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Prediabetes Fasting blood glucose - time of testing

Dexie1

Active Member
Messages
31
Type of diabetes
Don't have diabetes
Treatment type
Diet only
Hi there

Is the only reason they recommend testing your fbg first thing when you wake because of the time since your last meal? Making around 8 hours of fasting?

Reason I ask is because many people, myself included, suffer from the dawn phenomenon. I do the 5:2 diet and don’t eat at all during the day leaving my 500 calories to my dinner. If I test before dinner having had only water and my last meal / snack around 9pm the night before my bg is usually around 4.5-4.9 most of the time compared to high 5’s first thing in the morning.

This always worries me but I’m thinking I’m getting a more accurate reading which is not affected by the dawn phenomenon.
 
Dexie1 said:
Is the only reason they recommend testing your fbg first thing when you wake because of the time since your last meal? Making around 8 hours of fasting?
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To the best of my knowledge yes.
And to try and avoid anything that might elevate bg levels I have heard people say even a morning shower can raise there bg levels. So although you can go 8 hours during the day with out eating, your still active which can elevate your reading.

Taking that into account 4.5-4.9 perhaps being elevated due to day to day activities and even high 5's due to dawn phenomenon there still fairly low levels of bg.

Hopefully the next person to respond will have a more in-depth knowledge of blood meter readings.
 
Don't worry! Your readings are excellent. I think the reason people on here test and post fbgs is to give us a bit of encouragement and motivation in managing our condition.
HbA1c tests at the GP surgery usually require us to fast for at least 10 hours before the test.
 
Dexie1 said:
Is the only reason they recommend testing your fbg first thing when you wake because of the time since your last meal? Making around 8 hours of fasting?
Click to expand...
Not really it just gives you a start figure for the day which comes naturally after your sleeping fast. From there you can monitor where your blood sugars go.
It depends on what you are using your readings for. If solely for assessing the impact of food on your levels then you probably don't need it. If you want to get an overall picture of what your blood sugars are doing then record it. I have developed a routine now where I get up, pee, weigh myself and take my bloods before starting the day.
 
Your numbers are good, nothing to worry about there. After 20 months of LCHF, currently about 40 to 50 gm carbs daily, my BGs have hardly changed, 6.5 fasting, 5.3 before meals, 5.6 after meals (90 day averages). Unlike some people, showers in the morning don't affect my BG, in fact it seems I can only raise BG by having a carb heavy meal, nothing short of not eating will lower it!
 

First, I know the dawn phenomenon is, but I really don’t see were your problem is. With a dawn ogenomen I would think of much higher fasting blood sugar.
5-5.9 mmol in the morning are fine and normal, and not even prediabetic. So even if you had lower blood sugar before bed it is still normal to have between 4-5.9 mmol in the morning.

Can I ask how you were diagnosed as prediabetic?
 
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