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Intermittent fasting low blood sugar

Andy_Warlow

Well-Known Member
Messages
116
Type of diabetes
Type 2
Treatment type
Diet only
Dislikes
Cycling,
HI,

I had been Fasting for 20 hours and had a 4 hour eating window. For 4 days.

Anyway yesterday, was feeling sluggish and tired towards the end.

I checked my blood sugars and they where down at 4.

So I broke my fast on the 20 hours and then an hour after wards had a chocolate bar. As I think 4 is low.

Anyway went to bed and checked my blood only up to 6.5.

So is 4 too low a blood sugar?

So I have decided to have a re feed day. But nothing major just my usual low carb but have 3 meals today and then try the fasting again. Anyway advice?
 
Hi Andy, Is 4 too low is a difficult question. It is certainly low though!
I have never had a reading below 5 - even after a 3 day fast, but some (including @bulkbiker I think) have readings below 4 and feel fine.
The body needs to adapt to the BG range it is experiencing. Much lower or much higher and you are likely to feel unwell.

I don't think the chocolate was a good idea unless you are on Glic or Insulin and so at risk of a hypo.
 
Unless you are on blood sugar lowing medication like sulphonylureas or insulin, you should celebrate 4 mmol/l as a success.
 
o.k cheers, was just had a moment panic, that it was too low.

No meds at all, just diet and exercise.
 
As long as you are not on any sugar lowering Meds 4 is pretty fantastic reading. If you thought you needed to break your fast something a little more nutritious than chocolate like eggs or cheese would have been a better choice
 
My suggestion would be that one of the main benefits of intermittent fasting is to reduce glycogen stores in the liver, and by doing so, to ease into ketosis.
In which case, tanking up the glycogen stores with chocolate will undo a lot of the benefits of the IF.

although I TOTALLY get the desire to fuel up when bgs are lower than normal.

where do your bgs normally run at?
Your IF may have v successfully reduced some insulin resistance, effectively lowering your bg to ‘ideal/normal for you’.
My suggestion would be to replace the choc with something much lower carb, like nuts or cheese.
 

On day 3 of a fast I usually get my lowest numbers.. I think 3.4 mmol/l is the lowest I have ever captured.
The first time I went sub 4 it felt a bit odd (slightly light headed) but now I hardly notice at all (although for honesty I haven't done an extended fast for a while)
 
I have never fasted but frequently get readings in the 4’s without any ill effects. Recently I got my first sub 4, 3.9 at bedtime and felt fine in fact I just went to sleep as normal! I guess it’s just down to what levels your body is used to?
 
Hi all, cheers for the respones.

My usual blood is from 5-8 since I went low carb and exercised more.

Today my bg has been only up at 7.7 at highest.

5 when I woke this morning.

I had a normal low carb day of eating, no sugary sweets today.

So I am going to back on the 20 hour fasting again tomorrow.

I think I just panic, as I have seen a 4 before, thought it was too low.
 
Interesting..... I just had a mild hypo (3.7 according to my Libre)

I am neither low carbing nor IFing, but have stopped binge eating over the past few months. Although I suppose I have been IFing in a sense, because I don’t usually eat breakfast, so that means that most days I have a 6 hour eating window, increased to 9 hours if I get peckish in the evening. I would say my eating style now is carb aware, so probably lower carb than average and low sugar.

This morning I was hungry so I did have breakfast (porridge) and lunch was soup with a slice of granary bread, followed by an orange.

About 3.30pm I went for a walk, fairly brisk, out for just under 40 minutes. I do this daily. When I got back and sat down, I thought.... I feel a bit shaky.... a bit tired.... am I hypo? Yep - 3.7. Demanded food from surprised husband, 15 minutes and 12 mini breadsticks later - 4.9, feeling fine.

I’m on metformin and Trulicity, neither of which is supposed to cause hypos. I’m sure that, had I not eaten, my liver would have taken care of it anyway.

But, since I’m not low carbing or on insulin/sulfonylureas, how can it even happen?
 

Did you check on your glucose meter to? Sometimes on day 6 my libre gives me very inaccurate readings in the low 2's high 3's and my glucose meter is telling me im 9mmol/l so i always check on my meter now
 
Andy_Warlow said:
o.k cheers, was just had a moment panic, that it was too low.

No meds at all, just diet and exercise.
Click to expand...
4 is the floor for type 1s, it is the lower end of range. Chocolate is slow to treat levels though with the fat, so jelly baby, haribo etc will rise you up. Apple or something is a small carb slow release snack if needed when worried going too low.
Well done though on your success, sounds like you are doing so well with control. Not easy!
 
A Nurse told me that a person without diabetes would have a fasting reading of exactly 4.4. Don't know if that's true as there must be some variation in people but there you go.
 
A further reassurance that seeing a 4 is OK, from our main Diabetes.co.uk site:

For people with diabetes, blood sugar level targets are as follows:
  • Before meals : 4 to 7 mmol/L for people with type 1 or type 2 diabetes
Our body, if used to higher levels, can throw a wobbly (AKA false hypo) if it feels we've gone too low - I used to want to make a dash for a sugar source if this happened when I was first diagnosed, though I never went real hypo low.
 
KK123 said:
A Nurse told me that a person without diabetes would have a fasting reading of exactly 4.4. Don't know if that's true as there must be some variation in people but there you go.
Click to expand...

An endocrinologist I happen to know naturally runs his BG at around 3.5.
No, he is not diabetic (and he should know!).

So I think the nurse was less informed than they thought.
 
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