Thanks you I’ll look into it. This is what’s confusing me a couple of years ago I went to the drs as I’d tested my sugar level (parents are type 2 so was comparing with them) and it was 11 after an hour and some exercise it went down to 4 and my dr said that was fine it was what it was meant to do. Now people are saying that’s not right it shouldn’t spike that high makes me think maybe this has been going on longer than my dr thinks though she did test me 18 months ago and 42 was the magic number
No surprise, but it depends on what you eat and who you are.
This is one of my favourite charts, from an excellent recent study part of which involved seeing what happened to the BG of several hundred non-diabetics after eating a standard bagel+cream cheese meal on two different days. The chart shows just six of the participants, represented by different colours, and what happened to them on the two different days. The glucose numbers are in American mg/dl so divide by 18 to get mmol/L.
Each person's profile didn't change very much between the two days, but there were huge differences between the ways people reacted.
Some people could go as high as ~11 after eating; a bunch of them could go well over 8. Some people peaked at < 60 min, others at 90+ min. Some were still not back to their starting levels after 2.5 hours.
There's a range of recent CGM studies showing similar pictures for non-diabetics. Setting single-number targets which are roughly where an "average" non-diabetic might be after 2 hours after an "average" meal is really not very useful but is basically where the targets you see mentioned come from.
If you're "naturally" the kind of person who went 10+ after eating a bagel before a diabetes DX, then it's not going to be very fruitful stressing about it after the DX. Non-diabetics can routinely go higher than 10, depending on who they are and what they eat.
This kind of study also undermines the usefulness of the GI/GL stuff
@Northerner mentions. The point is that there is no "absolute" GI/GL measure for a food. The ones you see quoted are average values typically from very small studies. But people's individuals reactions might have very little in common with these averages.
This chart is from another study, looking at hwo non-diabetics respond to different types of bread. Apologies for it being hard to read - like that in the original paper.
Anyway, the chart on the left shows *average* BG after eating various kinds of bread. As expected, the *average* peak is highest with high-GI white bread, and lowest with lower-GI oat bread.
But those averages conceal a huge range of individual responses, as shown in the second chart. The boxes represent the levels seen by 25% - 75% of participants; the line in the box the average; and the end points the highest and lowest levels seen.
You can see that plenty of people went higher with oat bread than they did with white, and so on. The range for spelt bread is remarkable!
Takeaway: GI/GL is a nice idea but individual variability is so great that having a single number for each type of food isn't very meaningful.
