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BG levels through the day

M

Mad76

Well-Known Member
Messages
319
Location
London
Type of diabetes
Type 1
Treatment type
Insulin
Hi all,
Now this is probably a really obvious question, but please bear with me.

Im a bit confused about what should happen to levels throughout day and about spikes.

Typically i start the day arpung 5-6
By lunch its around 5
Dinner maybe 6 -7
Before bed 7

Now i record this and the doc seems fine with it

But i have the libre so i check levels a lot.
After meals after 2 hours it often goes up to 10 or even 11. Then falls back down gradually. I thought this was ok. However ive read on other threads after food it shouldn't increase more than 2 units .

Am i understanding this right ? Is it a problem that it increases this much?
Im thinking i eat too many catbs ot take too little novorapid? But if i take more novorapid then i guess levels would fall below 4 .

Any advice???
 
I’m hoping you didn’t read a T2 diabetes forum for that.
I always spike after food, either insulin hasn’t caught up yet or dawn phenomena in the mornings is doing it’s business.
I know some experienced T1 diabetics have smoothed out their spikes with good timing of their prebolus injection or their pump. If you ate too much carbs and had too little insulin, your BG would be higher than 7 until your next meal or after 4hours.
It’s important to learn about novorapid insulin profile - it works within 10-20mins, peaks at 1-2.5hrs and lasts for 4hrs. If you fall below 4, that is hypoland for us T1s.
 
The two hour advice is usually aimed at someone with type 2.
Although, the less spikes the better.
If your BG is returning to reasonable levels, this suggests you have the right amount of insulin.
If you are regularly seeing spikes, this may suggest you need to pre bolus a bit earlier. The carbs in your food is hitting your blood levels before your insulin reaches its peak.
Unfortunately, working out how much earlier, is not straightforward as the carbs from different food is digested at different rates. It is normal to see sweeter food affecting your BG sooner (think about your hypo treatment speed) whereas more stodgy or fatty foods will take longer. So, in general, the sweeter stuff needs an earlier pre bolus and the stodgy, fatty food need less pre bolus.
 
Last edited by a moderator:
Hi, @Mad76 , totally agree with what @MeiChanski and @helensaramay are saying.

T1 and T2 are entirely different medical conditions. Even though T2s are mainly thoroughly decent folks (there are some extremists!), their take on it is different, because of the different biology, so it's safest to ignore T2 input as it can be deeply misleading for newly dx'd T1s, to the point that many have, needlessly, become terrified of eating fruit.

In these early days, your bounce to 11 isn't that big a deal, because you came back to a decent number, which shows your bolus amount was right.

That idea of pre-bolusing is something you'll learn as time goes by, matching the time pattern of insulin to absorption rates of food, an incredibly useful technique, but don't run before you can walk.

Here's an example of it from my cgm. 13u 20 mins before a 90g meal. Going by the numbers, I think it was some gyoza, egg noodles chow mein, and either an oat biscuit or a tub of raspberries. If I'd taken the insulin at the same time as the meal, I'd have been sky high, above 10, but that 20 mins pre-bolus to let the insulin get to work meant that levels barely shifted.

 
@Scott-C could you label the different lines on your graphs or tell us the ones to focus on?
I know I add lots of lines to my Libre graphs but my boyfriend finds them all confusing as he doesn’t look at them as often as I.
 
I may well have read it on a t2 forum you are right. I just assumed this might be the case with us T1s too
 
Thankyou for that. Such usefull info!!
 
Thank you for sharing that. I meed to be more aware when im reading T2 stuff! Or maybe justystop reading it at all !
 
helensaramay said:
@Scott-C could you label the different lines on your graphs or tell us the ones to focus on?
I know I add lots of lines to my Libre graphs but my boyfriend finds them all confusing as he doesn’t look at them as often as I.
Click to expand...

I only post from my phone, it's difficult to edit images on it (although I will have to figure out a way to edit out the swearing from Megan's sage advice which I pm'd you and others about before I post it in a family publication!).

The blue dots are the cgm trace, they're the main ones to look at, the green lines are expected insulin iob decline/action, the green squares are carb/bolus interventions, the flittery tiny dots are the inner workings of the predictive estimations of the last carb/bolus input, the yellow and red lines are my 4 to 8 range markers, the hyphenated green and pink lines are my set 5.5 range and 24 hr average.

Go on, Helen, buy a MiaoMiao, you know you want to!
 
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