Type 1 and BG's suddenly dropping immediately after eating

[AliceBee]

I have been Type 1 for 30 years and currently on a closed loop pump. The last few weeks I have had to delay taking my bolus insulin due to bg's dropping immediately after eating and and going hypo. Previously I would bolus about 10 mins before eating with no issue. I then tried bolusing immediately before eating and the same thing happens. There have been no changes in activity levels, diet etc that I can think of to explain it. It is very strange and is almost as if my body is releasing insulin as soon as I eat, which I know is not possible. BG's do start to rise but not until about an hour after eating.
Have any other type 1's experienced similar and was any cause identified?

 

[Nicola M]

Hi @AliceBee

A couple of questions which may help people assist you with this;

What Insulin pump and CGM are you using?

What Insulin are you using?

 

[AliceBee]

Hi @AliceBee

A couple of questions which may help people assist you with this;

What Insulin pump and CGM are you using?

What Insulin are you usingmedtronic

 

[AliceBee]

Pump is Medtronic 780g with Guardian 4 sensors. Insulin is Novarapid. I have been on this pump and insulin since early 2024 which is why I didn't mention it.

 

[Nicola M]

I am on the 780g, the only time I've ever had this happen is when I am already on the low side (5.0 and lower range) and the insulin has kicked in before my food has, if I'm ever below 5 I'll usually delay giving my insulin to give the food time to hit my system but I am also on Lyumjev which kicks in quicker anyway, the only settings you can really play around with to see if it makes any difference is AIT or Carb Ratios, although I personally wouldn't do this without speaking to my diabetes team first. Tagging a couple of others who also use the 780g who may have more experience with this situation @Prancy @searley

 

[Hopeful34]

BG's do start to rise but not until about an hour after eating.

Do you go low if you don't eat till later, just wondered if your basal rate had changed? It's probably worth doing a fasting basal rate check, if you haven't already.

It depends what you're eating. If the meal contains a fair bit of fat that would slow down the absorption of carbs, eg pizza, pasta with a sauce etc.

Diabetes can cause slower transit of food in the gut, so that's another possibility. Are you going low with other meals?

 

[Tony337]

Hi
If i have been v active i often eat first them take my novorapid later otherwise i end up feeling grim.

Insulin sensitivity can strike just like resistance can but with me its activity that affects sensitivity more often than not.

50 years a type 1 who takes less insulin now than i ever have done.

Good luck

Tony

 

[T1D-USER]

I have been Type 1 for 30 years and currently on a closed loop pump. The last few weeks I have had to delay taking my bolus insulin due to bg's dropping immediately after eating and and going hypo. BG's do start to rise but not until about an hour after eating.
Have any other type 1's experienced similar and was any cause identified?

Hi Alice, I am having a similar issue, although I don’t use a pump I am using Novorapid.

I am using the libre freestyle 2 cgm to monitor my glucose and notice this same thing happens to me randomly.

I inject Novorapid, eat dinner ( almost always happens at dinner time ) and after half an hour my bg starts dropping rapidly.

I have worked out if drink apple juice 400ml it stops it very quickly and I don’t go low.
In fact it doesn’t even spike my blood sugar just stabilises it.

Like you I would love to know what causes this. The carb count is correct and a regular meal, but I suddenly need only half the insulin, but only for one meal and back to normal again.

 

[BlueBerry11]

I have had this over the last several days. Absolutely no clue why, wondering if I might be getting ill?

I was wondering if you’re still struggling with this and if you found an explanation?

 

[mentat]

Reality is a lot messier than the science might have you believe. It is possible for T1s to have a small amount of residual beta cell function that sporadically activates; it is also possible for the dopamine release caused by food to make you more insulin sensitive. Sometimes the actual reason can't be pinned down; but if you have a repeating pattern then adjust your insulin to avoid hypos even if what you're going through seems "theoretically impossible".

 

[Fairygodmother]

I’ve had this too for the past couple of weeks, despite reducing basal and delaying injecting if bs are lowing before eating.
It’s both good to know I’m not the only one and worrying to realise it’s common.
I had a very nasty incident at a friend’s when a post-prandial low led to hypoglycaemic syncope and loss of consciousness. 999 was rung but my friends were told an ambulance would be there in 2 hours!
It saps confidence when the usual jelly baby methods don’t work.
The meal we had was low in fat.
I’ve been googling, of course, and found this.

Gastrointestinal Disorders in Diabetes - Endotext - NCBI Bookshelf

 

[Fairygodmother]

Have to add that out doesn’t happen at every meal; some whole days can be perfect.