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Blood Sugar Tests

Hi everyone!

OK, I was a little worried because I’ve had 3 fasting blood sugars taken by the doctor in the last 3 years which were all a little high for fasting. Scores of 101, 99 and 102 each one year apart. Now after the second one, they did a long term blood cell test that showed my blood sugar had been normal over the last several months.

But I decided to get a blood sugar tester. My grandpa developed diabetes and my father had fasting blood sugars like mine, but died from an infection that was in part due to poor circulation, so there was suspicion that he had blood sugar issues that weren’t getting detected.

I know that typically its carbs to spike blood sugar but I basically went to McDonald’s and got two McGriddle breakfast burritos. I could only finish one and a half. And I had coffee and about 16 ounces of milk. I know that its actually pretty isocaloric, but I never eat pure carbs anyway.

So I tested at 2, 3, 4 and 5 hours after the meal and also worked out and got the following:

2 hours: 87
Workout for 30 minutes
3 hours: 101
Nap
4 hours: 100
5 hours: 71

Anyone care to help me interpret? Anything odd?

I have heard that a workout can raise blood sugar a little if its not high when you start.
I’ll also mention that even at 5 hours I would have bet that I was still digesting my food. I was not hungery until about 7 hours after the meal. And I tested a few other times, and NEVER got anything like the 140 that I see some people getting after eating.

But my fasting level the next morning after about 10 hours was 97???

Anyone good with explaining blood sugar changes?

So basically, I wake up with a 90-100.

After breakfast, it DROPS for two hours to the 80s. Then it goes up to 100 for an hour, and then drops quickly to the low 70s. But at least after a night’s sleep it has crept its way back up to 90-100.

Why does it rise from say 75 to 95 overnight?

Could it be a sign of high cortisol levels?

I am as curious as you are. I’m sure there is a logical explanation. The question is what other sorts monitoring do you need to do to figure out what else is going on. I’ve been keeping an eye on my blood sugar recently to see the results of some dietary changes. My waking blood sugar is usually between 78 - 84, which is usually slightly lower than when I go sleep.

I think the strange part of your situation is not specifically that it rises overnight, but rather that you tend to revert to a high fasting glucose level. If I were in your shoes, I would keep a detailed daily log with the timing/contents of your meals, supplements and activities along with your periodic blood glucose levles. Go to doctor or a specialist with your data after a couple weeks and have them work you up.

The other interesting part of doing this is that it will allow you to do some dietary trial & error and see the impact it has. Over time, you can also see if there are any patterns that jump out at you.

Well, I had two possible hypotheses.

First I thought that the tests show that I have a pretty good insulin response, since my blood sugar goes down to the low 70s at 4-5 hours after a meal.

(I know that it rises very slowly after a meal, and in Europe they actually use just a 2 hour post meal blood test instead of fasting, with the same “danger zones” and I am in the 80s 2 hours after eating).

But that I am overtrained or have sleep apnea which may result in higher cortisol levels causing sugar to be pulled out into the blood, and or that I am not burning much at night.

The second, which I can test for is simply that I am dehydrated in the morning, so my blood is more concentrated. I can try to drink a little extra water before testing and see what that does.

[quote]mertdawg wrote:
Anyone good with explaining blood sugar changes?

So basically, I wake up with a 90-100.

After breakfast, it DROPS for two hours to the 80s. Then it goes up to 100 for an hour, and then drops quickly to the low 70s. But at least after a night’s sleep it has crept its way back up to 90-100.

Why does it rise from say 75 to 95 overnight?

Could it be a sign of high cortisol levels?

[/quote]

Not necessarily a definite sign of high cortisol; however, the reason why your blood glucose levels are higher in the morning is because of the counter regulatory hormones (epinephrine, norepinephine, cortisol, growth hormone, and glucagon) taking action in your body. These hormones have the opposite effect on insulin; ie. they work to release glucose from glycogen in the liver and stimulate lipolysis in order to raise glucose levels in the blood.

Without insulin, glucose and free fatty acid would increase in the blood because insulin isn’t present to shuttle these nutrients into the cell where they are utilized. Also, without insulin, more glucose would be made from protein.

Along with a little experiment of my own to follow-up on your results this morning, I also re-read your original post a couple times. My take is that you are concerned about the times in which your blood sugar seems to hover around 100… happened to be upon waking and 3 hrs post meal. Addressing the latter first, I think you were comparing blood sugar against the wrong variable in the 2nd case. While it may have been 3hrs post-meal when you got your 101, it is more significant that it was post-workout.

Unless you had caloric intake between the 2hr (87) and 3hr (101) readings, the only reason your blood sugar would rise is due to your body’s response to the workout. For what it’s worth, my blood sugar is elevated for several hours post-workout too. This happens to me with or without pre & post workout calories. I imagine this is due to several factors, some of which are described elsewhere on the site far more eloquently than I could. In this department, determining what is normal is oh so relative. On workout days, my blood sugar is almost always higher than non-workout days for the remainder of that night and does not go back to normal levels until the next day… granted we are not talking huge differences here, but since I have been tracking blood glucose I can see the pattern clearly.

The expirement I referred to in my first sentence was checking my blood glucose immediately upon naturally waking this morning (7:30). I usually check it before eating breakfast which is about an hour after waking on normal mornings. To my surprise, my glucose was at 97. I remeasured at 9am immediately before breakfast and I recorded an 84 which is a normal value for me before breakfast. So here again, it seems that natural hormonal variations that occur are probably responsible for boosting your blood glucose when you are waking sort of like what happens post workout, but certainly not in the same exact way. Serd’s first paragraph above seems relevant to me for both post workout glucose levels and waking glucose levels.

Yea, that’s what I’m experiencing basically.

Did another little experiment that I thought you would find interesting to test a brief workout’s impact on my blood glucose level. Here is the sequence:

3pm - BG was 93 - Still digesting lunch but BG is on the way down
3:15pm - Threw some extra calories on top via a Prolab LMM shake (400 cals)
4:05pm - BG down to 90 despite the shake 50 minutes earlier
4:20pm - BG down a bit more to 87
4:21 - 4:55pm - I do a quick Arms & Shoulder workout with average intensity
No calories of any type post immediately after workout.
5:05pm - BG jumped 11 points to 98.

I find all this very interesting. My post workout BG is typickally between 105 and 115, but that is after a PWO shake of Surge or whatever else is lying around. I never directly measured the natural rise in Blood Glucose before. Now I am curious what it would look like after a full blown workout. Today was purely an experiment, I was going to take the day off. Will measure again before I eat again to see how long it stays elevated.

Ok… took another reading at 6pm and blood glucose is down to 77. Hard to say when it started to drop, but my guess is about 20 minutes ago because I started to feel pronounced hunger. That usually doesn’t happen when my BG readings are above 90.

[quote]j77 wrote:
Ok… took another reading at 6pm and blood glucose is down to 77. Hard to say when it started to drop, but my guess is about 20 minutes ago because I started to feel pronounced hunger. That usually doesn’t happen when my BG readings are above 90.[/quote]

Thanks. I got similar results in two similar trials. Mice started to drop from a meal-peaked at just over 100. Workout out 2 hours post meal. It rose to 100 with a short workout, 110 with a longer more intense workout, but 1 hour post workout it was still 100 and then at 90 minutes 85 ish and 2 hours 75.

That means to me that insulin is active and sensitivity is up at about 1 hour post workout and that is probably a good time for some carbs.

I think I am going to start delaying my post workout shakes now instead of consuming immediately post-workout. This little glucose monitor is a very interesting contraption for getting real-time visibility of my body’s personal balancing act. I don’t have the scientific knowledge to expertly adjust my habits and intake timing… but there are a bunch of simple modifications I’ve made that have turned out to be rather helpful. Since everybody out there metabolizes things at different rates and is impacted by different variables, I believe it is a worthwhile effort to take a month or two and track what goes on in your body with your normal dietary intake and activities. I was definitely surprised by a few things. I may put together a post in a month or so of all my interesting and sometimes surprising findings that showed themselves during this excercise.

The only down side to undertaking this little project is sore fingertips from frequent testing (5-6 times on my busy experiment days). I am using 33 guage lancets which helps, but still. I don’t know how often diabetics are supposed to check their blood sugar, but this could definitely be annoying if I had to do it for a lifetime.

Young man you are doing just fine. I have been a type II for about eight years. I work very hard at getting my blood sugars down to your levels.

With your family history of sugar problems, it would be wise to really work on cutting the amount of sugar & alcohol you take in, and get the right amounts of fiber. Take your mutli’s, C. E, fish oil, ALA. I would say to do as I do, subscribe to Drwhitaker.com Health & Healing, and get his diabetic information.

If you should ever want to see a Registered Dietican, ask if they are diabetic, if not look elsewhere. If they ain’t diabetic, they cannot speak from experience. You will have to learn about walking/running after meals and a host of things muscle heads will scream are wrong, but they are not in danger of having “the sugars”. Picture diabetes as having sugar - pieces of sharp ice running through your body with the sharp edges making the 1,000,000 little cuts that lead to blindness, nerve damage, and more.

Take this with serious thought.