Help me understand rises in BS after eating

NewbieHelp said:

Hi All
As mentioned in another thread, I’ve probably become a little too obsessed about testing my BS. To try to understand and stop myself stressing can any answer these question simple terms please….

Does everyone’s BS spike after eating carbs or is it just us diabetics?

I should be testing just before eating a meal, and 2 hours after to ensure BS hasn’t risen by more than 2 at the two hour mark?

Is it normal to have an increase of more than 2 within the 2 hours but then drop back down within to within my normal levels at the 2 hour mark?

As I’m now walking longer and more strenuously, and getting fitter. I’ve noticed my BS is rising after exercise…. I know I need to avoid spikes but I still want to walk … are ‘exercise spikes’ better than ‘food spikes’ …. Or is there anything I can do to avoid/reduce them?

On the food spikes … I’ve been testing sometimes at the hour mark after eating and noticed some quite high numbers …. But these have dropped by the two hour mark after…. Are spikes at the hour mark normal or should I be avoiding these foods … ? Some of these spikes would be after eating foods that I would have never thought were and issue as I would be ok at 2 hours. I would not notice these spikes if I only test 2 hours after eating….

I’m also noticing some days I could eat the same foods …. Sometimes I would see a larger increase in levels at 2 hours than on other days… would this be normal?

Thanks again and sorry for all the questions…

Click to expand...

Hi

I'm going to post some links to research at the end, but this is a brief intro.... everyone's blood glucose will tend to rise if and when carbs are eaten. This is because carbs are converted/digested to glucose and pass into the blood stream. At the same time the body's insulin response is triggered, and that should have the effect of removing glucose from the blood and storing it - normally in the muscles or liver, or as bodyfat.

This is a dynamic process - both are happening at the same time. Glucose entering the system, and being taken out. You would expect to see peak blood glucose around 40 minutes after eating, but this will depend on you and how well your digestion works on carb, and how well your insulin system deals with glucose. My usual example is that a small latte will take me from around 5 to 9.5 in about half an hour (all from the milk lactose) and my system will have cleared it competely by about 1 hr 15.

Your testing regime is fine. Rises after carbs are absolutely normal and happen to everyone. I hate calling these normal rises "spikes" which makes them sound a bit dangerous and threatening. The two hour thing is where your levels should have fallen back to after your insulin response does its thing. If it doesn't fall back to close to where you started, that's a sign that the carb/glucose in what you ate overpowered you insulin response, and maybe you should think about not having that meal again or reducing its carb content.

In addition your liver will helpfully add glucose to your system whenever it thinks you need it. This is again perfectly normal and is often in response to adrenalin/cortisol (eg after stress or exercise). There is nothing you can do about that via food - it's really not linked to food at all, but your liver using stored energy.

Also - the fingerprick testing system can be inaccurate - around 15% error is acceptable. This means a true BG value of 6.0 might see returns of anything between 5.1 and 6.9 - testing is an indicator, not an absolute. Personally I would treat (eg) results of 5.3 and 5.7 as being essentially the same, but then I've been at this five years and am happy that I usually understand how my system responds to various things. It takes time to learn,and you'll get there.

Here's a couple of links to studies on normal BG reponses in non-diabetic people. You'll see they go up and down in response to food (carbs) - normal.

Forum issues won't let me post more than one link.....

NewbieHelp said:

Thanks for your responses….
So if I look at today’s figures

7.7 @ 5am when I woke up
No food consumed before my walk

10.2 directly after 6.25 km walk

Straight after walk I had strawberries and blackberries and 0 fat Greek yoghurts and a benecol …. Which normally would not increase my BS

30 mins after it had dropped to 8.6

And at 2 hour mark was down to 7.4

The fact it dropped down to 8.6 in 30 mins …. Is that good?

The fact it’s down to 7.4 at the 2 hour mark I assume it means this is ok?

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Here's a thing. Many people (not only diabetics) get a thing sometimes called dawn phenomenon. In general what happens is that livers set us up for the day by releasing glucose into the system. This often starts around 4am and from personal experience can go on for hours, into the afternoon, unless stopped.

It's possible that what you're seeing in the morning may be your liver's doing, particularly if you aren't eating anything. I've found that eating three almonds in enough to reassure my liver that I have food and that it can stop adding glucose. You might experiment with eating something small - nuts, hardboiled egg, that sort of thing, before your walk.

Your readings in high sevens to mid eights are much the same and could all be covered by general testing inaccuracy.

It's hard to be sure what's going on because there are a number of things that will affect your BG all going on at the same time. Eg - Dawn phenom; your exercise; the sugars in the fruit and the benecol will all potentially have some impact, and I wouldn't be confident about what exactly is going on.