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Carb cycle issues

D

Donczz

Member
Messages
7
Type of diabetes
Type 1
Treatment type
Insulin
Hi everyone!
I was wondering if somebody experienced any problem with a carb cycling diet.
Due to my protocol I followed 5 days of low carb (between 50g and 100g daily) with a light daily calorie deficit. Then the sixth day I dropped fat and protein intake and ate high carbs mostly from fruit.
The problem is that even if insulin carbs ratio is the same my BG dropped during fasting periods between meals and to maintain it I needed to eat like 20/25g of carbs each hour. I have already experienced something like this when the intensity of my physical activity increased, but in this case I haven't increased it and also my basal insulin intake remained stable for the last 2 months.
Can somebody give me some explanation?
Is it due to the change in carbs/protein intake?
Is it possible that it has been affected the release of glucose from the liver? If yes why?

Thanks in advance guys!
 
I'll start by saying that I'm not overly surprised that you're having issues. As a T1, routine and consistency seems to be critical for the majority of other T1's I've spoken with. The fundamental constant, in my opinion, for stable BG's is a regular and steady daily carb intake. It may be 50g or 500g, but I've always found difficulties if I've suddenly changed this value.

The DIA of most rapid insulin is 3-5 hours, so even in your fasting periods, you may well have active insulin on-board. If you've taken too much insulin (ie, not factored in your IOB) then you could see drops between meals. Exactly when these drops happen - is usually an individual thing, and does depend on what you've eaten and when. If you're eating more than 3 times per day, insulin stacking can happen and that may be a reason for your BG's dropping between meals.

Also, even if you think your ICR's are set correctly, the higher your carb intake - the larger your error margin can become. For instance, if you ate 100g of carbs and used an ICR of 1:10, when in fact you are 1:12 - that would be 1.6u extra insulin administered. 1.6u can drop BG by as much, and possibly even more than 5mmol/L. So as you can see, hypos are easily encountered when I:C ratios aren't quite right.

Have you tested for ketones on your 50g carb days? If you're in dietary ketosis during these days, then when you swap to high carb days, your liver may rob a lot of the glucose from your blood stream to replenish glycogen stores. It's a possibility.

Apologies for the long winded reply, but as you can appreciate - there are loads of reasons why you may be experiencing these hypos when reintroducing carbs.
 
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how long do u cycle for?
 

Thank you very much for your reply.
Unfortunately I have not tested my ketones.
About the ICR error I think it could be but just partially, because If I had to consider the error of my ICR it would have been changed from 1:6 to 1:12 and in that case I would have experienced some hypos also in other days during meals I've ate something like 40g of carbs. In addition I have to say that my BG decreased until 3am and my last fast acting insulin injection (humalog) was at 4pm, it is a lot more than 5 hours.

I don't know if it is a silly question, but can the liver take glucose to replenish glycogen even if I don't have insulin on board except the long acting one?
 
Donczz said:
In addition I have to say that my BG decreased until 3am and my last fast acting insulin injection (humalog) was at 4pm, it is a lot more than 5 hours.
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Then I'd look at reducing my basal dose. Basal doses and rates aren't static for everybody and can change when carb intake is varied.
Donczz said:
I don't know if it is a silly question, but can the liver take glucose to replenish glycogen even if I don't have insulin on board except the long acting one?
Click to expand...
No silly questions here, only silly answers

I think the answer to that question is yes; but I'm no biologist or doctor. Basal insulin is virtually the same as bolus insulin; it's just the rate it is released that differs. That's certainly the case with Novorapid and Levemir. So it would certainly have that ability. That's also why basal can cause hypos, because too high a dose removes too much glucose from the bloodstream and stores it in the liver and muscles. Once your liver and muscles are full to the brim, glucose is stored as fat.
 
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I think I'll understand better everything decreasing the basal and seeing what happens repeating an high carbs day. Although I think could be worthless, probably I'll experience higher fasting BG levels during low carb days.
 
Donczz said:
I think I'll understand better everything decreasing the basal and seeing what happens repeating an high carbs day. Although I think could be worthless, probably I'll experience higher fasting BG levels during low carb days.
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Apologies; I edited my post to try and explain a little better. But I was too slow and hadn't finished before you quoted it

What's this carb cycling thing all about anyway?
 
Donczz said:
Sorry I don't get your question
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I think there has been a little confusion between the activity cycling (bicycle) and what's getting discussed on this thread
 
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GrantGam said:
Apologies; I edited my post to try and explain a little better. But I was too slow and hadn't finished before you quoted it

What's this carb cycling thing all about anyway?
Click to expand...

No worries
Yes probably it was because of the too high basal , I'll be able to confirm this in the next few days.

Carbs cycle diets meant to lose body fat while maintaining or even increasing muscle mass.
Essentially one can choose the macros percentages and then maintain everyday the same amount of protein and fat. The days differences are based on calories deficit days and maintenance/surplus days.
The important thing is that there is an overall weekly calorie deficit.
 
Thanks for the clarification.

I'll tag @TorqPenderloin who is a T1 weightlifter and will likely give you sound advice regarding dropping weight but keeping muscle mass.
 
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