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Intermittent fasting

Dudette1

Dudette1

Well-Known Member
Hi guys,
I did a bit of fasting when I was told I was type 2..
However now been told I’m type 1 I was just wondering if anyone does fasting!
I have some weight to lose and didn’t mind the eating regime.
Thought on this please and if it works for type 1s on insulin
 
Hi @Dudette1 I regularly don’t eat beyond 3pm til my breakfast the following morning. 6-8am depending on when I wake. Haven’t had a problem with it. I am retired and cook main meal between 1-3 and never feel a need to eat later. I know I have no food/insulin on board at bedtime which helps with my control. I always swim early morning before breakfast too.
 
Provided you adjust the insulin to suit you should be OK. While you obviously don't bolus for a meal you don't eat I also find after a day or two the basal insulin requirement starts to fall.
 
Thanks for the responses guys
I’ve set my fasting to start from 3pm and not to eat till 9am in the morning..
i take tresiba in a morning and fast acting nova rapid when I eat so hoping this will work well for me.
 
I'm incredibly new to this, and heed the advice of others who've lived with t1 diabetes more than what I'll say. But, I'd be conscious of checking ketones to begin with. As far as I know, you can encourage ketogenesis by fasting, increasing the risk of dka. It may be best to speak with your diabetes team about this they'll provide better, tailored advice to your situation.
 
I’ve checked my ketones,
I went into dka in august last year with normal levels so I’m very cautious about them this time.
Thanks
 
SherwoodT1 said:
I'm incredibly new to this, and heed the advice of others who've lived with t1 diabetes more than what I'll say. But, I'd be conscious of checking ketones to begin with. As far as I know, you can encourage ketogenesis by fasting, increasing the risk of dka. It may be best to speak with your diabetes team about this they'll provide better, tailored advice to your situation.
Click to expand...
There‘s a big difference between diabetic ketoacidosis and nutritional ketosis:

Nutritional ketosis vs diabetic ketoacidosis (DKA) - Diabetes

To begin Diabetes Awareness Month, we wanted to make the important distinction between nutritional ketosis and diabetic ketoacidosis (DKA).
www.diabetes.co.uk www.diabetes.co.uk
 
Great link
I had euglycemic ketoacidosis and it was an absolutely horrible experience.
I don’t think many people know about it.
A man on here told me I wasn’t in DKA because my levels were normal.
I showed him the doctors letter and said yes I was.
This site is brilliant for educating us all
 
Goonergal said:
There‘s a big difference between diabetic ketoacidosis and nutritional ketosis:

Nutritional ketosis vs diabetic ketoacidosis (DKA) - Diabetes

To begin Diabetes Awareness Month, we wanted to make the important distinction between nutritional ketosis and diabetic ketoacidosis (DKA).
www.diabetes.co.uk www.diabetes.co.uk
Click to expand...
Thanks for the link, it's really informative! I would assume though that when ill, fasting on a low carb diet would put you at greater risk of dka? Assuming the illness is making your glucose levels haywire.
 
SherwoodT1 said:
Thanks for the link, it's really informative! I would assume though that when ill, fasting on a low carb diet would put you at greater risk of dka? Assuming the illness is making your glucose levels haywire.
Click to expand...
According to Dr Bernstein the real problem is dehydration.
Some medications can result in euglycemic ketoacidosis - but I don't believe insulin is one of them. Measuring ketones as well as blood glucose should help identify these cases.
Unfortunately if you are very low carb to start with you are on your own ... ketones are unlikely to match those expected by the general medical profession :(
 
Dudette1 said:
Great link
I had euglycemic ketoacidosis and it was an absolutely horrible experience.
I don’t think many people know about it.
A man on here told me I wasn’t in DKA because my levels were normal.
I showed him the doctors letter and said yes I was.
This site is brilliant for educating us all
Click to expand...
@Dudette1

This came up at my last review. I try to be mostly low carb. My endocrinologist has been running a research trial of low carb/keto eating Type 1s. I had mentioned that my blood ketones could sometimes be quite high even with normal BGs. This led to an interesting discussion of how do I know that as a Type 1 that I'm just in nutritional ketosis and not euglycemic DKA? I said I went by symptoms (I've had several very unpleasant DKA experiences) - but he's still evaluating to see if recommending low carb/keto to Type 1s is safe, and asked me to more regularly check my ketones, especially in the morning when they can be highest. Info above from @jonathan183 is also interesting as I am quite prone to letting myself get dehydrated.
 
I would never ever ever low carb again my experience was bad enough that it scared the life out of me.
My ketones have been fine with fasting and I will always keep an eye on them still. I eat my breakfast in the morning and have a big dinner at around 2:00pm then I fast, I feel better for it, so far so good
 
Dudette1 said:
I would never ever ever low carb again my experience was bad enough that it scared the life out of me.
My ketones have been fine with fasting and I will always keep an eye on them still. I eat my breakfast in the morning and have a big dinner at around 2:00pm then I fast, I feel better for it, so far so good
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Like so many on this site have reported, our ability to tolerate carbs regardless of diabetes type, is so variable and probably some genetic factors. I don't have a sweet tooth, but would love to more frequently indulge in artisan bread and various potato dishes - sadly not realistic as I spike very high with even small portions of these and my insulin ratios to control suggest significant temporary insulin resistance. Perhaps a giveaway was that 30 years prior to diagnosis I could only lose weight on the classic Atkins diet. Low fat, low calorie had no effect. Do what works for you!

Edit - I typically eat 1-2 times a day and with 16 hour fasting window - keeps my weight stable, but not losing.
 
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It’s a weird not so wonderful thing having diabetes, definitely agree with that. Everyone should do what’s best for them and enjoy what you can.
 
beerandbackpack said:
You should let your doctor know so that he adjusts insulin if needed. My MIL fasted for 12 h a few days in a row and ended up with severe sight issues.
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Most T1s adjust their own doses on a daily basis.
If your insulin doses are correct, the basal should keep you steady in the absence of food, and you add bolus insulin depending on what you eat (and some other factors).

If fasting for 12 hours (many people do this every day between dinner and breakfast, although many others like a midnight snack) caused your MIL serious problems, I guess her basal dose wasn't tailored to her needs.
What caused the sight issues? Did she go high or low, and how did this affect her sight in only a couple of days?
Is your MIL a T1 on the usual basal/bolus regime, or was she perhaps using a mixed insulin? Fasting on mixed insulin is close to impossible.
 
Antje77 said:
Most T1s adjust their own doses on a daily basis.
If your insulin doses are correct, the basal should keep you steady in the absence of food, and you add bolus insulin depending on what you eat (and some other factors).

If fasting for 12 hours (many people do this every day between dinner and breakfast, although many others like a midnight snack) caused your MIL serious problems, I guess her basal dose wasn't tailored to her needs.
What caused the sight issues? Did she go high or low, and how did this affect her sight in only a couple of days?
Is your MIL a T1 on the usual basal/bolus regime, or was she perhaps using a mixed insulin? Fasting on mixed insulin is close to impossible.
Click to expand...

Hi Antje77! She fasts between dinner and breakfast as you mentioned, as most people do. But what I meant - and sorry if it wasn't clear - she also fasted the following day after having breakfast so from 08 am to 08 pm approximately. her doctor told her that fasting messes with her daily insulin doses and can be dangerous to her. Each person is different, but it might be worth it to check with the doctor first.
 
beerandbackpack said:
her doctor told her that fasting messes with her daily insulin doses and can be dangerous to her.
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The doctor is correct if she's on fixed doses of basal and bolus, or on a mixed insulin.

Most T1's test multiple times a day (and more often if they do something unusual, like fasting) or use a CGM, and they know how to use correction doses and how to calculate doses based on what they eat.
The currently standard basal and bolus approach, be it through pens or pump, is designed to be flexible.
 
SherwoodT1 said:
I'm incredibly new to this, and heed the advice of others who've lived with t1 diabetes more than what I'll say. But, I'd be conscious of checking ketones to begin with. As far as I know, you can encourage ketogenesis by fasting, increasing the risk of dka. It may be best to speak with your diabetes team about this they'll provide better, tailored advice to your situation.
Click to expand...
Its a valid concern but actuaully having nutritional level of ketones is desirable as they act as fuel . Insulin is still needed for a type 1 not making very much though because in addition to ketones the body will continue to make glucose via the liver.
As others have commented, I have done plenty of fasting accidentally or on purpose and as long as the background insulin is going in, the greater risk is of going low.
 
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