to expand...
Everyone has it, in diabetics it's just a bit more persistent. So yeah, could just be that you fast in the morning.
 
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