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+2mmol guideline.

Fleegle

Well-Known Member
Messages
775
Location
Denmead
Type of diabetes
Type 2
Treatment type
Diet only
I just want to understand something so any help or advice really gratefully appreciated.

I have been changing my eating patterns, got my BG down to a fasting to a reasonable level and trying to reduce calories for lunch.
This results in long periods of BG between 3.5 and 4.5.

Today when I had my evening meal - probably 12g carbs and the bulk of my day's calories my BG was at 4 before I started and I was starving. Within about 40mins my BG was 6.2. Now by time the first hour was up it was down to 5.7 and then climbing down well in the second hour.

Is the 2.2mmol rise in the first hour anything for me to be concerned about. I know that if I eat more regularly and do not fast my BG hovers around 5mmol and the same meal will raise my BG to about the same 6.2/6.4 - it is a regular recipe although the decline is much slower when starting from 5mmol.

I have read that your BG may rise quickly to 7.8 before declining and I get nowhere near that at all.
 
For me its a question of where the rise takes me, rather than how many mmol it is.
2.2 mmol rise from a 4 would be fine, from a 7 it wouldnt be - Ive always used the results ive got from testing how much a food raises BS together with my pre meal BS, to help guide food choices
 
I just want to understand something so any help or advice really gratefully appreciated.

I have been changing my eating patterns, got my BG down to a fasting to a reasonable level and trying to reduce calories for lunch.
This results in long periods of BG between 3.5 and 4.5.

Today when I had my evening meal - probably 12g carbs and the bulk of my day's calories my BG was at 4 before I started and I was starving. Within about 40mins my BG was 6.2. Now by time the first hour was up it was down to 5.7 and then climbing down well in the second hour.

Is the 2.2mmol rise in the first hour anything for me to be concerned about. I know that if I eat more regularly and do not fast my BG hovers around 5mmol and the same meal will raise my BG to about the same 6.2/6.4 - it is a regular recipe although the decline is much slower when starting from 5mmol.

I have read that your BG may rise quickly to 7.8 before declining and I get nowhere near that at all.

Hi @Fleegle,

As I see it, the 2.2 mmol rise at 40 minutes is absolutely fine. If I am not mistaken, the +2 mmol guideline says that your blood glucose levels should not have risen more than 2 mmol two hours after eating.

Congratulations by the way -- those blood sugar levels are fabulous.
 
I agree with @ziggy_w

A rise at 40 minutes is normal (irrespective of where you start). It is also normal to be well on your way back down, and hopefully all the way back down, at 2 hours. (as you almost were). The 2 hour level depends on how much fat there was in the meal, as a lot of fat will keep the rise lower but will prolong it, as might any low GI carbs.

You also need to take account of the fact your body is not used to seeing 4s and you have been fasting, and were starving hungry. Your liver may well have given you an unwelcome lift back up to where it wants you to be at some point in the process, meaning you would be unlikely to see that 4 any time after eating without a further period of fasting.

I would be delighted with those readings. Well done.
 
Take your "base line" BG level, then work out the "area under the graph" that is above that level, this tells you how "harmful" a meal was. So a spike of +4 for 1hr is about as bad as a spike of +2 for 2hrs. The increase in BG levels you are getting is not an issue.

Once we have emptied our liver of stored BG, we can eat too many carbs and yet not get a big increase in BG level, unless we repeat the "too many carbs" a few times. Hence checking BG after meals become less useful for anyone with a good level of control. (However, a blood keto meter may show if a single meal has too many carbs.)

There is nothing magic about +2 at 2hr apart from most people with Type2 can easily get a meal down to a level of carbs (and limited protein) that keeps them below it. Hence it is a good training tool to help people find the meals with too many carbs in them while they are starting to reduce their BG. It is also a great motivator as it shows us we have just had a "good meal", there is nothing better than a quick feedback cycle to drive process improvement.
 
Take your "base line" BG level, then work out the "area under the graph" that is above that level, this tells you how "harmful" a meal was. So a spike of +4 for 1hr is about as bad as a spike of +2 for 2hrs. The increase in BG levels you are getting is not an issue.

I agree it is the area under the curve that matters, but this can only be calculated with either a CGM or testing every 15 minutes to see when that curve finishes, and if there are any further bumps after the initial peak (which does happen depending on the contents of the meal) What it all boils down to, over a period of time, is the standard variance - some CGMs work this out. Sadly, the Libre doesn't. Or if it does I have never found out where. The length of time is important.
 
I just don't think post meal BG is a good indicator unless it clearly goes up a lot for a few hours, and it will not do for any of us that have already build the basic "low carb" into our life styles.
 
Where does a 2mmol guideline come from? ( what body?)

Good point, I put the word guideline because it is quite common to say "...if you get a 2mmol rise in...".
Guideline might be to strong a word - perhaps common parlance would be better.
 
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