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Type 1 Post meal spikes

MisterMints

Well-Known Member
Messages
49
Location
United Kingdom
Type of diabetes
Type 1
Treatment type
Insulin
How long does your post meal spike tend to last?

I can't get my head round mine! Since getting my Libre I've been much more aware of what is happening with my glucose levels at all times, and I'm finding my glucose spikes after eating to be a bit confusing.

Today for example, I had beans on toast for lunch (full can, 2 slices of Tesco oat and barley bread = about 97g of carbs) and injected for it. Ate that at 2 pm, and at the time of typing, its quarter past 4 and my glucose levels are still rising (currently at 9.7 according to the Libre).

I was under the impression that around 2 hours after eating glucose levels should have pretty much returned to normal, but its not uncommon for mine to stay high for 3 or 4 hours afterwards.

I'm on NovoRapid, about 12g or carbs per 1 unit, I rotate my injection sites, and I can't seem to ever get it to work. If I inject 1 unit less I'm high for 5+ hours, if I inject 1 unit more, the high lasts a much shorter time but I will end up hypo. If I inject according to my insulin:carb ration calculations I am like today and still going up 2 hours later, with an expected drop to normal in another 1 or more.

What's going on?

What are your post meal rises like?
 
Hi MisterMints mine usually are back in range like Karen8967 by the 4 hour mark, but I struggle with baked beans so find myself giving more insulin per 10g carb ratio!!
 
I have been monitoring mine a lot lately as my bloods are due in 2 weeks and I so want to prove to my diabetic nurse that low carb is the way to go and mine are still high at 2 hrs but by 3 hrs I’m usually back to where I was before eating. I suppose we are all different .
 
MisterMints said:
What's going on?

What are your post meal rises like?
Click to expand...
One thing I'd say is that Libre gives you a good indication of how slow insulin is. Firstly, for meals like Beans on Toast, a 20 minute pre-bolus often isn't early enough and I need a 40 minute pre-bolus, but you'd need to experiment with timing.

Secondly, beans on toast is, for me, one of "those" meals, in that the content of the meal doesn't match the nutritional information on the packet. I think the protein content of the beans added to the carbs causes a prolonged higher level.
 

Hi tim,

This happens with most meals though - beans on toast was just the example from yesterday's lunch.

My usual lunchtime meal is sandwich (in a wholemeal roll, with "non/low carb" fillings e.g. ham and cheese), packet of crisps, bit of fruit (usually an apple, banana or a couple of small oranges like tangerines) and maybe a biscuit like a Kit Kat or Twix. This is usually around 70g but the high still lasts for hours afterwards. The opposite sometimes happens, where I do stay high for hours, followed by a very rapid crash (assuming I eat at 12:30, this crash tends to start at 1630-1700)

As it happens, I did inject about 45 minutes before eating yesterday. Completely by accident, and I know this is terrible practice, but injected at 1315, had a quick shower while I let that do its magic, and then got distracted by an email coming in and the cat wanting her lunch. By the time I put the beans on the hob it was just before 2pm.
 
DAFNE taught me that beans were actually not to be considered fully due to their slow release......but I normally take for half of the stated carbs....and that seems to work a treat, even on the pump....

Maybe the 45 minutes wasn't the right timing and the insulin peak missed the meal peak......what happened after? did it come down in range again and at what time?
 
Have you done any basal testing recently? It sounds as though now you have the Libre, it's an optimal time to do it.

If your meals result in sustained postprandial highs, either your I:C ratio is incorrect, or your basal amounts aren't quite right. It's often best to go right back to the start and see where basal is if you're having issues with meals.
 

The day, and this morning, panned out like this:

1315 - Inject NovoRapid
1400 - Eat beans of toast
1500 - Starts to rise
1800 - Reaches peak of 11
1815 - Inject half a unit of NovoRapid
1900 - Went for a 1 hour run
2100 - Hypo and slightly over compensated with Jelly Babies
2130 - Ate a late evening meal (homemade moussaka - about 40g carbs), injected 6 units of NovoRapid to counter the already starting to rise sugars
2200 - Sugars spiked at 18.7, injected another 4 units of NovoRapid
2300 - Reading 16.1 and falling slowly
0230 - Hypo, 4 Jelly Babies and a chocolate HobNob. Read LO on Libre so just below 2mmol. Didn't test blood as it was the middle of the night and I felt like ****
0700 - Reading 13.8, injected 2.5 units of NovoRapid
Right now: stable at 5.6
 

I haven't. I've not really been sure how to go about doing it really
 


So at 1800, you are saying that this is the peak of the novorapid? nearly 5 hours after injecting.....that seems unlikely, or not something one would assume was the case.....is it not the case that the 11mmol is actually the end result after your insulin has expired....? which leaves the issue being the carb count or insulin/carb ratio....

the rest of the day is quite difficult to break down as there were hypos, hypo treatments [over treated], exercise and so on....a minefield.....

how much was the overcompensation of jelly babies.....? you could have included that in your late meal dose...also you corrected an 18.7 half an hour into your last injection.....that's very likely responsible for the hypo later........

but its really just the lunch you were asking about......so one thing at a time.....
 


The chart after lunch looks more like this:


IGNORE THE TIME ACROSS THE TOP: I hadn't updated the time on my hand held reader to everything is one hour ahead of the actual times these scans were done.

So, you can see the dip after 1400 because of the 45 minute gap between injecting and eating and then a rise from just after 1430 until just after 1600 where it rises very slowly and the line flattens out.

Ever so slight surge until just before 1800, then the small drop back into range as a result of the half unit I injected. Flat/slight rise while I was running until 1930 when it took the sudden plunge into hypo (I had 2 lots of 3 Jelly Babies while running, about 10 minutes apart)

After hypo you can then see the rise to 6.7, 6.8, then 10.7, 13.3 and up. I'm not quite sure why the 18.7 I mention doesn't show up on this report as it does on the one within the LibreLink app on my phone.
 

So, as mentioned the 45 minute pre bolus probably isn't ideal, but this isn't the norm you mentioned..... on this occasion though the peak of the food, which may be delayed because of the beans, was missed by the insulin peak...

Normally you expect, or want, to see the BG peak up 1,2 or 3mmol at the 1.5-2 hours mark, it will then start to drop off back in to range for the remaining duration of your dose...

Have you established how long your doses last....?

I seen basal testing being mentioned and this is very important......if its not correct then all this speculation is pointless....
 
On the dose length question I only have a rough idea and this is based on the previously mentioned 1630-1700 rapid fall which is probably wrong.

Because my glucose seems to peak and stay high for 3-4 hours, my assumption was that the NovoRapid lasts for about 4.5hrs in my system.

If there is a way to definitely test this though, I'm all ears
 
I suppose its not an exact science...but looking to see when your glucose levels stop moving up or down would confirm it......

obviously this depends on a correct basal dose.....
 
I think you may be correct on the basal points.

Last night/this morning for example; I injected my Tresiba at 10pm like normal and went to bed, woke up at about 7am with a slight hypo reading of 3.7. Ate 3 Jelly Babies and snoozed for a bit. Tested again just after 9 and my reading was 7, tested again at 10:30 and was back down to 4.1 so ate 2 Jelly Babies and I rose to 6.8.

Just tested again (noon) and I'm at 5.4. These kinds of readings are not all that uncommon in the morning for me, but the flip side is if I inject less Tresiba I tend to run around the 8-9mmol mark until lunch time.

I was going to try a basal test today, but the hypo kind of ruined that. However, not all bad news if I can see my sugars falling after eating even without injection NovoRapid and what I can learn from that.
 
It sounds like a split dose might be needed so you can cater for both your overnight and daytime differences separately..

but then Tresiba is meant to be a single, long acting dose.....

see what the basal testing uncovers....
 
Thank you for publishing this wonderful informations
 
Your pattern is very like mine and a lot of other t1s. Not all keep a flatline and that is ok.
 
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