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Low carb - but high sugars - advice please!

Odin004

Well-Known Member
Messages
165
Type of diabetes
Type 1
Treatment type
Insulin
Hi all,

I wonder if I could get your thoughts. I'm T1, and had a bad hypo last year - following this I decided to go on a low carb diet, to limit the amount of insulin in my system at any one time. I'm much happier doing this, and can't now imagine going back to a high carb diet.

I made the transition to low carb fairly slowly, and I did lose about 8kg in body weight (possibly as I wasn't really replacing the lost carb calories with protein/fat) - however, for the last 4/5 months, my average daily carb intake has been about 45-65g, and my weight loss seems to have now plateaued, as it's been fairly constant over this time.

The low carb diet has certainly help control my sugar levels, with far less swing in the highs and lows, and generally confined to a narrower range - however, in the last month or so, I've found that I need much more insulin than normal, to maintain sugars in a good range. My long-standing ratio of 1u/10g carb just isn't working (by a long way), and sugars are frequently in the 12-15 range. Even if I take a 3 unit correction dose, the sugars might only reduce by say 2 or 3 mmol. This is very unusual for me - having been diabetic for around 15 years, I'm of course familiar with all the different factors that can cause insulin resistance or sensitivity, and clearly there are periods where you're going to be more or less sensitive than usual - but as my sugars have been high for around a month, I have to say I'm quite confused by this.

I contacted my specialist diabetic dietician, who tells me that this is apparently a known issue with low carb diets - she tells me that people do quite often need to up their ratios when they switch to low carb - however, she doesn't know why this is the case.

I've ruled out all the usual suspects (illness, stress, activity levels, dodgy insulin pen etc) - and as I say, it's only been an issue in the last month or so - my low carb diet was fine for months prior to that. Also, it's frustrating, as the reason I switched to low carb, was to actually reduce the amount of insulin I need - which seems pointless if I need to significantly increase my ratios anway!

Any thoughts would be most welcome.
 
@Odin004 If you drop your carbs too low, you can get insulin resistance. That's one of the reasons I don't eat very low carb.

It sounds like this could be what's happened to you.

It's a myth that every T1 on VLC can reduce their insulin. Many end up bolusing as much for a no carb meal as they would for carbs.

If you've ruled out all the usual suspects for high sugars, then this might be the cause.
 

Hi Azure - thanks for your reply - yes, that does seem likely; can I ask, do you know why low carb diets might cause insulin resistance? It's confusing, as there's been no change to my diet in about 5 months, yet this issue only arose in the last month or so. Also, I thought that 45g-65g carb was only "moderately" low rather than "very" low - I know some people prefer less than 20g carb per day; however, I suppose everyone will react differently.
 
Yes, your 45-65g isnt xtremely low, but, as you say, your 'sweet spot' for carbs may be different than another person's.

I don't know precisely why the IR happens, but I believe it's to do with the fact that Type 1s have little/no insulin so VLC doesn't work for us in the same way that it might work for Type 2s who have adequate or even extra insulin production. Our metabolism reacts differently. In addition, the higher level of fat can impact blood sugar. Added to that, I believe the body can see the lack of carbs as 'starvation' so induces IR.

If you've ruled out the obvious things like dodgy insulin, infection, etc,,etc, then perhaps you could try upping your carbs ever so slightly across the day and see if that helps get back your sensitivity.
 

Thank you @azure, that does make sense - I will try that and see what happens!
 
Sometimes when a diet becomes too tight, it can stress the body and provoke glucose production from the liver. I am not 100% sure on this one, so a professional opinion is advisable. Better safe than sorry.
 
The other thing to consider @Odin004 is are you blousing for protein? If you're eating a meal with minimal carbs your body is going to want to get its energy from somewhere and it will do that by performing gluconogenisus on protein, turning the protein into glucose. If you've been low carb for 6+ months it might jus be that your body is getting more effective at gluconogenisis. This is still a process that takes a while, so might explain the lack of impact of correction doses: if you're delivering a correction dose 2-3 hrs after a meal just as protein starts to kick in to raise blood sugar then the correction dose will be dealing with the protein rather than correcting.
 
I agree with @catapillar. I'm ultra low carb, ulta low insulin doses but I do need to bolus for protein. I gluconeogenesis very quickly.
I eat four small meals a day about every three hours. This keeps me steady. I'm not sure if I'm just running out of insulin then ( I take 1-2 lantus so it's gone by morning or at least not noticeable) or if it's picking up the tail end of the protein though I don't eat large quantities of protein.
I also take a small bolus an hour after bf to stop/ avoid the morning rise. So 6 small injections a day but no peaks and troughs
 


Thank you @catapillar , that also sounds quite possible - historically, I've never needed to bolus for protein, but perhaps things have changed due to the low carb diet - your explanation also makes sense of the fact that my sugars have only crept up over the last month, with no change to diet from the preceding months. Perhaps if I were to add a little extra carb (as @azure says), my body's need to convert protein to glucose may also diminish - and therefore, my ratios may normalise. I will see what happens.
 
Agree with both Azure and Catapillar's points.

@Odin004 , I know some type 1's who follow a VLC diet have had to start taking the drug Metformin to help with IR, perhaps you should ask your Dr or Consultant to prescribe it to see if it helps matters.

Good luck and hope you get things sorted.
 
There was a study published recently that showed that meals containing high fat content can acutally increase IR in T1D.

Its known colloquially as the Pizza Effect.
 
Thanks @noblehead

From the replies on this thread from @azure, @catapillar and @leslie10152, it seems that very low carb diets can:

- causes insulin resistance;

- cause the liver to produce more glucose;

- cause the body to convert protein to glucose.

@Oldvatr also mentions that high fat diets can increase insulin resistance - and on a LCHF diet, of course, fat is higher.

It seems to me that in each of the above cases (and I'm sure there's a complex overlap between all of them), the situation should, in theory, be reversed by introducing a little extra carb - perhaps I've gone too low carb for my body's comfort. Conversely, it also seems to me that increasing insulin/carb ratios to compensate, would theoretically be quite detrimental - as taking more insulin can surely only exacerbate each of the above issues, leading to a vicious circle.

I'm quite confident I'll never go back to a high carb diet - I think my goal should be to have just enough carb to avoid any of the above issues; if I've gone too low with the carbs, then hopefully by adding some carb, I can reverse the situation. I'd rather try to deal with it by dietary changes before thinking about medication, although I appreciate that's not possible for everyone.

Just food for thought - I recently had two glasses of wine while out with friends during the day; this was over a 5 hour period. I'm aware that alcohol inhibits the liver in releasing glucose, meaning that your basal insulin will effectively be higher than needed, and of course, this can lead to hypos; however, I was quite surprised by the extent to which my sugars fell later that evening (they didn't go low, but they dropped sharply). I took 20g carbs (from Lucozade) - which raised my sugars as expected - but they then came back down to where they were before an hour or so later; I then took another 20g carbs, again from Lucozade - and exactly the same thing happened. I hadn't bolused for some hours prior to the first drop. I attach a screenshot of my Dexcom G5 (relevant peaks circled in red) - I wonder whether the fact that my sugars fell so sharply after the wine lends some support to @leslie10152's suggestion that my liver is now regularly producing more glucose than normal as a result of the low carb diet - as when the liver was temporarily compromised, the basal insulin acted quite powerfully.

 
I am a T2D on orals, so my Insulin Resistance is different to yours. However we may both be suffering Liver Dump as explained earlier. However, with a low carb diet, this periodic dumping may actually help reduce IR. and anyway will lessen as the liver stores become depleted by the dumps. That is, Provided you continue to keep the carbs low. The liver is like a rechargeable battery that gets charged up when there is more blood glucose than needed for activity, This is why inulin is needed, for storage purposes. So upping the carbs as you suggest will keep the liver charged up, I believe.

Many of us here use imtermittent fasting to help reduce IR (but that may only be for T2D, so may not be helpful for you) the idea behind fasting is that it forces the liver to dump lipid fat for burning via ketosis, but for this to happrn you carbs MUST be kept low.
 

I have never heard that low carbs increases insulin resilience. Where could I find more data on that please?
I knew that high carbs caused insulin resilience.
 


Thank you, that's is quite interesting - in that case, perhaps a low carb diet - with the occasional "moderate" carb day, could be an idea!
 
Carbs and saturated fats make me insulin resistant. I'm in ketosis at all times and keep my glycogen stores quite empty. If I over eat carbs or protein I require more insulin for a few days even after just one meal.
 
For instance if I eat a 1/4 ln burger and some veggies in one sitting I require at least two split boluses and will always have a higher fasting for about three days. I keep my protein moderate and eat a high fat diet. Mostly consisting of avocado, fatty fish, olive oil, mayo, whatever fat comes with my protein ( like egg yolk and mayo or chicken thighs sans the skin) a bit of cheese and a variey of nuts.
I can't comment on carbs as I simply don't eat them.
 
Fleegle said:
I have never heard that low carbs increases insulin resilience. Where could I find more data on that please?
I knew that high carbs caused insulin resilience.
Click to expand...


Hi @Fleegle - I also didn't know that either, until today - my dietician tells me that low carb diabetics often need to increase their carb/insulin ratio - but didn't know why this is. Following @azure's comments above, I've done some googling, and although it's too early in my research for me to recommend a reliable source of information (as is often the way with the internet!) I can see that it's certainly a "known" issue. It appears that insulin resistance can happen when carbs are very low - but what constitutes "very" low seems to vary from person to person. Also, it may well be different between T1s and T2s.
 

Hi Kristin - it seems that your body has well adjusted to your diet - can I ask, what would a normal ketone reading be for you?
 
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