Why did I get a blood glucose profile like this?

[DancingStar]

I ate lunch at 12pm and I think the rise in my blood glucose to around 10mmol at about 1pm is due to my lunch. I had a cup of tea at 2.30pm but nothing further to eat until my dinner at about 6.30pm. So why did I get that big peak at about 4pm?

I didn't take any correction dose. Would you have done so, bearing in my mind that about an hour later my blood glucose had gone down to around 6mmol?

 

[Bruce Stephens]

So why did I get that big peak at about 4pm?

Don't know. Just your body digesting the lunch, or caffeine in the tea. Or something else mysterious.

I didn't take any correction dose. Would you have done so, bearing in my mind that about an hour later my blood glucose had gone down to around 6mmol?

I might have, but you were obviously correct not to since the graph returned to in range.

 

[Standup]

I get that all the time mainly due to surgery. Assuming this was a one off then was it a high fat content meal that might have taken longer to digest? Less Creon than usual/was needed? Did you exercise?

 

[Proud to be erratic]

Don't know. Just your body digesting the lunch, or caffeine in the tea. Or something else mysterious.

I might have, but you were obviously correct not to since the graph returned to in range.

Hello @DancingStar. My thoughts were immediately in line with @Bruce Stephens comments. Both comments.

I would like to see (know) if this sort of graph occurs often, or just a one-off. If a one-off, then the "mysterious" would be my only conclusion. Something changed, but no idea what. Did you allow yourself to get somewhat dehydrated, perhaps? The weather could support that thought.

If this happens often or periodically, then I'd consider 2 possibilities: timing of bolus in relation to that particular meal; or perhaps your basal is not supporting you as well as it might.

For what its worth, a year or so back I would have (wrongly) applied a correction. My DSN about 12-18 months back most pleasantly, but firmly, reminded me that I have zero pancreas and I should simply not expect my BG behaviour to be regular or predictable and certainly I should not try and meet the "in range" criteria that others might expect. I have been trying very hard to adjust my own expectations as a result of her guidance. Interestingly my Hba1c has not increased significantly as a result of being more relaxed about what my BG is doing hour by hour or week by week.

 

[everydayupsanddowns]

I get a few of these rise-dip-rise traces too from time to time. I find it easiest to try to unpick them if several days seem to show a similar pattern.

For me it feels like the result of the unfolding of insulin action, prebolus timing, and carb absorption over time?

If you ate at noon-ish, then the dose you took for the food, would be (theoretically) most active between 1pm and maybe 3pm, then tailing off between 4pm and 5pm. So the significant drop 3.30pm-6pm might feel a bit ‘late’.

But that would depend on the absorption at the site, and could be affected by all manner of things like level of activity, ambient temperature, blood flow yada yada.

Plus there’s your basal insulin to factor in - is that exactly dealing with the background glucose release you are getting that day (is that glucose release the same as it usually is, or has it been affected by anxiety, excitement, illness, the moon being in Jupiter, or the colour of your socks?). If your basal is over-reaching, or conversely not quite keeping up, you can find yourself with meal doses acting over a ‘slope’ rather than a level playing field.

Then there’s the absorption of the food, and the nature of what it was - plus what your digestive system was up to at the time… fat content… gastric emptying… previous alcohol consumption… fullness of the stomach… gastric hormones.

To be honest, it’s a wonder we ever get any kind of repeatable results with all the variables involved!