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How quickly are sugars/carbs processed?

J

JSBr

Member
Messages
11
Type of diabetes
Other
Treatment type
Other
How quickly after eating something would you expect to see an effect on a finger prick test?
I’ve seen mentions of minutes on this forum.
Also why is it recommended that you test 2 hours after a meal? Is this because it would be expected that your body should have dealt with the consumed carbs etc. in that time, or is it because this should be the peak time for blood sugar effects?
 
Hi, 2 hours is usually the peak time that your blood glucose would be affected by any food that you've eaten Testing before gives you your base line and then testing 2 hours after will tell you if you have had a reaction, more than a 2 mmol/l rise is classed as a spike.
 
How fast depends on a bunch of factors. Liquid carbs hit the system in minutes. Carbs paired with fats or in a lesser degree, fibers, don't get processed until an hour or so has gone by. Fast carbs like straight sugar or honey get into the blood stream faster than from say, wholemeal bread. That's why say, orange juice is a faster and more effective hypo treatment than french fries. They could have the same carb load, but get into your system at a different rate. So it's entirely dependent on your metabolism, combined with what the carbs enter your body as.

As for the two hours after, that's not the biggest spike... On average you spike -provided there is a spike, of course- about an hour in for a meal, it's at the two hour mark that you can more or less tell whether your body could cope what you put in there. So it is often by no means the actual spike moment. If you want to know what your highs are, you could make a curve... Test every 30 minutes or every hour, and make a graph from there. Costs you a lot of strips, though, but as an experiment, it could answer some of your questions.
 
Have you heard of a glucose tolerance test?

Tolerance to glucose, carbs, sugars, and even protein and fats (in very small amounts) as @JoKalsbeek has said will impact on your blood glucose levels. It all depends on how tolerant you are to them, will effect them!
We are all different!
Like me, I have a very weak first phase insulin response. That means I don't have enough insulin initially to stop my blood glucose levels going abnormally high after carbs, and of course how much carbs will skew it!
You may not have this, or you are insulin resistant, . It depends on the individual.
My spike after carbs is roughly 45 minutes, others will be around this or longer or shorter.

Only experience and experimenting with food will give you an idea which foods to either, stay away from, reduce portion size, or have and enjoy!

In the end, it's about preventing high spikes, that will improve your diabetic levels.
Two hours from first bite your pre meal reading gives you baselines to let you decide which foods you can tolerate. Over two mmols, and something in that meal is causing this reading. But if it is within, then it's good!

However, sorry, not trying to confuse, but a few, have found that their spikes can be longer than two hours. But only by testing can you find out!
 
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I tend to agree with Jo , and as I eat a low carb, ketogenic style diet, I expect to see some sort of a rise - but not necessarily a spike - around the middle of the 2 hour period, and for my levels to be coming or have come down at the 2 hour point. But it depends on what I've eaten and in what combinations, and in general carbs will be faster acting, more spikey than fats.

I found the most useful and informative way to discover how different foods could affect me was by wearing a Libre sensor. Doing this both confirmed what I'd already learned from my finger prick tets but additionally showed me in much greater detail what exactly was going on 24/7.
 
Thanks for that info.
 
Thanks. That’s a useful suggestion.
 
Thanks.
 
In my experience it depends on a number of things - the carb source, for example, or whether the food is hot or cold. A CGM will show you this very clearly. For me, I know hot milk (in a latte) will hit my bloodstream in about a minute and continue to climb for about 20 minutes. Generally back to normal in half an hour, so a fingerprick test probably wouldn't have caught it.

The other thing is that rise and fall in blood glucose levels is a normal thing and happens to non-diabetic people, in response to the same sorts of stimulus. It's just that by definition if you're not diabetic, your system handles the glucose much more quickly and efficiently.

The plus two hour test is to see how well your system dealt with the glucose produced from your food. It should be on the way down at that point. I don't think there's much point chasing the high point (although a CGM will show it) as it's high levels over time that's the issue, not a short-lived spike. I would be much happier with a rise to 11 and a drop to starting point within half an hour, than a rise to 8.5 that lasted six hours.
 
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