'Aha' moment about fat

[linda321]

I had some peculiar readings/graphs on my libre last night. I have a new sensor, just 48 hours ago, so it could be because the sensor hasn't settled down yet. However, this is my 5th sensor and all the others have been accurate right from day 1.

Anyway, here's what happened. I had a 9 bar before going to the gym, which raised my BS quite a bit. Ended up starting my hour at the gym a bit too high really, but came down by about 1mmol by the end of the session. I injected 8u Humalog when I got home, and ate dinner of stir fry, prawns, 100g noodles, in total 39g carbs. I also had a handful of blueberries with a generous 2 spoonfuls of full fat creme fraiche. During the evening I had a handful of nuts and a glass of wine.

By 10pm, my libre read that I had come down to 9.4. I decided not to do a correction dose. The libre shows that during the night from about midnight until 3am, my blood sugar was hovering around the 15mmol level! It came back down in a more or less straight line to about 9mmol!

Could this be the amount of fat in the creme fraiche and nuts? Both high in fat! I bolus for protein (half) but not for fat. I know that fat can increase BS hours after eating.

Lately my BS has been quite good, and I have been eating half-fat creme fraiche, and avoiding eating in the evenings after dinner. Maybe this is why I have been having such trouble controlling my blood sugar? I'm going to avoid the high fat (although I LOVE it!) and eating in the evenings and see how it goes.

 

[tim2000s]

Fat on its own doesn't get converted to very much glucose. It is usually considered to be at a rate of around 10%. As a result, it's unlikely to be the fat causing a rise on its own. The amount in two tablespoons that might convert would be around 1 or 2 grams. You also mentioned nuts. Nuts contain both Carbs and Protein and others have mentioned how some nuts cause their glucose levels to increase. I'd be inclined to look at these as the culprit of a rise, rather than anything else. Do you know what weight you ate and what sort of nuts?

What fat does do is slow down the digestion and absorption of any carbohydrates, which is more likely in this case. What you haven't mentioned is your pre-dinner blood glucose level.

I'd also ask questions about your IC ratio and your background insulin. If your blood glucose level dropped from 15 to 9 in 4 or 5 hours, only using your basal insulin, your basal insulin is very much not at the right level. I saw a similar thing the other night after the gym, where my levemir straight-lined me from 8 to 3 over five hours. It was very disconcerting as I'd already reduced the dose to my post gym dose.

Sorry @linda321 , but I really don't think it's fat in the Creme Fraiche or nuts on their own. I think there is also something going on with your insulins.

 

[linda321]

Forgot to say, Yes my basal is correct! I have done quite a bit of overnight basal testing, and usually have flat graph overnight now.

Edited to say:

Sorry @tim2000s , I posted this before I saw your reply!
I think my basal is correct, as above. I injected 8u of rapid acting after the gym to cover my 39g of carbs (including half the protein in the prawns) and a correction dose - hence the fast decline from post gym BS of 16mmol, to 9mmol before bedtime. Pre gym level was 14.7, actually it went up at the gym to 16.4.