Leaving Ketosis - Insulin Sensitivity Loss?

[Hoping4Cure]

This is a spillover question from the fasting mimicking diet thread.

After about ten cycles of FMD last year I came to the conclusion that either fasting is what destroys insulin sensitivity in type 1 diabetics, or leaving ketosis and re-entering a more sugar heavy diet briefly.

This goes against what is expected, namely that extended fasting periods should increase insulin sensitivity, at least in type 2 diabetes.

I'm just wondering if there are any type 1s on ketogenic diets who might periodically "cheat" and eat carbs, and thus leave ketosis temporarily, to what extent their insulin sensitivity (or carb tolerance, same thing) is impaired when they do so, compared to when they are on a consistently non-ketogenic diet.

I noticed this several times. When I'm eating more or less a low-ish carb diet, then suddenly binge on something, like a curry with rice or naan bread, that my insulin requirements are far, far less than if I'm fasting all week, then eat the same exact meal. Even up to a week later, my sugars will be much higher than normal, if I consume *any carbs*. I once had to take 200 units of insulin to bring me down after a feast.

Has anyone, of either type 1 or type 2, experienced this? I'll ask in the fasting forum as well, but I figure I keto subforum goes might know the answer.

 

[DCUKMod]

This is a spillover question from the fasting mimicking diet thread.

After about ten cycles of FMD last year I came to the conclusion that either fasting is what destroys insulin sensitivity in type 1 diabetics, or leaving ketosis and re-entering a more sugar heavy diet briefly.

This goes against what is expected, namely that extended fasting periods should increase insulin sensitivity, at least in type 2 diabetes.

I'm just wondering if there are any type 1s on ketogenic diets who might periodically "cheat" and eat carbs, and thus leave ketosis temporarily, to what extent their insulin sensitivity (or carb tolerance, same thing) is impaired when they do so, compared to when they are on a consistently non-ketogenic diet.

I noticed this several times. When I'm eating more or less a low-ish carb diet, then suddenly binge on something, like a curry with rice or naan bread, that my insulin requirements are far, far less than if I'm fasting all week, then eat the same exact meal. Even up to a week later, my sugars will be much higher than normal, if I consume *any carbs*. I once had to take 200 units of insulin to bring me down after a feast.

Has anyone, of either type 1 or type 2, experienced this? I'll ask in the fasting forum as well, but I figure I keto subforum goes might know the answer.

Hoping4Cure - You might be interested to google "last meal effect".

Our bodies like to run to patterns, and will do what they can to keep us there. An example of this is where sometimes T2s (I'll stick with T2 as that's where my personal experience lies) make a tweak to their diet, say, but it takes longer than expected to show through in their blood sugar levels. In other words, their liverer keeps pumping out glucose to bolster the blood sugars into the previous "running range".

I found as my journey progressed, my blood sugars would notch down, then stabilise, then notch down again - most odd.

On experimenting (aas we all do), with something carbier, I could see a bit of an unexpected, seemingly excessive, rise to my numbers, but if I repeated the experiment the numbers would be more aligned to what I had been expecting.

In essence, my body would be caught off guard by the carb hot, and my system wasn't prodcing the most appropriate mix of digestive juices to metabolise it efficiently. Whilst our main interest is in the insulin (and insulin sensitivity), there are other hormones and enzymes in play when dealing with all that scrumptiousness.

That's probably waaaaaaaay to simplified, but describes my personal findings.

 

[Hoping4Cure]

Ya I think you're right about the other non-insulin aspects of metabolism being involved. I mean, on those fasting weeks, I barely move or do anything at all, so suddenly I'm eating this big meal and the muscles have no real need or use for it.

I also mis-spoke in my post, I meant to say I expected my insulin resistance to go down but it went up, significantly, after a week of fasting. Dr Longo's literature on the topic says that long-term, insulin resistance should go down, in type 2s at least. I'm just trying to get to the bottom of why insulin wouldn't work as well. Maybe my muscles atrophied during the weeks I was fasting?

It was so bad, I thought my insulin had gone bad or something. Scary actually.

In the future I think I'll just try to stick to ketogenic all the time, and for re-feeding just avoid carbs like the plague. It's not that easy though, especially if you like to have a drink. I think I'll stick to red wine as much as possible, only 2.7g of carbs per glass which is fine.

 

[brassyblonde900]

Fasting is not for everybody.
The amount of Glycogen my liver was pumping on extended fasts was frightening.
With a heavy heart, I came to the conclusion that fasting is not for me.
It would be ironic to get complications because my BG was very high due to fasting, and or exercise during those fasts.

 

[AloeSvea]

How many days are your extended fasts, @brassyblonde900? from my own experience, is that after a certain amount of days my blood glucose comes down, and my liver stops churning out the glucose too (as - glycogen is it? depleted and no food to replace it). For me, after years of keto, and periods of no-food fasting, it is three days, and it is practically spot on every time, which coincides with the ketone levels showing up pink and purple on (my cheapo method on a budget!) ketostix. ie no glucose for me to burn via liver, fat burning kicks in. Soon after diagnosis some four years ago, and not on low carb/keto, the changeover to normal BGs was a lot quicker. What I like about any kind of no-food regime (or very low amount of food, ie fasting/going hungry/semi starving lol) is that the normal-er BGs hang around for at least several days after.

 

[brassyblonde900]

How many days are your extended fasts, @brassyblonde900? from my own experience, is that after a certain amount of days my blood glucose comes down, and my liver stops churning out the glucose too (as - glycogen is it? depleted and no food to replace it). For me, after years of keto, and periods of no-food fasting, it is three days, and it is practically spot on every time, which coincides with the ketone levels showing up pink and purple on (my cheapo method on a budget!) ketostix. ie no glucose for me to burn via liver, fat burning kicks in. Soon after diagnosis some four years ago, and not on low carb/keto, the changeover to normal BGs was a lot quicker. What I like about any kind of no-food regime (or very low amount of food, ie fasting/going hungry/semi starving lol) is that the normal-er BGs hang around for at least several days after.

Only just seeing this, sorry for my late reply.
When I was doing extended fasts, I did 4-5 day water only fasts. I also did HIIT, I'm sure that did not help with the gluconeogenesis either.

My BG especially post exercise at one point was as high as 8.5, which scared me.
I reckoned If I'm going to be that high, for whatever reason, at least, let it be from some decadent indulgence, most certainly not from doing what I believed was the right thing to do, so I could stay healthy and complication free.

 

[AloeSvea]

First of all - I am well impressed that you can do HIIT while not eating for 4-5 days - kudos to you!

Understood re the 8.5 scare. At least you know that the physical exercise is the thing doing the most against one of the big 'complications' killers of type twos - cardiovascular disease. Decadent indulgences have their place in a longterm plan (I would argue!) but alas, more about keeping our mood buoyant , rather than helping us stay healthy and complication free.

I don't know what to make of physical reactions to fasting and exercise either, for we type twos. Dr Fung believes that it is glucose in the body, not just glucose in the blood, that we should be considering regarding our health, and I try to keep that in mind when contemplating what to do about my own insulin resistance and blood glucose levels. And if I have understood him rightly - depleting the body of the glycogen stores is good for our health.

And as for us creating our own glucose and churning it out in great unhealthy bulk (my big problem too) - I do not know what to think. For myself, I see that the insulin levels/gluconeogenesis signaling must be so completely shot is why this happens to the extent it does. Type two, for sure. Will they right themselves? Only time will tell, otherwise, I need to accept I may have permanent damage in this regard, and therefore, lifelong too-high BG levels, and therefore too early death. But mostly - I am optimistic. Nicer to go through life with optimism rather than the opposite in any case! Regardless of the physical reality.

 

[tim2000s]

@Hoping4Cure - missed this thread originally. What you describe about coming out of keto is a widely observed phenomenon. From what I understand, when you're Keto adapted, part of that process is to reduce the availability of insulin receptors in the musculature in order to retain whatever glucose is produce by the body for use in the brain (the old 30g point).

When you then eat carbs, due to the majority of insulin being used in the musculature rather than the Liver, where it would normally have an effect in a non-T1D, you require additional insulin to kick the muscles into using the carbs, effectively seeing significant insulin resistance. It usually doesn't last more than a couple of days. I'd imagine you'd have the same effect when fasting.

 

[ringi]

This has been seen in a few people without diabetes with their fasting BG increase a little when they keep to a 100‰ beef diet.