Why test 2 hours post meals?

[corwin]

Hi everybody,

I'm starting to get from the initial shock of being diagnosed to the routine of living with diabetes and of course more questions are poping.

I still don't understand why everybody is saying I should test 2 hours after I eat. I've had 171 2 hours after a meal which went to 207 2 hours after that. On the other hand I had 90 2 hours after a meal and I went hypo 30 minutes later (no idea how low I got). It seems like the 2 hours test don't give me any decent indication how I was effected by the meal.

I've had comments about this already and from what I was told, the reason I need to do it is to figure out if I should bolus more or I'm going too low, but how can 2 hours test tell me this if it keeps changing?

Thank you guys.

[seacomp]

but how can 2 hours test tell me this if it keeps changing?

The 2 hour post meal test attempts to capture the highest BG from the previous meal. The 2 hour figure is just a guesstimate of when the BG will hit its peak. It varies by person and by meal.
For your two cases, the first likely represents a fast-acting all carb meal; the second, a meal with significant protein and fat which stretches out the time of food absorption.
As you test and gain experience, you'll get to know these differences and make the proper adjustments.
Ain't no magic here, just work, experience and thought.

[vrocco1]

Do you have a target for the two hour reading? Reaching a target is one good reason to test.

[Cinnabon]

Exactly what everyone states her. Also, High fat foods will make your BSugar continue to elevate after the 2 hr mark. After the 2 hrs your BSugar should be start coming down.

[Cyborg]

Plus it gives you time to react to what might be coming. In your case of seeing a bg of 90 2 hours after eating, that should alarm you of a possible impending low since your insulin is not yet used up. Personally, I would eat something or take some glucose if I got a 90 at that time. At the very minimum, I would start checking every hour for next few hours (not fun).

[Cinnabon]

In your case of seeing a bg of 90 2 hours after eating, that should alarm you of a possible impending low since your insulin is not yet used up. Personally, I would eat something or take some glucose if I got a 90 at that time. At the very minimum, I would start checking every hour for next few hours (not fun).
Im sorry to diagree w/ you here...
I get 90s 2 hrs after and have stayed there . I always test at 3-4 hrs before bed and its the same. Dont know if its just the pump or maybe the food that I have eaten.

[Cyborg]

Im sorry to diagree w/ you here...
I get 90s 2 hrs after and have stayed there . I always test at 3-4 hrs before bed and its the same. Dont know if its just the pump or maybe the food that I have eaten.

I find that a bolus of Novalog will affect me approx 3 - 5 hours when my basals are set correctly. So if I check at 2 hours, I know there is still "insulin on board" that has not worked into my bg reading. At least that's my experience. Now if I check around 3 hours and get a 90, I feel more comfortable.

[psilocybin]

I find that a bolus of Novalog will affect me approx 3 - 5 hours when my basals are set correctly. So if I check at 2 hours, I know there is still "insulin on board" that has not worked into my bg reading. At least that's my experience. Now if I check around 3 hours and get a 90, I feel more comfortable.

it also depends on what u ate...some foods will cause you to rise after the 3 hour mark...each food acts differently

[corwin]

Thanks for the great info guys.

Cyborg I will take your advice next time and if I'm 90 I'll eat something. I'm not yet at a point where I know that I won't go lower and hypo isn't fun.

I finally managed to keep my bg levels between 110 and 162 for a whole day yesterday, I'm really happy I was able to do it. A lot of it thanks to the great advice I got in this forum.

[seacomp]

I finally managed to keep my bg levels between 110 and 162 for a whole day yesterday, I'm really happy I was able to do it.
It's good to hear that you're making progress!

[Cyborg]

Thanks for the great info guys.

Cyborg I will take your advice next time and if I'm 90 I'll eat something. I'm not yet at a point where I know that I won't go lower and hypo isn't fun.

I finally managed to keep my bg levels between 110 and 162 for a whole day yesterday, I'm really happy I was able to do it. A lot of it thanks to the great advice I got in this forum.

If you don't want to gain weight, pop a few glucose tablets when that happens rather than eating food. Insulin is known as a "fat drug".

If I were to get a 90 at 2 hours after eating a meal, I would interpret it as one of two things: either I over-bolused from an incorrect carb count or from an incorrect insulin to carb ratio. The carb count can be checked by eating preboxed, canned, jarred, etc., food that has accurate carb counts for you. This can help you to adjust your insulin to carb ratios.

[rzrbks]

If I were to get a 90 at 2 hours after eating a meal, I would interpret it as one of two things: either I over-bolused from an incorrect carb count or from an incorrect insulin to carb ratio. The carb count can be checked by eating preboxed, canned, jarred, etc., food that has accurate carb counts for you. This can help you to adjust your insulin to carb ratios.


Don't forget that physical activity can also have a HUGE effect on B/G readings.

I know that if I have done much activity in the 2 hours spand after eating, quite frequently I will have 90/5 or lower reading, but, if I have a rest when running low, I often will bounce back up to "normal."

Although, sometimes I do actually have eat a little more:bawling:

[Rhino]

I have to say that I honestly only feel comfortable testing every hour on the hour every day. It's not that I'm that brittle, or out of control, but it just gives me peace of mind to know exactly where my BS is at all times.

I allow myself to stay in the 80-120 range. 20 more or less is also just acceptable, so I really allow a range from 60-140. Anything outside of that I treat instantly.

I WILL NOT eat if my blood sugar is above 80. Preferably I like to be about 60 when I eat, as I know after one hour (proper bolus of course) I will spike about 50-60 points, and after the two hour mark, I end up around 90-100. Usually after the full 5 hour run of the insulin I'm hanging right around 70 or so, which is right where I like to be premeal again, and by then it's usually time to eat. My meals almost ALWAYS (No matter whether breakfast, lunch, or dinner) involve a bit of whole grain, a bit of legumes, and a bit of meat (usually fish, raw)

Now this is what works for me though, to avoid the really bad 2 hour spikes. I also know that ANYTHING I eat in the AM will make by BS spike as much as 100 points, so I usually try to not eat until I've been up for at least 4 hours, so I'm not a big breakfast guy.

P.S. Psilo - You liking Oblivion? This weekend I only got up from my PC to take care of diabetic stuff....

[DeusXM]

I also know that ANYTHING I eat in the AM will make by BS spike as much as 100 points, so I usually try to not eat until I've been up for at least 4 hours, so I'm not a big breakfast guy.

Chicken and egg scenario here. The reason your BG raises in the morning is because your body's got so used to you not eating that your liver goes mental into pouring out glucose into your blood to give you a bit of energy. I forced myself to eat breakfast in the mornings despite the fact I didn't feel like it, and after about a week of doing that, my wake-up bg suddenly dropped dramatically. Instead of waking up with a FBS of 8 or 9, I was waking up at 4.0-4.5.

Best thing I ever did in terms of my control was start eating breakfast again. Helps keep my BG level throughout the day.

Incidentally (and I know this is your routine and it works for you so yes, I'm meddling and I'm sorry), judging whether or not you can eat based on your BG is really bad way to manage your diabetes generally. Eat when you're hungry, regardless of your BG. If you're hungry that's because your body needs something from your food. If you're really worried about spiking after a meal, then just bolus more insulin. That's what it's for.

[Shotokan]

I won't eat before my BG comes down either. Here is a snippet from John Walsh's new edition of Pumping Insulin:

13.6 Clever Pump Tricks
How Long To Wait Before Eating
From Pumping Insulin, 4th Ed. © 2006 Diabetes Services, Inc.

If your premeal blood sugar is near your target and you have no excess insulin on board, how long after you take your meal dose should you wait before eating? Wait one minute for every 3 grams of carb you plan to eat. For instance, for 30 grams a 10 min. wait (30 grams/3 = 10 min.) is sufficient, while for 90 grams (90/3 = 30 min.) a 30 min. wait would be better. When having more than 60 grams, eat 15 or 20 grams early to offset the larger bolus you will be taking.

If your premeal reading happens to be high, add another minute for every 3 mg/dl you are above 100 mg/dl (or 6 minutes for every mmol above 6) to get the total number of minutes to wait before eating. For instance, if your blood sugar is 190 mg/dl, add another 30 min. (190-100/3 = 30 min.) to reduce postmeal spiking.

Wait time = grams/3 + (current BG - 100)/3

Just don’t forget to eat! Delayed eating is the most common cause for severe lows, so always set a reminder alarm to be sure you eat on time.

[corwin]

This seems close enough to be in the same thread.

I saw an old thread about target bg levels 2 hours post meal. It seems like most people try to stay in a certain range even with the rapid insulin and carbs still in the system. I thought that as long as the carbs and the insulin cancel eachother and I end up balanced I'm good. Do I also need to worry about it getting high before the insulin ends? If my target is 90-140 is it a big deal if 2 hours post meal it's 180 even if 4 hours after the meal it's back to 130? Should it be calculated according to amount of fat that slows the carb absorbtion?

I had a small meal which had only fast carbs 2 days ago, I beleive I caculated the carbs correctly but I was having a hypo 2 hours later. I was 85 which I know many of you don't consider hypo but it seems like my body is so used to high bg that I felt like I was hit by a truck. Could it be because I'm on my honeymoon period (I'm starting to suspect I am, not sure though), the fast carbs were naturally lowered while the insulin kept working?

So many things to learn.

Thanks in advance.

Corwin.

[BriOnH]

Best thing I ever did in terms of my control was start eating breakfast again. Helps keep my BG level throughout the day.



This is so true for me too, I hate it though. I never been a breakfast guy (unless it's the weekends and its brunch), and hate eating breakfast. I can get away with not eating breakfast and just taking a unit or two to compensate for the liver dump, but eating helps more to control swings in bg readings throughout the rest of the day.

As far as two hour testing after meals, I must admit that I don't pay as much attention to it as I should. I'll almost always get up to 240(13), but come right back down an hour or so later.