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What is considered normal fasting blood sugar?

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I've seen conflicting information about this. Some sources say it should be under 5.5 - according to other sources it should be under 6.0?
 
Hi Susan 369, welcome to the forum

For me, this isn't a simple answer as things other than food can affect your BG. That includes but is not limited to things like illness, stress, ambient temperature, exercise etc. I seem to recall reading a list of about 40 things that people had reported as affecting their BG level. In addition many people report "dawn phenomenon", where the liver helpfully dumps a load of glucose into the bloodstream to get you going in the morning, My morning (fasted) readings are still generally higher than everything else.

www.diabetes.co.uk

Normal and Diabetic Blood Sugar Level Ranges

Normal blood sugar ranges and blood sugar ranges for adults and children with type 1 diabetes, type 2 diabetes and blood sugar ranges to determine diabetes.
www.diabetes.co.uk www.diabetes.co.uk

If you look at this link (on the website this forum belongs to) you'll see a number of ranges - for non-diabetic folks, T2s etc. So you'll see a "normal for non-diabetics" and a "normal for T2 diabetics" range. That should tell you what you need to know.

My personal standards are to keep below 6.0 (fasted, before eating) and below 7.0 two hours after eating. After 3+ years on keto that is working.

Best of luck!
 
Thanks Kenny, that puts things into perspective! I can totally believe that factors other than food can affect BG. Sometimes I get hypo when I exercise and other times not, having eaten the exact same food at the exact same time doing the exact same things! It might also explain why my BG was significantly higher this morning (5.8) than the previous two days (4.9 and 5.1 respectively) - as I got up much earlier this morning. Interesting! Thanks for your reply!
 
Susan369 said:
Thanks Kenny, that puts things into perspective! I can totally believe that factors other than food can affect BG. Sometimes I get hypo when I exercise and other times not, having eaten the exact same food at the exact same time doing the exact same things! It might also explain why my BG was significantly higher this morning (5.8) than the previous two days (4.9 and 5.1 respectively) - as I got up much earlier this morning. Interesting! Thanks for your reply!
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No offense intended, but I personally would not call 5.8 compared to 4.9 or 5.1 "significantly" higher. Maybe if it was 20 I'd call it significantly higher, but the difference between 5.8 and 5.1 is probably just noise
 
plantae said:
No offense intended, but I personally would not call 5.8 compared to 4.9 or 5.1 "significantly" higher. Maybe if it was 20 I'd call it significantly higher, but the difference between 5.8 and 5.1 is probably just noise
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Well, there is certainly some permitted variance in meter readings, but it could equally be the other way round - lower readings are "really" 4.5, higher are 6.3. Who knows? There's simply no way of telling. Someone at the beginning of a blood glucose journey needs to be able to work out for themselves how their own bloods react.

My own readings have been and are fairly similar and after three years I'm pretty sure that does mean something. I wouldn't be so quick to dismiss early evidence as simply noise.
 
KennyA said:
Well, there is certainly some permitted variance in meter readings, but it could equally be the other way round - lower readings are "really" 4.5, higher are 6.3. Who knows? There's simply no way of telling. Someone at the beginning of a blood glucose journey needs to be able to work out for themselves how their own bloods react.

My own readings have been and are fairly similar and after three years I'm pretty sure that does mean something. I wouldn't be so quick to dismiss early evidence as simply noise.
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Ok, I'll not do that again
 
plantae said:
No offense intended, but I personally would not call 5.8 compared to 4.9 or 5.1 "significantly" higher. Maybe if it was 20 I'd call it significantly higher, but the difference between 5.8 and 5.1 is probably just noise
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Maybe I'm just over stressing it! I also have health anxiety, so I actually find your comment quite comforting! :) I haven't been diagnosed with diabetes, but I know something's up. I'm getting my levels checked at the surgery in a few weeks, but in the meantime I got myself a BG testing kit - it's just that fasting 5.8 would put me in the prediabetic range according to some sources. I just hope that's not the case. And I've been watching my carbs for a whole year now!
 
@Susan369, I use target ranges (based originally on the T2 ones on the link that @KennyA gave you) so instead of worrying over individual fasting figures which my liver generally dictates, I look at the time I'm within my target range. My meter can be set to do this and to monitor my results over various time periods. I get to see trends rather than individual, and often non food related, "wobbles" - which for me tend mainly be stress or pain/illness related.
 
I'm waiting for an ambulance right now because my BSLs are in the 1s. So my response might be confused. I really think that BSLs fluctuating between 5.1 and 5.8 is normal. They're not, in my opinion going to stay at a steady, say, 5.5; they'll go up and down a little bit and your meter will probably go up and down a little bit as well. But, yes, get medical advice. I don't think I'm assuming anything, but when fasting my BSLs go up and down and look like a sine curve... KennyA might be right though, I'm only new to this. I was mistaken to assume anything considering how new I am and he was right

Edit: Oh how I wish I was in the 5s right now :)
 
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plantae said:
I'm waiting for an ambulance right now because my BSLs are in the 1s. So my response might be confused. I really think that BSLs fluctuating between 5.1 and 5.8 is normal. They're not, in my opinion going to stay at a steady, say, 5.5; they'll go up and down a little bit and your meter will probably go up and down a little bit as well. But, yes, get medical advice. I don't think I'm assuming anything, but when fasting my BSLs go up and down and look like a sine curve... KennyA might be right though, I'm only new to this. I was mistaken to assume anything considering how new I am and he was right

Edit: Oh how I wish I was in the 5s right now :)
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I hope you're ok and it was just a false alarm? I did find with my meter (kinetik), if I didn't get enough blood, instead of showing an error, it comes back with a false low value!
 
I'm back down to 4.9 after some low carb snacking during the morning and a few cups of black tea with milk, so either the fasting 5.8 was a false reading or there could be other factors at play beyond my control . I can see how those CGM's can be helpful. I might invest in one for just two weeks to give me a better picture. I don't really enjoy pricking my fingers every five minutes :nailbiting: I'll wait for the results from the GP lab test first though. Even if I'm not diabetic, I will never go back to eating rubbish like I used to! I didn't realise just how much our eating habits can influence our health - now I'll just have to convince my husband to do the same! For me the wake-up call was high blood pressure - and I'm pretty sure the two are connected!
 
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Susan369 said:
I'm back down to 4.9 after some low carb snacking during the morning and a few cups of black tea with milk, so either the fasting 5.8 was a false reading or there could be other factors at play beyond my control . I can see how those CGM's can be helpful. I might invest in one for just two weeks to give me a better picture. I don't really enjoy pricking my fingers every five minutes :nailbiting: I'll wait for the results from the GP lab test first though. Even if I'm not diabetic, I will never go back to eating rubbish like I used to! I didn't realise just how much our eating habits can influence our health - now I'll just have to convince my husband to do the same! For me the wake-up call was high blood pressure - and I'm pretty sure the two are connected!
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A CGM will certainly show you things you can't find out from fingerpricks - what happens while you're asleep, for example. I'd never have discovered how quickly hot milk hits the bloodstream without it, because the hot milk spike for me is very high, very quick, but gone by the two hour mark. There have been one-off free trials from Abbott, who make the Libre. I used that a year or so back.
 
KennyA said:
A CGM will certainly show you things you can't find out from fingerpricks - what happens while you're asleep, for example. I'd never have discovered how quickly hot milk hits the bloodstream without it, because the hot milk spike for me is very high, very quick, but gone by the two hour mark. There have been one-off free trials from Abbott, who make the Libre. I used that a year or so back.
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Yes, I did read something about a free trial, but I think you have to be diagnosed with T2 to qualify. I'll look into it. At this point, I think I just want to try it out of curiosity. No way I would be able (or willing) to pay £100 on a monthly basis, but I can stretch to a one-off purchase to cover a two-week period if no trial is available. Interesting what you said about the hot milk!
 
Susan369 said:
Yes, I did read something about a free trial, but I think you have to be diagnosed with T2 to qualify. I'll look into it. At this point, I think I just want to try it out of curiosity. No way, I would be able (or willing) to pay £100 on a monthly basis, but I can stretch to a one-off purchase to cover a two-week period if no trial is available. Interesting what you said about the hot milk!
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Yes you do have to have a T2 diagnosis. Kind of essential info, sorry.
 
I've found a really good explanation as to why your fasting BG could be higher than your BG after low carb meals, which is what I was experiencing - and it's a good thing! You were right @KennyA - it is to do with the dawn phenomenon. Fascinating stuff - so much to learn!

 
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