• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

pre/post meal readings and spikes

aqualung

Well-Known Member
Messages
695
Type of diabetes
Prediabetes
Treatment type
Diet only
Sorry I have yet another bg reading question.

Scenario 1: pre meal reading of 4.3 post meal reading of 6.5

scenario 2: pre meal reading of 5.5 post meal reading of 6.5

Should I be more concerned about scenario 1 as the spike is greater or should I just be looking at the post meal reading of 6.5 and not take in account the pre meal reading?

Does this make sense or am I complicating the issue and confusing myself?
 
Scenario 1 & 2 are both good readings. Remember the possibility of up to 20% tolerance too in results. I think it's good to ask questions and it's clear you are managing very good control so I would be happy with those readings and try not to become overly concerned with slight variations.
 
Scenario 1 & 2 are both good readings. Remember the possibility of up to 20% tolerance too in results. I think it's good to ask questions and it's clear you are managing very good control so I would be happy with those readings and try not to become overly concerned with slight variations.

thanks for your reply. For my question I didn't use very good numbers! What I meant is if scenario 1 has a low pre meal reading and post meal at say 6 and scenario 2 has a higher pre meal reading but post meal reading still at 6 which is better the one with the smaller difference between pre and post readings or is the final reading important ie a reading of 6 is good, 9 isn't regardless of the pre and post readings?
 
The lower the difference the better but just remember these meters are just a guide, they're not accurate. I always think a difference of about 2mmol between pre meal and post meal reading is acceptable. If the difference is 4 or 5, perhaps avoid that food or reduce the amount.
 
The lower the difference the better but just remember these meters are just a guide, they're not accurate. I always think a difference of about 2mmol between pre meal and post meal reading is acceptable. If the difference is 4 or 5, perhaps avoid that food or reduce the amount.

Just to add to the confusion I have a cough and cold so my bg seems to be all over the place.
 
also remember that your pancreas releases insulin in response to rising sugars so if you don't increase so much on meal 2 it doesn't mean it is any better or worse than meal 1 as long as you remain at reasonable targets (which you need to set for yourself).

Flame on - lol
 
I don't think the size of the spike matters so much as long as the top of the spike is within target.

However, and it is a big however, I have been forced into testing before and at 1 hour, 2 hours and often at 2.5 hours every time I test, which is a bind. This is because my peaks vary all the time between 1 hour and 2.5 hours. If my 2 hour reading is higher than 1 hour I have to keep going until it goes down. . I can't trust my 2 hour reading to be my peak. I am probably going overboard with this, but I am pedantic!
 
I see the exact same @Bluetit1802 but I can now guess from the composition of my meals whether it is going to be a 1 or 2 hour peak or 3 on one occasion. The more fat laden the longer it is
 
my fasting bg was 5.7 this morning. I had an omelette and a mug of tea for breakfast. At 2 hours my bg was 6.1. Normally I would only have tested at 2 hours but I decided to test again at 2 1/2 hours - it was 6.6. At 3 hours it was down to 5.7.

I normally test at 2 hours but should I be testing at 2 1/2 hours as it looks as if that was when I peaked today? Maybe my bg levels weren't quite as good as thought they were as I was testing too soon:(

Also, do antibiotics affect bg levels?
 
If you are testing a new meal as opposed to testing general trends, I have come to the conclusion it is necessary to test at 1hour and 2 hours, then if it hasn't gone down at 2 hours, test again every half an hour until it does. Otherwise you don't know what the peak is. As I said, some of my peaks are at 1 hour, some at 2 hours, and some at 2.5 hours. As Andrew said, the more fat the longer it takes to peak.
 
If you are testing a new meal as opposed to testing general trends, I have come to the conclusion it is necessary to test at 1hour and 2 hours, then if it hasn't gone down at 2 hours, test again every half an hour until it does. Otherwise you don't know what the peak is. As I said, some of my peaks are at 1 hour, some at 2 hours, and some at 2.5 hours. As Andrew said, the more fat the longer it takes to peak.

thanks! I need to revise my testing! I thought my levels were OK now I am not so sure:( I am now even more confused!
 
should I be testing at 2 hours and seeing what the difference is between pre and post meal levels or should I continue every half hour until I see that the level is going down?
 
should I be testing at 2 hours and seeing what the difference is between pre and post meal levels or should I continue every half hour until I see that the level is going down?
Yes test pre and at 2 hours. If it is high at 2 hours test at 2.5.

Personally, I also test after exercise. So lets say I eat at 1200 and at 1230 I go for a walk for 45 mins I will test at 1315 and then at 2 hours. I will also have the same meal several times to see a patter for that food both with exercise and without. So I know that I can handle a slice of sponge cake with royal icing but I will do a 20 minute walk at about 40 mins after if I want to keep the spike to below 7 (higher and faster carbs than I am used to). Generally, I like to exercise to flatten my blood profile whenever I can and it doesn't take much.

I don't know if that will help or will confuse you more
 
If you want to know the peak it is best to test at 1 hour and 2 hours, and then if it hasn't gone down at 2 hours, test again at 2.5 hours. Hopefully it will have gone down by then. If not, test again at 3 hours. I don't think the difference between pre-meal and post-meal matters a great deal, just the peak. Of course, the higher you are pre-meal, the higher the peak will be. Does this make sense?
 
my pre lunch level was 4.8. After 2 hours it was 6.00. Previously I was stopping at 2 hours but of course it could still be going up - this is the bit that I hadn't fully understood. So I will test again at 2 1/2 hours

I thought today as I was walking the dog that I have my 2nd Hba1c test next week which means I have been low carbing and testing for 6 months and I still don't know what I am doing:( my mood did not match the nice sunny day we have had today
 
my pre lunch level was 4.8. After 2 hours it was 6.00. Previously I was stopping at 2 hours but of course it could still be going up - this is the bit that I hadn't fully understood. So I will test again at 2 1/2 hours

I thought today as I was walking the dog that I have my 2nd Hba1c test next week which means I have been low carbing and testing for 6 months and I still don't know what I am doing:( my mood did not match the nice sunny day we have had today

yay tested at 2 1/2 hours and it was 5.6 so going down.
 
my pre lunch level was 4.8. After 2 hours it was 6.00. Previously I was stopping at 2 hours but of course it could still be going up - this is the bit that I hadn't fully understood. So I will test again at 2 1/2 hours

Your reading of 6.0 could have been going down as well as up! Several of my peaks have been at 1 hour
 
I have now been testing at 1 hour and then half hourly intervals until my bg level goes down. I now realise that only testing at 2 hours misses out information and made me think my peaks were not as high as they actually were. My pre lunch level was 5.3, after 1 hour it was 6.3 and at 1 1/2 hours it was 5.7. At 2 hours it will probably be lower (I am not going to test as it has gone down and whilst I know it is important I also have to make my strips last as long as possible) and if I had only tested at 2 hours I would have missed the peak and assumed that the food made my bg rise less than I thought.
 
Back
Top