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Higher blood glucose after breaking a fast?

G

Guilty

Well-Known Member
Messages
151
Location
UK
Type of diabetes
Type 2
Treatment type
Diet only
I eat twice a day (lunch and dinner). And the highest point of my blood glucose is consistently higher after lunch (avg 8.8 mmol) than dinner (avg 7.5mmol).

Has anyone noticed higher blood glucose after breaking a fast?

Or is this likely to be just based on time of day / hormones etc.?

My meals are pretty consistent across lunch and dinner. With similar physical activity after eating (walking the dog).

Just wondering if this is something like the second meal effect and it might be better for me to have less carbs at lunchtime?
 
Have read that the best foods for breaking a fast is really low carb, eg salmon/tuna and salad. Have also read that sometimes, if you're new to fasting your pancreas can go into panic mode thinking you're starving, just like it does re the 'dawn phenomenon'.

Over the past 6 months I've been on keto, my pancreas appears to have settled down somewhat and that 'dawn phenomenon' isn't now much different from my bedtime BG reading.
 
I have to assume that you are only testing before a meal and then 2hrs after 1st bite - tests before that point aren't much use, since even non-diabetics get large spikes in BG, just that they don't last as long. Some of us Type 2 's are more carb sensitive in the mornings than in the evenings and for others it's the other way around.

I often find my highest BG is before I break my fast (both when eating 2 meals a day and when eating 1 meal per day).
I eat low carb 20gms to 40gms per day, so before I eat my BG is all coming from my liver - not my food.

Dawn Phenomenon is still quite a large factor for me despite being 'fat adapted' and in remission for nearly 4 yrs.
It's when I eat a low carb meal that my liver decides I don't need any more glucose to keep me fueled.
 
The actual number is not as important as the difference between pre meal and 2hr results.
Many of us experience rising blood sugars until we eat, our livers taking the opportunity to get rid of some stored glucose, so it would follow that if lunch is your first meal , you could be starting from a higher level than you are at dinner.
Other possible reasons are that your lunch has more in the way of carbs than your dinner, and for some reason we seem to be more insulin resistant earlier than later. Don't understand why that would be but things seem to have less of an impact on my levels later on in the day.
 
Thanks. I think I might be more insulin sensitive at dinner time then. I'm using a libre at the moment and looking at it my 'dips' from walking also seem bigger after dinner. So that would also tie in with being more sensitive at dinner time?

I feel my diabetes is very well controlled at the moment. But I do want to make any tweaks I can to maintain my health. As I'm well on the road of diabetic complications due to years of undiagnosed high blood sugars (and a few years of having my head in the sand).
 
As others have said, sounds like dawn phenomenon is at play. Ian's suggestion of a small, low carb snack is the only consistently reliable "fix" I've found works to halt it, although my dawn phenomenon is increasingly inconsistent and doesn't cause a continuous rise every time when fasting. My layman's understanding is that our bodies perceive an empty stomach as "will be going out to hunt soon and might have to fight off sabre-tooth tigers on the way", so your liver primes your body with the glucose it needs for energy. On the one hand, your BG increases, but on the other then if you have a fatty liver then it's pushing your liver to use its stores - as with many diabetes issues, swings and roundabouts!
 
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