• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

Very high sugar level after intermittent fasting

M

MikeSA

Member
Messages
14
Type of diabetes
Type 1
I have been doing a 24-hour intermittent fasting each day for the past week. However, although during the day at all times, my sugar levels are normal, two hours after I break my fast and at bedtime, the sugar level is astronomical - anything from 12mmol to 19mmol. But when I get up in the morning, the sugar level has normalized! It is usually under 6.5mmol.

I was diagnosed with Type 2 diabetes and, as Metformin did not work, I was put on Insulin. 16 units in the morning and 14 units before meals in the evening. When I am not fasting, my sugar level two hours after meals and at bedtime is usually under 10mmol and fasting level always normalizes when I get up (under 6.5 mmol) But why the astronomical jump in sugar levels when I resort to intermittent fasting when I check my sugar level two hours after a meal and at bedtime? I am not eating a lot of carbs when I break my fast, so what could possibly be the problem? Has someone an explanation?
 
Hi, so did they misdiagnose your type 2? Your sugars are high but not astronomical at 12-19, 24 hour fasting? So are you eating at different times each day or do you mean you are doing something like 16:8 in a 24 hour period? Do you use a freestyle libre or similar? what Is a typical break fast meal? Sorry for all the questions.

Ultimately, if fasting is not working, don’t fast. Lowering carbs is far more important in my opinion, I am a fan of intermittent fasting though.
 
Hi Fenn : Thanks for your prompt response. When I am on the 24-hour intermittent fast, I have no breakfast or lunch and only break my fast at dinner each day. Throughout the day, I do not eat anything but occasionally only drink a glass of water during the fast When I am not fasting, I get by with just a simple breakfast with just coffee and peanut butter with a bit of honey on toast. I do not have a Freestyle Libre meter. However, I have several meters but the one I am currently using is a Vivacheck meter and it appears to be accurate.

When I am on intermittent fasting, I do not inject with insulin in the mornings as I fear going into hypo during the day. I only inject with insulin before breaking my fast at dinner (usually around 6PM)

Do please let me know if you need any further information. Thanks
 
Mike are you type 1 or type 2? Were you initially misdiagnosed or is it a case your type 2 was severe enough they wanted you on insulin? Being on insulin does not change your type, just your treatment. Are you on fixed doses or basal/bolus? And which ones? All those things might effect the answers you get and I at least am a bit confused.
 
Could it be because you have suspended your morning (basal?) insulin and what you inject at dinner isn’t sufficient?
Could your ratios be different after a fast than when on a “normal” day?

NB I’m not an insulin user myself and am basing these guesses on my readings and insulin users posts over the years.
 
MikeSA said:
I was put on Insulin. 16 units in the morning and 14 units before meals in the evening.
Click to expand...
Is this a basal insulin or a mixed insulin?
Most T1's are on two different insulins, a basal (long acting) for background and a bolus (short acting) for food and corrections.
Such a basal bolus regime allows for irregular eating like intermittent fasting.
A set dose of a mixed insulin does not go together with intermittent fasting for a T1.
 
Thanks for all the responses. I am on Actraphene HM (ge). When I was first diagnosed over six years ago, I was prescribed Metformin but shortly afterwards, as Metformin apparently was not effective, insulin was prescribed. Initially, I had to inject 8 units in the mornings and 6 units in the evenings However, over the years, the dosage was gradually increase and currently I am on 16 units in the morning and 14 in the evenings.

When I am not on intermittent fasting, glucose levels at any time are somewhat plausible but, only when I am on intermittent fasting, the levels are rather high two hours after breaking my fast and at bedtime. I even tried increasing the evening insulin dosage by two to four units but then, at around 3 AM, I tend to experience a hypo and then have to have a snack to address the hypo.

When I am on intermittent fasting, if I do inject in the morning although not having any breakfast, it always results in a hypo a few hours later. I therefor do not inject when I am on intermittent fasting.

Further views and comments would be appreciated.
 
In my opinion it would be almost impossible for you to get this right on your current insulin, I would 100% speak to your doctor about changing your insulin to fast/slow insulins, you should find it way easier to directly affect food highs without the long term lows. I am currently intermittent fasting 18:6 and eating a keto diet, this has drastically reduced my insulin use, I would find it very difficult if I ate like this some days but not others, the only thing making the change in regime manageable is the weeks of practice it takes me to adjust to avoid the highs and lows. I’m sure if you explain your issues with your doctor they would understand, they usually respond well to people that try, as you clearly are. Best of luck.
 
You say you break your fast with something like peanut butter, toast and honey? All of these are carb heavy and this might be the reason that your number is ‘astronomical‘ to use your phrase. You’d be much better breaking your fast with a cheese omelette or bacon and eggs, something along those lines I would have thought.
 
No, No only when I am not on intermittent fasting that I have coffee and peanut butter on toast with a bit of honey for breakfast. When I am on intermittent fasting, I break my fast after a 24-hour period at dinner and I have a proper meal but try to omit carbs. I cannot understand why then two hours after dinner and at bedtime sugar levels are rather high but, when I get up in the morning, the sugar level has somewhat normalized! Perhaps the insulin I am taking is not acting fast enough.
 
The amount of insulin you take will be dependant on the food you eat and drink at time of breaking your fast which im assuming you already know. Interesting your not eating a lot of carbs which is also good. You say they normalise over night which is a great sign so id look to take insulin earlier before eating or could be insulin resistance which is a bit a rabbit hole topic in itself. multiple experimenting prob needed to correct that spike.
 
MikeSA is on a mixed insulin so it's impossible to adjust insulin depending on food and impossible to give corrections.
 
Antje77 said:
MikeSA is on a mixed insulin so it's impossible to adjust insulin depending on food and impossible to give corrections.
Click to expand...
Sorry. I didnt realise such an insulin even existed. Shows how out of touch i am with diabetes. Type 1 for 42 years but never been involved in any diabetes community.

Doing a lot of research myself for what you could call a mid life crisis !

Came across this forum so joined few hours ago for my own education. What has astounded me is how diabetes is so prevelant now. When diagnosed me and family didnt know a single person diagnosed with diabetes within primary, high school, friends or family (very large family scattered around the world).

I hope op finds a solution
 
If you are actually T2, then you may have Insulin resistance so that your mealtime post partum results remain high because the insulin is not so effective as it should be. i am not an insulin user, but this might be a possibility. The 2 part regime suggested by Antje and others would probably give you flexibility.
 
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn More.…