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Increased Insulin Resistance with a low carb diet?

Bebo321

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I do not have diabetes
@azure @Brunneria @tim2000s, I would be interested to hear your thoughts on an observation of increased insulin resistance with a very low carb/keto diet.

I was discussing this topic recently with somebody with T1D (we tried a food fast together over a number of days)
They noticed that coming back out of the fast, their insulin requirements had increased fairly significantly in order to manage any carb they ate (the increased requirements only lasted a few days). Interestingly, their basal had remained exactly the same throughout the fast however and blood glucose levels had remained level. This would suggest that their 'insulin resistance' hadn't actually changed at all.
What we considered had perhaps happened was that the body had become so effective at burning ketones and generating its own glucose requirements (gluconeogenesis), that once carbs were re-introduced, the body was fairly 'ambivalent' to it - after all, it had everything it needed to fuel itself perfectly well up until that point. Without cells calling out for a top up of glucose, more insulin would be required in order to be effective at taking the glucose out of the bloodstream.
This was a temporary effect and therefore perhaps different to insulin resistance created through the build up of fat deposits.

Anyway, I thought I would relay this to you (and anyone who might have their own experience to add).
Perhaps it is misleading to think of the body's adaptation to a low carb diet as becoming 'insulin resistant' and it might be better instead to think of it becoming 'fat complient'
 
It's referred to as physiological insulin resistancE and correctly so, in my opinion @Bebo321

We were discussing this on a recent thread so when I get the chance, I'll put links in for you and other readers

http://freetheanimal.com/2014/10/physiological-resistance-carbohydrate.html

http://www.marksdailyapple.com/does-eating-low-carb-cause-insulin-resistance/#comment-3087940. (Read the comment and then scroll to the top of the page for the article)

Info about the effect of fat:

http://www.joslin.org/dietary-fat-can-affect-insulin-requirements-in-type-1-diabetes.html

So, to answer your question, I believe it is insulin resistance - just with a specific cause.

It's good that the body can run on ketones when needed, but it's not something I'd be wanting to happen full time - not as a Type 1 and not if I didn't have any type of diabetes at all.
 
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@Bebo321 Yup, that's exactly my experience too. I used to cyclically Low Carb while training and my insulin requirements during my carb refeeds were about 1.5x to 2x over those two days, however, when dropping back in to low carb, it went back to what was expected.

When I've done it for a longer period, the first 2-3 days back are always heavier on the insulin. But I've always considered that "Carb resistance" rather than "Insulin resistance".

I've never experienced low carb when done for any length of time causing an increase in insulin requirements, but I've always done it alongside resistance training, which makes a significant difference to muscle insulin sensitivity, and therefore I've used it partially as a cutting technique. So I can't say that low carb in and of itself has ever caused me physiological insulin resistance.

But, and there's a big but here, what is described in the Joslin report is rather different to this effect, as it's the "Fat as accelerant" issue that's been discussed multiple times on the forum, and of its own account demonstrates the linkages that have been observed by many T1s but also in a number of studies, regarding eating fat and carbs together.
 

Thank you @azure
 
Physiological insulin resistance (PIR) is something that develops fairly gradually, after a prolonged period of ketosis, or very low carb eating (where the body is fully 'fat adapted'). Complete fat adaption is a much longer process than what is known as 'carb flu' which is usually over in a week or 3. Voleck and Phinney's experiments on tracking fat adaptation has shown it can take a couple of months or so. Sometimes longer. These studies are described in detail in 'The Art and Science of Low Carb Living', and show that athletic performance doesn't usually return to peak until a couple of months after switching to low carb (endurance athletes) and gives an indication of the length of time it takes to fully 'fat adapt'.

Now, you haven't described the details of your fast, but it really doesn't sound as if it was long enough for physiological insulin resistance to develop? If it was only a few days, then I would suggest something different. One of the giveaway signs of PIR is that baseline blood glucose levels rise a bit (fasting bgs, and the lowest number the bg falls to before the evening meal - for T2s). If that process happened to a T1 I would guess that their basal insulin requirements would rise, and you say that your T1 friend's didn't.

However, there is a thing (sorry, don't know what to call it, except to call it 'carb resistance' as Tim does). It happens to non diabetics and T2s, but I have not read about it happening to T1s, until you mentioned it today .

I can only describe it in basic terms, but when we cut the carbs very low, our body stops producing as much insulin for meals (obviously), and it gets used to this state. Like being on holiday from carbs. It kicks back, chills out, and doesn't stay on carb-alert. Then, if we re-introduce those carbs, we tend to get higher blood glucose reactions to the food until our body 'wakes up' and starts to react quickly. It usually takes a few days, at which point everything goes back to how it was before the low carbing. I suppose you could describe it as the carb tolerance resetting, but that is a very clumsy description.

I've also read it described as 'downgrading of enzymes' and 'the pancreas getting lazy', and several other things. Followed by a reversal of the process once the carbs are reintroduced. And to be honest I have never read up on it, mainly because I happily avoid big doses of carbs, so don't have much personal interest. I don't even know what the official name for the process is. I am sure that @tim2000s does It certainly isn't specific to people with diabetes since it is well documented in non-diabetics. And it is the reason why people should eat 'standard' amounts of carbs before having the glucose tolerance test, because if they have been low carbing beforehand, they will probably get a delayed or inadequate response to the glucose, have a higher spike and throw out a false positive on the test.

Up until now, I have kind of assumed that it wouldn't happen to T1s, because of the loss of their beta cells, and the injected insulin - but you seem to be describing exactly this process - so maybe it DOES happen to T1s too? If so, then the process is obviously a lot more complex than just the pancreas getting a bit lazy at insulin production if it isn't constantly exposed to carbs...
 
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Yes, good point about the number of days the fast is undertaken. I've only ever been on unchosen fasts due to illness, and I haven't noticed any PIR when I return to my normal,diet. So that does suggest it takes a while to build up.
 
This is a subject that has been discussed regularly over the years ive been a member, even argued about quite heatedly at times but there is evidence to back up your statement, whether or not you chose to believe or reject it is entirely your decision.

After reading posts here, research papers and books on the subject I came to the conclusion shortly after my diagnosis that it was better for me to lose weight and with it my insulin resistance with a low carb/low calorie diet than just to control my bg levels with a low carb/high fat diet, I'm glad I did as it worked for me and since losing weight and my insulin resistance I can now eat pretty much what I want to and have had great HbA1's for the last 7 plus years, plus I feel much better for the weight loss.
 
Brunneria said:
I am sure that @tim2000s does
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I may have to do some digging. I've not seen any names...
Brunneria said:
If so, then the process is obviously a lot more complex than just the pancreas getting a bit lazy at insulin production if it isn't constantly exposed to carbs...
Click to expand...
I think this is linked to the activation of GLUT-4 receptors. We know that both exercise and insulin "activate" GLUT-4 although it seems that there are different pools for different activation mechanisms, muscle contraction and insulin.

Studies done on GLUT-4 suggest that in humans there is a model in which GLUT4 is present in a storage compartment, from where it is released in a graded or quantal manner upon insulin stimulation and in which released GLUT4 continuously cycles between intracellular compartments and the cell surface independently of the nonreleased pool. Hypothetically, it could be that after a period of low carb, and therefore low insulin, the insulin required to unlock the required quanta of GLUT-4 is much greater than under normal glucose metabolism conditions. Almost like a hibernation.

I'm struggling to find any research on the anti-hypothesis for GLUT-4 activation though, so this is an interpretation of what I've read in relation to GLUT-4 ACtivation.
 
@azure I've been hitting the VLC pretty hard the last couple of weeks and now starting to see rises from relatively small amounts of carb that take more insulin than expected to bring back down.

The daily apple link was interesting and in particular the statement that 10% of calories should be carbs. So essentially low carb for a T1 should be to keep within that range of 60 to 130 carbs to keep out of ketosis (and associated insulin resistance) whilst also keeping BG manageable.

I got 60 grams from 10% of 2500 cals/day and 4 cals per g of carb if anyone wonders.
 
Thank you for all of your input - it's fascinating stuff!
I think my confusion is rooted in the definition of exactly what insulin resistance is. If you would please bear with me....

Version 1.
To my basic understanding (and I bow to your greater knowledge on this) it has to do with a 'faulty' signalling pathway for the GLUT4 receptors, meaning that they no longer translocate effectively through insulin stimulation. (Interestingly this process of translocation is maintained perfectly well in the case of muscle contraction which is why exercise is so useful as a means of managing BGs). I understood that this diminishing sensitivity to insulin takes a long time to develop (months certainly, more likely years) and was linked to excessive fat deposits throughout the body - most particularly liver and muscles.
I considered that this was what was commonly being referred to as the insulin resistance connected with the development of type 2 diabetes.

Version 2.
During a period of low carbing where the body becomes Keto adapted, I think there is every possibility that 'carb resistance' becomes a factor (described very beautifully @Brunneria with the pancreas's 'holiday from carbs'. The other thing you mention @tim2000s is in relation to GLUT4s and another thought occurs to me - bearing in mind that GLUT4s are able to proliferate in number remarkably quickly through exercise, I wonder if it isn't just that the opposite happens when we stop eating carbs - GLUT4 receptor numbers diminish. Perhaps it would take two or three carb meals for numbers to bump back up again where they would normally be on a 'standard' diet. Both pancreas holiday and lower GLUT4 numbers would explain a period of apparent insulin resistance after a period of low carbing.

Version 3.
This relates to the liver and its habit of releasing glucose in response to cortisol. Theoretically if the liver is churning out glucose first thing in the morning (or if somebody suffers with chronically high stress levels), then even with reasonable insulin sensitivity, with the best will in the world elevated blood glucose levels may be the result. The 'faulty' cortisol/glucagon signalling - is this effectively 'insulin resistance'? Take a finger prick test and it would appear so, but it has a completely different meaning.

Version 4.
This one relates to eating (and thank you @azure for your links). The Joslin item is of interest in relation to this as it relates to the insulin resistance induced though consuming fat in combination with carb (I appreciate the Joslin trial included protein too). I found one bit of research where triglycerides were infused into the bloodstream of an athlete during digestion and there was a marked reduction in insulin sensitivity.
I have to say, this is the version of 'insulin resistance' that has me stumped as to the scientific explanation (or just a logical hypothesis) and would be interested to hear your thoughts.

I think I understand what you mean by you description of 'Physiological Insulin Resistance' @Brunnaria - thank you.
Otherwise, is there anything I've missed or misunderstood regarding what we might refer to everyday insulin resistance?

(Oh, sorry, the fast was over five days, followed by two days low carb 500 calories per day - I chickened out after four days)
 
Bebo321 said:
I have to say, this is the version of 'insulin resistance' that has me stumped as to the scientific explanation (or just a logical hypothesis) and would be interested to hear your thoughts.
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I'm going to pin @Oldvatr on this one as I recall he had linked to some research that went in to why fats seemed to cause an increase in insulin needs.

From what I recall though it's kind of a 3a function, in that higher fat content in meals gets converted to free fatty acids that encourage the liver to release glucose from it's glycogen stores, hence creating a double bounce on the high fat/high carb foodstuffs.
 
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Not sure if this is the one, but its amusing anyway.
http://chrismasterjohnphd.com/2012/01/07/we-really-can-make-glucose-from-fatty/
Think I had a different one that showed how IR is increased for T1D and triggered by high fat intake, This, the Pizza effect, is a different beastie. Will try to dig it out again, but I did not bookmark it since I am T2, so it did not apply to me so much.

Try this one, it looks familiar:

http://www.joslin.org/dietary-fat-can-affect-insulin-requirements-in-type-1-diabetes.html
 

I can only give my own opinion but I personally agree that there may be a minimal level of carbs that are appropriate for Type 1s. For that reason, I would never go VLC. There are a number of other reasons too, but I won't bore you : D I'd go for a higher percentage than 10% but that's just my unqualified opinion. Not a huge amount, but slightly higher. I think Mark (Daily Apple) has a more sensible approach to carbs than others. Somewhere he has a 'carb graph' showing amounts for (non diabetic) people depending on whether they have weight to lose, etc.

I eat 180g carbs a day currently. I can't foresee a situation when I'd eat below approx 80 or so.

I'd also add that for Type 1s in particular circumstances eg pregnancy, breastfeeding, etc carbs are very important.
 
Bebo321 said:
Thank you for all of your input - it's fascinating stuff!
I think my confusion is rooted in the definition of exactly what insulin resistance is. If you would please bear with me....
Click to expand...

You lost me half way through version 1.

All I know is that insulin resistance causes raised bg levels, and if fat can cause IR then I don't want to add extra fat to my diet, as for the whys and wherefores I'll leave that to the scientists.
 
Sid Bonkers said:
You lost me half way through version 1.

All I know is that insulin resistance causes raised bg levels, and if fat can cause IR then I don't want to add extra fat to my diet, as for the whys and wherefores I'll leave that to the scientists.
Click to expand...
As I understand it, this thread is describing an effect that so far has only been noted in T1D. It does not seem to apply to T2D.
For T1D I think it is an effect on the Liver, whereas for T2D the IR is mainly muscular. So T1D tend to lose weight before diagnosis, T2D suffer metabolic syndrome. Either way IR gives high bgl, But the high fat has been shown to only affect T1D in this manner. For T2D, it just seems to delay the carb bump after a Pizza.
 
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