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2 hour after meal testing /Glycemic Load

rmz80

rmz80

Well-Known Member
Messages
332
Location
Leeds
Type of diabetes
Type 1
Treatment type
I do not have diabetes

One thing I’m not clear about is the idea of testing BG at 2 hours after a meal and whether it has any meaning. I can understand it being relevant if the meal carbs are in just the form of Glucose but meals tend to be a combination of fast carbs(sugars), slower carbs (starches) and fibre carbs .

Similarly; I am also doubtful about knowing the value of the Glycemic Load (GL) of a food as the look tables tend to list just one food rather than combinations.

As as example; If I have porridge (oats), milk and 2 spoonfuls of sugar. The sugar is a fast carb (and some of the milk). The oats will be a slow starchy carb with some very slow fibre carb content.

Thanks for any comments on GL and 2 hour testing
 
Interesting question posed by rmz80, which I'll try to answer to the best of my knowledge as I understand things.
Firstly taking a B/G reading before eating and then agan 2 hours lates (sometime it's also take at hourly intervals) will show just how well, or otherwise the individual is at coping with that particular combination of food/drink items in processing the resultant Glucose that when the the meal is broken down by the digestion process gives a rise in B/G levels.
We arn't all quite the same and some items might produce a greater rise in B/G levels (Spike) in one individual, more so than the same meal being consumed by another individual. This is why over time we each get to know what we can, and cannot eat.
The Glycaemic Index was first established by measuring the resultant B/G responce over a time period of a SINGLE type of food item and relates to consuming 100gms or 100ml of that item. This is purely a reference guide, as it's not really a practical proposition to eat 100gms of say 'Carrots' on the dinner plate at one sitting without experiencing some possible discomfort !!!!
For this reason real portions were then considered rather than 100g/100ml of the item, portions such as you would eat on a dinner plate, and still based on the Gi system the figures were ammended and become the Gl (Glycaemic Load) which is in reality a better indication of the effect of the food/drink item.
Combining a High Gl food item with a Low Gl food item on the same dinner plate will result in the (Average) value being around the mid position of the Gl initial values. The same can be said for multiple combinations of food/drink items which as you will probably agree would be impossible to accurately list due to all the countless combinations that this would create.
The simple answer is to eat according to your meter.
 
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@rmz80 The GL is just a guide to give you a rough idea. We're not machines so we can all react slightly differently. The best thing to do is to see what works for you. Eat the same meal and experiment with bolus timing and amounts. The GL just gives you a starting point.

The two hour test is because that's when your blood sugar should be back in range and that's what happens with people who don't have diabetes. It's also a commonly used measure eg somebody might be told to be under 8 at a two hour Postprandial test. It's a way to check your cntrol and your body's response to the meal. It doesnt mean you can't do additional,tests eg at one hour, three hours or whatever. Some people only test before their next meal, but that can miss some spikes.

These are all tools to help you get good control not infallible rules. The trick is to use what works for you as an individual so that you can keep in target as much as possible.
 
The reason i'm asking about the significance of a two hour test is that I can do without insulin for a meal (NovaRapid) by avoiding fast carbs (sugars) and waiting 4 hours not 2. I can get a BG of around 5.5 mmol at 4 hour. What significance would a spike at 2 hour mean?
 
rmz80 said:
Thanxs for this info I didn't know about this. I think i'll live with the spikes however as my HbA1c was only 31 mmol/mol last time.
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That is very low my last one was 30! But still swinging from spikes to lower levels causes the risk of long term health problems, you really should look at reducing the spikes x
 
rmz80 said:
Thanxs for this info I didn't know about this. I think i'll live with the spikes however as my HbA1c was only 31 mmol/mol last time.
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It's a balance early on after diagnosis. Perhaps that's something you could discuss with your doctor - what spike is acceptable. Personally, I pay more attention to my daily BS results in a situation like this because I don't like spikes.

It is, of course, ultimately your decision :)
 
azure said:
It's a balance early on after diagnosis. Perhaps that's something you could discuss with your doctor - what spike is acceptable. Personally, I pay more attention to my daily BS results in a situation like this because I don't like spikes.

It is, of course, ultimately your decision :)
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Changing the subject slightly how many blood checks a day would you do on a typical day?
 
rmz80 said:
Changing the subject slightly how many blood checks a day would you do on a typical day?
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It depends on what I'm doing, but as a rough ides I test between 7-14 times a day. Probably the average amount is 8-10 times a day.
 
azure said:
It depends on what I'm doing, but as a rough ides I test between 7-14 times a day. Probably the average amount is 8-10 times a day.
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I am just trying to form some sort of rule to what’s has been said to date. 8-10 tests a day=tight BG control particularly useful at controlling HbA1c. 4 tests a day=(in my case) looser control when HbA1c not particularly high. Would you agree?
 
rmz80 said:
I am just trying to form some sort of rule to what’s has been said to date. 8-10 tests a day=tight BG control particularly useful at controlling HbA1c. 4 tests a day=(in my case) looser control when HbA1c not particularly high. Would you agree?
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I'd never tell anyone how often to test, but I personally prefer to test more than 4 times a day to keep tight control.

You need to find what works for you and your lifestyle :)
 
azure said:
I'd never tell anyone how often to test, but I personally prefer to test more than 4 times a day to keep tight control.

You need to find what works for you and your lifestyle :)
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Reading the article; one of the key points (for me) is I split a lunch meal into 2, one at 11am the next at 2pm. I still eat the same amount though.
 
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