Post Prandials

[zoelula]

I'm wondering if people do their post prandial blood sugar tests at one hour after eating or at two? I have thought that the standard was at two hours but if our peak is at one hour doesn't that mean that is when we should test in order to make sure we are in target? Damage can happen with any highs whenever they occur, so isn't the goal to find the time more likely to be the highest and test then?

[Josselyn]

Well, I test at about 1 hour and 15 minutes after my first bite for what is usually my peak BG level, if I'm monitoring closely. If I test at 2 hours, I'm checking to see if my BG has returned to "normal" although it often takes 2 hours 20 minutes to 3 hours for that to happen.

Yes, the highs matter, but so does the length of time our BG stays there.

[enigmalady777]

I generally do mine at two hours, but I have on occasion tested at one hour and one and a half hours.

It really depends on what I'm eating. If it's something new that I haven't eaten before and I'm not sure how to really dose for it (usually this happens when I go out to eat at a restaurant), I'll test at one hour and then again at two just to see what my levels are and to see if I'm spiking and when.

I find that if I spike really bad after one hour, my two hour test is also higher than I'd like. That's the point when I'll do a correction. Any sooner than two hours and I risk ending up with a nasty hypo (been there, done that, lol).

[mortis505]

Blood sugar spike will generally occur at approx 75 minutes pp. So a test at the 1 hour mark will not accurately show the spike since your levels will still be increasing.

Certain things can affect this spike in duration, such as fats, proteins, exercise, etc.

[DeusXM]

I have thought that the standard was at two hours but if our peak is at one hour doesn't that mean that is when we should test in order to make sure we are in target?

No, because most modern insulin analogues don't hit their stride until after the 1 hour mark. If you test at 1 hour and find you're running slightly high, and then take more insulin to compensate, you set yourself up for a world of hurt.

Also simply having elevated blood sugar doesn't necessarily cause damage. In a non-D, insulin is released when the body detects high blood sugar.

So having a temporary stage of high blood sugar is fine. That's why it's 2 hours for the PP test - the body needs to be able to return BG to normal levels within about 2 hours to avoid damage.

[zoelula]

Thanks, guys. Good point, that it is how long you stay high and if the insulin brings you back down within two hours that counts. I also wasn't thinking about corrections (I don't do them too often). If I was routinely testing at one hour it wouldn't be safe to correct then (and I don't get enough test strips to test at one AND two)

[Subby]

Assuming there are some carbs involved (or your food otherwise produces a spike of some sort...) I think one hour is useful and informative to find really bad 1 hour spikes. I don't like my spike to be too bad even if not for long, as rapid movement of BG can leave me feeling poorly and drained.

So, I see one hour testing as something to add at times you want to check what kind of spike a certain food or insulin timing etc might give you, to better "map" the curve of your BG trend from eating onwards. But - only in addition to the usual 2 hour to see how well the food/bolus combo is leaving you in the longer run.

[jenb]

I test at 1 hour for a couple of reasons. First, small doses of Novolog have a short duration of action; I usually use only 1.5 to 2.5 units for a meal. At 1 hour I can tell the direction my BG is heading and either add a little bolus or not. Second, it's a great way to test what the peak of glucose absorbtion is for carbs. If I'm adding a carb food that I don't normally eat it's a good way to test for it's effect.

I went for days testing every 15 minutes when I was trying to develop the least "peaky" breakfast. It was pretty interesting. For just about every food configuration and insulin timing, virtually all the glucose activity took place between 30 and 90 minutes post-prandial. I found that some foods like any hot cereal just caused too high a spike to be included in my diet, and that things like fruit had to be adjusted for quantity. My life as a lab rat!

Jen