What is going on? Glucose rising with no food?

[Nexus6]

Possible prediabetes and I've been following all the amazing advice (very low to low carb, some intermittent fasting (thanks Dr. Fung) have lost about 25 pounds etc.)

Local pharmacy was recently doing an A1C clinic and I tested at a 5.1 (yeah!!) after a good month to 6 weeks of LC etc. - things seem to be working. Previous A1C tests from Dr. office was right at the borderline prediabetes level as was fasting glucose. Still have to go for a follow-up fasting test and GTT.

Anyways, I've been glucose testing at home like crazy, experimenting with foods etc to keep everything nice and steady and low and thought I had it mostly figured out, but then this happens...

Wake up this morning, shower etc, and take a reading....6.0. A little higher than normal...but I often see numbers in that area if I have a horrible/stressful sleep (which I did last night). It snowed a little last night, so before hopping in the car to work, I do a quick shovel (nothing too strenuous), drive to work, and just curious to see if it DROPPED, I take another reading and it's 7.7 ?!? What happened? I'll take another reading in a while...but I'm confused.

 

[Guzzler]

Bad night's sleep coupled with taking a shower before testing then some shovelling all mixed in with a liver dump. Try changing out some of those things and carry on testing.

 

[Deleted Account]

There are many things which affect BG including food, exercise, stress, illness, time of day, month, year, weather, drugs, ...

I suspect you are experiencing the Dawn Phenomenon - your liver dumping a load of glucose in your blood to help you start your day. There are a lot of threads about this for you to peruse.

 

[Nexus6]

Bad night's sleep coupled with taking a shower before testing then some shovelling all mixed in with a liver dump. Try changing out some of those things and carry on testing.

So you are saying I should be testing glucose AS SOON as I wake up? For example, it's very typical for me to "wake up" around 5:30am (have to use washroom), then back to bed until 7:00am (normal alarm time to go to work). Would the 7:00am time be the most appropriate time to test? 5:30? 7:00?

When I have to go for follow-up fasting tests, is it best to schedule as early as possible in the morning, or should I wait for later on the in the morning (I am perfectly OK with keeping my fast for any length of time). What is going to provide the most "true" or accurate numbers to the Dr. My glucose numbers usually drop as the morning goes on while fasting.

I suspect you are experiencing the Dawn Phenomenon - your liver dumping a load of glucose in your blood to help you start your day. There are a lot of threads about this for you to peruse.

So if Dawn Phenomenon happens often, do I WANT to get a fasting test WHILE this is happening? Or do I let the typical rush "pass" and then get the test? Sorry if I'm not explaining my confusion correctly...

For example...do I schedule the test when I know the levels will be higher from DP, and then explain to the Dr. "why" I think it was very high? Or, do I schedule the blood test for AFTER the effect of DP has dropped and get a lower glucose reading? What will the Dr. want to see?

Or should I work on eliminating DP? Is that possible? Still on weight loss pattern and have another 15 pounds to go to my goal...I'm 5'10" tall (have muscular/heavy build) - I want to get to 185 pounds. Currently down to 200. Started about 6 weeks ago at 225.

 

[Guzzler]

Yes, test your fbg on waking at seven but try to remember to wash your hands first.

Personall I would try to make an appt for blood draws earlier rather than later in the morning.

 

[Bluetit1802]

If you want a true fasting reading, you need to do it after you wake up and leave your bed to start the day. Any activity after that is likely to cause a rise as your liver will be dumping glucose in your bloodstream to help your energy requirements. This is natural and normal. When we go to the surgery for a fasting test, the results can be unreliable due to having plenty of activity beforehand, stress about the forthcoming test, rushing about, driving, whatever. However, that cannot be helped, and is why fasting plasma blood tests are no longer used for diagnosis.

 

[ziggy_w]

Hi @Nexus6,

The reason that your blood sugars rise when fasting might also relate to insulin. When we fast, our body does not require much insulin, so the pancreas makes very little. One of the functions of insulin includes stopping the liver from releasing glucose. So, not eating anything might cause your liver to release more glucose.

I have experienced that this tends to stop after you have been low-carbing for a while. For me, it took about half a year. (Maybe after the liver had lost most of its extra fat -- but I have really no way of knowing).

By GTT do you mean a glucose tolerance test? Does your GP that you are low carbing? Low carbing can affect the results becaause your pancreas is no longer used to making lots of insulin. It is generally recommended that you carb up before doing this. @Bluetit1802 can probably tell you a lot more about this because she has recently done one at home.

 

[Bluetit1802]

By GTT do you mean a glucose tolerance test? Does your GP that you are low carbing? Low carbing can affect the results becaause your pancreas is no longer used to making lots of insulin. It is generally recommended that you carb up before doing this. @Bluetit1802 can probably tell you a lot more about this because she has recently done one at home.

@ziggy_w is right. The guidance for an OGTT is to eat at least 150g of carbs daily for 3 days prior to the test. These are the instructions issued to GPs as recommended by the WHO.. However, as most people eat at least that amount as part of their normal diet, GP's tend not to tell you this - they aren't expecting you to be on a low carb diet. It is, of course, entirely up to you whether you follow this guidance or not. Personally, I fully intended to follow it but failed miserably as I couldn't bring myself to eat that many carbs, even for 3 days.

http://penlanhealthcare.com/uploads/Rapilose-OGTT-Instructions-For-Use.pdf

 

[LittleGreyCat]

There seem to be two different blood tests going on here; finger prick and at the Doctor's.

Which tests are you worried about? The finger prick seems to be a normal liver dump.

I would have thought that by now you were beyond a fasting blood glucose test and just on HbA1c. To be clear, HbA1c measures your long term blood glucose levels and so is not affected by what your levels are on the day. This test doesn't have to be fasting.

If you are going for an OGTT then that should be a fasting test (so nothing is competing with the glucose), and generally taken in the morning because most people fast overnight, but as far as I know your starting level isn't that significant. It is what your levels are after taking the glucose, how far they go up and how quickly they come down.

So, don't panic. Just do your normal stuff (apart from eating and drinking).
I suspect you are over thinking this a little.

 

[sally and james]

I never quite see the point of a first thing in the morning fasting test. This dawn phenomena thing is such an unreliable beast and, what are you going to do about the results anyway? My thoughts on a more useful, same time every day test is the one before your evening meal, often the lowest time of day in our experience. This is assuming that you haven't worked your way through a packet of biscuits during the afternoon!! It also doubles as your pre-meal test.
Sally

 

[Rustytypin]

Hi @Nexus6 , I have been Lo carbing for well over a year now, and I find my FBG is usually in the low sixes, unless I have had a heavy carb day (around 80gm), I have given up trying to lower it, it seems to be the way I am!
As regards exercise, light short periods seem up up my BG a bit, but 2 to three hours bike riding will put me into the 4s

 

[Nexus6]

There are many things which affect BG including food, exercise, stress, illness, time of day, month, year, weather, drugs, ...

I suspect you are experiencing the Dawn Phenomenon - your liver dumping a load of glucose in your blood to help you start your day. There are a lot of threads about this for you to peruse.

 

[Nexus6]

Thanks for all the advice and info everyone. I'll certainly do some more reading about Dawn Syndrome etc. For example, I'm now (still fasted state as I am doing an intermittent fasting day) at a 5.2. So I can see what the "fasted" glucose reading does not seem like a reliable way to test.