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Post meal spikes.

TOMJC

Well-Known Member
Messages
69
Type of diabetes
Type 1
Treatment type
Insulin
Hi guys,

I have long been struggling with post meal spikes. Generally about 20 minutes after my meal I can spike by up to 8-10 mmol. This will drop back down to the same level as pre meal within 4 hours. Generally my dosage appears to be correct as my pre and post meal levels are what they should be. However now I know about the spike I want to try eliminate and eliminate it as I generally feel pretty rubbish after meals and do not think it is healthy.

I have tried injecting my Novorapid early (up to 45 mins, depending on BS level) which definitely helps but this is generally fairly unpractical especially at work.

Does anyone else suffer from this? Does anyone know if any of the other short acting insulins work quicker than Novorapid? I was always under the impression that these operated almost immediately but clearly I am mistaken!

It is probably worth nothing that I use the Freestyle libre where the spike is fairly apparent. I'm not sure how noticeable it would be without it, I only really know I have had the spike for the last few years because I have been feeling high and the odd test 1 hour after eating has confirmed it.

Many thanks for any help.

Tom
 
Hi Tom,

I was going to suggest injecting in advance, but I see you've already tried that. For me, when I was on Humalog, the difference in injecting in advance for my breakfast was very big - 5.6 two hours after when injecting in advance, 11.2 when injecting just before eating. How much of an improvement did you see when injecting in advance?

The other thing I've found is that if I'm even slightly active after a meal, I'll have a better blood sugar. I always try to keep active after eating, even if it's only walking up and down the stairs tidying things away.

Do you spike after every meal or only certain ones?
 
There is also the question of what you are eating exactly. Twenty minutes is very fast digestion. It is possible to slow down your digestion by eating protein and salad-type stuff in the same meal. And by eating the low-carb stuff BEFORE you eat the carbs. A lot of people on here will advise LCHF, but so far I manage like this.
Also, why are you testing 20 minutes after meals? There isn't even any data available on non-diabetics 20 minutes after meals. I test about an hour after, and that's considered early. 2 hours after is recommended.

Plus, you want to be in range after 2hours. If your blood sugar is 4.0 before and 7.8 two hours later, you're in range.
 
I agree with @azure on the activity point. I know it's not always possible (or practical) but being even remotely active after eating has a huge impact on spiking for me. I find that if I am having a lazy night and just veg out and don't move after eating I will generally spike no matter what, whereas if I'm even a little bit active it really helps.

@RuthW - with Freestyle Libre you can easily see what's happened at 20 minutes after eating, without proactively thinking of testing. Whilst it's all well and good being 4.0 before and 7.8 2 hours later it's not good if you had a double-digit peak in the time in between....
 
Before reading this I expected to read that your BG levels were going 12 upwards. I wouldn't call 8-10mmol a spike, you're doing great - I wouldn't worry if I were you!
 
All the QA insulin's work in very similar time scale, Apidra might be slightly faster at working than Novorapid but whether you would notice the difference is another matter @TOMJC.
 
It's mainly lunch and breakfast where I spike. since moving on to the libre I have discovered I suffer from dawn phenomenon so that will mess up my mornings readings. I can catch this generally pretty well with a 3 unit does of Novorapid on top of but need to give it a good hour or so before I eat to avoid a spike.

@azure I have found a huge difference. For example today and Friday I have had the same meal (70g CHO) and injected the same amount each time. My activity levels were pretty much the same as well. On Friday I injected when eating and spiked from 6 to 16 before returning to about 5 four hours later. Today I injected 45 mins before eating and went from 5.6 to 6.5 over the four hours peaking at 9. My graph was almost a perfectly flat line.

@RuthW I do eat very healthily and have a reasonable mix of protein and salad. This doesn't really seem to have much impact on my blood sugar spikes. I also agree with @pinewood that whilst you want to be in range 2 hours after eating, the spike in the meal should also be avoided as the spikes could be causing long term damage which I am obviously keen to avoid.

@pinewood, @azure exercise definitely helps. Unfortunately not often feasible during the day. In the morning after breakfast I can see it does help limit the spike by maybe a mmol or two if I go for a 20 min walk as part of my commute. Nothing drastic but better than nothing.
 
Before reading this I expected to read that your BG levels were going 12 upwards. I wouldn't call 8-10mmol a spike, you're doing great - I wouldn't worry if I were you!

Sorry I meant they were spiking by around 8 to 10 mmol. Would be very happy if they just moved from 8-10!
 
Sorry I meant they were spiking by around 8 to 10 mmol. Would be very happy if they just moved from 8-10!


Are your injection sites OK? Also if this has just been happening recently then you might want to try changing your insulin cartridges.
 
Yes insulin sites are all ok. I don't think it's the insulin cartridges. My guess would have been this has been happening for quite a while (based on how I have felt after meals and the occasional test I have done one hour after eating). It's only since I got the CGM that I have been able to see hard evidence of the spike.
 
This is sadly a problem of eating carbs.

You can eliminate this spike almost entirely by eating no, or low carb meals. Any meal with carbs will have a spike associated with it because, although you are injecting the correcting amount of insulin, you cannot accurately know when your meal will spike so you cannot match up your injection profile to cancel that out.

The less carbs you have in a meal the lower the spike will be, Thats the best advice I can give - Eat less carbs, always.

Think about it, mess around with some low carb meals (like 10-20g per meal) and inject 20min or so before you eat. You will notice your spike is very little, sometimes non-existent.

Best of luck
 
I read in 'think like a pancreas' that by having vinegar/something acidic with a meal helps with post meal spikes. I haven't tried this though!
 
This is sadly a problem of eating carbs.

You can eliminate this spike almost entirely by eating no, or low carb meals. Any meal with carbs will have a spike associated with it because, although you are injecting the correcting amount of insulin, you cannot accurately know when your meal will spike so you cannot match up your injection profile to cancel that out.

The less carbs you have in a meal the lower the spike will be, Thats the best advice I can give - Eat less carbs, always.

Think about it, mess around with some low carb meals (like 10-20g per meal) and inject 20min or so before you eat. You will notice your spike is very little, sometimes non-existent.

Best of luck
I respectfully disagree.

It's not necessarily how many carbs you consume, but rather, how many carbs are digested at one time. This is where the glycemic index comes into play and why it's extremely important to understand how different types of carbohydrates can affect you.

Think about it like this: why do people recommend orange juice or glucose tablets to treat hypos? It's because they're rapidly digesting and quickly converted into glucose.

Would eating 30g of fiber treat that hypo? No, because our bodies cannot absorb fiber
Would eating a bowl of brown basmati rice treat that hypo (quickly)? No, because it's a low GI food. It takes too long to be absorbed.

The point is this: 10g of carbs digested in one hour is going to spike your blood sugar quicker than 15 grams of carbs digested over three hours. It's about managing the types of carbs you eat rather than avoiding them altogether.
 
Just as an aside, if I eat brown basmati rice I have to super bolus for bit as the carb absorption rate is incredibly high. It's almost as steep a climb as bread!
 
Just as an aside, if I eat brown basmati rice I have to super bolus for bit as the carb absorption rate is incredibly high. It's almost as steep a climb as bread!
I probably could have used a better example. There's actually a lot of discussion about basmati rice. Some people have mentioned there are some brands that measure extremely high on the GI while others measure very low.
 
Like it's already been mentioned it may be due to the type of carb your eating. Eg if a non-diabetic drank lucozade their levels would easily reach 8-10. It's your level after 2hours that matters. If your worried about it in terms of your health then choose lower GI carbs that arnt fast acting.
 
Thanks for all your help. For those interested my solution is as follows:

Breakfast: 3 units Novorapid to counteract morning rise and then a protein only breakfast.

Lunch: normal dosage 25 mins before if BS < 7, longer if above 7.

Seems to have worked perfectly so far, CGM showing pretty flat graphs.

Many thanks for all your help!
 
I respectfully disagree.

It's not necessarily how many carbs you consume, but rather, how many carbs are digested at one time. This is where the glycemic index comes into play and why it's extremely important to understand how different types of carbohydrates can affect you.

Think about it like this: why do people recommend orange juice or glucose tablets to treat hypos? It's because they're rapidly digesting and quickly converted into glucose.

Would eating 30g of fiber treat that hypo? No, because our bodies cannot absorb fiber
Would eating a bowl of brown basmati rice treat that hypo (quickly)? No, because it's a low GI food. It takes too long to be absorbed.

The point is this: 10g of carbs digested in one hour is going to spike your blood sugar quicker than 15 grams of carbs digested over three hours. It's about managing the types of carbs you eat rather than avoiding them altogether.


Of course i agree, i was trying to avoid a long biology lesson explaining the GI lol

Also, when you count carbs you should be subtracting the fibre because you stated the body cannot digest it. So when I say 'carbs' most people on this site do not include fibre.
 
Also, when you count carbs you should be subtracting the fibre because you stated the body cannot digest it. So when I say 'carbs' most people on this site do not include fibre.
Careful - US and European differences! Confusion abounds...

For those who don't know, in European nutritional information, total carbs is the value you use - it doesn't contain any fibre.

For those who care, in the US you have total carbs and fibre as separate measures, and total carbs includes fibre, so to calculate carbs you take fibre from total carbs. Some packs show net carbs.

Just a point of information for those who don't know the difference.
 
Careful - US and European differences! Confusion abounds...

For those who don't know, in European nutritional information, total carbs is the value you use - it doesn't contain any fibre.

For those who care, in the US you have total carbs and fibre as separate measures, and total carbs includes fibre, so to calculate carbs you take fibre from total carbs. Some packs show net carbs.

Just a point of information for those who don't know the difference.

Wow, yeah i had no idea.

In Canada on our label we have "Carbohydrates" as one number and then a sub category showing the amount of sugar, and fibre and to calc what we need to inject us in Canada / USA have to subtract the fibre from the carbohydrate number and use that.

If I were to make decisions based on just the Carbohydrate number on packages i would hypo after almost every meal!

Thank you for point this out to me lol
 
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