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When does testing after a meal become before?

N

NineToTheSky_

Member
Messages
11
Type of diabetes
Type 2
I'm never sure when taking my blood glucose readings becomes before a meal rather than after. For example, if I have my lunch at 1.00pm and my supper at 7.30pm, at what point should I record it it as after lunch or before supper?
 
I normally test just before eating then at one hour after and then again at two hours after eating counting from first bite of meal. I do this for each meal.
 
The idea is to test immediately before a meal, then again at set times after your first bite. 2 hours after is the normal time, but you can also test at 1 hour or 3 hours, The 2 hour mark is the only one we have NHS guidance target for.

It is the rise from before to 2 hours after first bite that is important.
 
As others have said .. best to test just before eating and 2 hours after .. its the rise in numbers that you need to see..
 
NineToTheSky_ said:
I'm never sure when taking my blood glucose readings becomes before a meal rather than after. For example, if I have my lunch at 1.00pm and my supper at 7.30pm, at what point should I record it it as after lunch or before supper?
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If you're testing how your lunch affects your blood sugar, test at 1pm just before you start lunch, then test again at 3pm (ie two hours after first bite of lunch).

You're testing for a purpose so the timing of the tests reflects that.
 
Not everyone agrees with timing from first bite. Some, like me, think it is logical to time from last bite. Unless you are having a very long meal it probably doesn't make much difference, just be consistent.
 
Mr_Pot said:
Not everyone agrees with timing from first bite. Some, like me, think it is logical to time from last bite. Unless you are having a very long meal it probably doesn't make much difference, just be consistent.
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It's not a case of agreeing. The 'first bite' is the recognised way of postprandial testing.

People are free to test whenever they choose, of course, but a postprandial test starts from first bite due to the metabolic processes triggered.
 
Just be consistent - it is an experiment to find out what your body can deal with, the type of food and the amounts. If you use the readings to determine what you can and can't eat to stop the rise in BG going over 2 whole numbers between before and two hours after, that is a good start - once you sort out the meals you can eat then you don't really need to keep on testing for them - unless you think there might be some difference in how you are coping.
Over time you should be able to see the way you should eat in a series of low BG levels.
The more you stick to a low carb way of eating the less strain on your metabolism and the more normal it will, hopefully, become.
 
NineToTheSky_ said:
I'm never sure when taking my blood glucose readings becomes before a meal rather than after. For example, if I have my lunch at 1.00pm and my supper at 7.30pm, at what point should I record it it as after lunch or before supper?
Click to expand...
For me, around two hours after unless I'm 'spiking' (getting high readings). I test before a meal, have a dose of insulin and wait around 15-20 minutes.
 
Mr_Pot said:
Recognised by whom?
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The medical/science professions :)

When you read about postprandial testing, the times given eg Two Hour PP test, etc are timed from 'first bite'. This is because the first bite starts off a chain of metabolic events, one of which involves insulin. The target postprandial blood sugar levels given on this site and elsewhere are timed from first bite.
 
We will have to agree to differ. I can't see how my stomach can tell from my first bite of a starter what I am going to have for dessert 30 mins later. I think the first bite idea comes from the GTT where where the whole "meal" only takes about 30 seconds.
 
If the test is 2 hours from first bite and this is what medical science recommends then why do doctors and nurses say T2's do not need to test at all which is what most are told
 
I also wonder about testing after first bite ,ok if you are just eating a quick lunch but what if you are eating with friends and you have a starter then a main and a sweet or cheese in my case and maybe a couple of glasses of wine with the meal you may be eating for 1 and a half hours or so .If you test half an hour later surely that can't give an accurate reading ?
CAROL
 
Pinkorchid said:
why do doctors and nurses say T2's do not need to test at all
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Mainly because they are often part of the problem, rather than part of the solution.

Everyone is different, and has different ways of eating

The advice to test at intervals after bite #1 is generic, and of course may not suit everyone.

As in all things, listen to the advice and then make your own mind up.
 
Mr_Pot said:
We will have to agree to differ. I can't see how my stomach can tell from my first bite of a starter what I am going to have for dessert 30 mins later. I think the first bite idea comes from the GTT where where the whole "meal" only takes about 30 seconds.
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I'm simply telling you the facts. You're free to test when you want :) The 'start time' isn't a matter of opinion. There's an actual answer to that. If people want to disregard that and set up their own testing schedules they can, but a PP test starts at the first bite.

The PP test is to see if blood sugar returns to normal after two hours. The metabolic signal starts at the first bite and triggers a cascade of metabolic events. In people without diabetes, those events ensure the blood sugar has returned to normal within two hours. That's what the test is. So we can compare our response and our control with that to see how we do. The targets given for the after meal tests are from first bite. So if you choose to test differently, you'll need to consider if those targets need adjusting to take that into account.

Obviously something like a buffet that took place over an extended length of time isn't going to fit in to the PP testing schedule, but those are special circumstances.

@carty For meals out such as you described, I tend to test regularly anyway as we have to guess carbs. I'd treat an extended meal like that in the same way I treat a buffet.
 
Pinkorchid said:
If the test is 2 hours from first bite and this is what medical science recommends then why do doctors and nurses say T2's do not need to test at all which is what most are told
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Unfortunately the answer is NHS budget restrictions

There has to be a standard for scientists measuring the effectiveness of medication/diets which is completely different from Doctors prescribing test strips for patients not at risk of hypo's. I am sure you already know this @Pinkorchid.
 
I was told by my doctor when I was first diagnosed to test first thing in the morning, 2 hours after lunch and before I went to bed. I tested more often to get a better idea of what was going on. I tested before lunch and then 2 or 3 hours after and then the same for dinner.

it really help me understand what and how much and what I could eat. I was able to get a handle on it fast and now I was told I only needed to test myself first thing in the morning since I have it under control.
 
I (usually) test immediately before I start to eat to give me a base figure for any resulting rises due to a particular food or meal - the size of any rise is just as important to me as the post meal figure.

If I eat something more carby than normal I may also test an hour after starting to eat as this is often when any real spikes can occur.

I still test even though I generally know what's going on food wise, but I find that things other than my diet can also affect my glucose levels, and so my overall control...

carty said:
I also wonder about testing after first bite ,ok if you are just eating a quick lunch but what if you are eating with friends and you have a starter then a main and a sweet or cheese in my case and maybe a couple of glasses of wine with the meal you may be eating for 1 and a half hours or so .If you test half an hour later surely that can't give an accurate reading ?
CAROL
Click to expand...

The "rules" can also be used as a basic guide, so you can use common sense and your reasoning for any particular test to adjust timings if needs be - just consider what you're hoping to discover and test accordingly, bearing in mind the standard recommendations. Or if you really want to see what goes on, try wearing Freestyle Libre sensors for a while.

Robbity
 
Saliva contains enzymes that start to break down your food in your mouth this triggers the the rest of the digestive system.

That is why from first bite except to a large degree for me as I no longer have most of my saliva glands so do not produce saliva much.
 
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