What do you think matters more

By luked Latest Reply 2012-09-17 02:05:44 -0500
Started 2012-09-14 05:25:46 -0500

What do you think - the absolute or the difference matters more?

What do you think is more important - the absolute BG readings or the difference between pre-prandial and post prandial readings? This question came up in my mind after reading some posts in the different diabetes related e-forums.

Here is an example:

Case 1: Pre-prandial 4.2 mmol/L (75 mg/dL) and post prandial 6.9 (125). Difference is 2.7 (50)

Case 2: Pre-prandial 6.1 (110) and post prandial 7.5 (135). Difference is only 1.4 (25)

Let us say the post meal readings noted above are the the peak readings after food and BG goes back to around pre-meal reading by 3 hours after food . Note that in both cases the BG levels remain below what is widely believed to be harmless levels.

My question is, which is better - Case 1 or Case 2?

Reading some of the posts in the various e-forums, I get the impression that the posters believe case 2 to be better. They seem to emphasize the difference between pre and post meal readings much more than the absolute BG readings. In a couple of posts it appeared to me that the posters were trying to relate A1c to the difference rather than the absolute levels.

My humble opinion in this matter is as follows:

1. Case 1 is better in spite of the difference between pre-and post meal readings being double of that in case 2. I believe the absolute BG levels are what matters and as long as the absolute level is within safe limits, we are safe.

2. A1c is determined by the absolute BG levels and not by the difference between pre and post prandial readings.

As I consume what I believe to be a reasonable amount of carbohydrates, I might see a difference of typically 2.7 (49) — my highest post prandial readings after a major meal are normally less than 7.4 (133) and pre-prandial readings are around 4.7 (84).

Tags: general

7 replies

annesmith 2012-09-17 01:55:50 -0500 Report

I think it depends. My mother, who is on insulin for type 2 diabetes, is always high, so , in "absolute" terms, if that exists, I'd say I would be worried about her constant highs. However, my dad and I were always brittle, and our blood sugar ranges were very erratic. So, for example , my blood sugar right now might be 100, but in 10 minutes it might be 299..typical for me, and was also typical for my dad. I'd say more damage can be done when the range is not consistent, because the blood vessels suffer terribly in the heart and organs, then. But, with a type 1 diabetic, who must have insulin to survive, they are in a chronic state of " the body will die soon" if they do not take their insulin. When you move from blood sugar reading A to blood sugar reading B, and the range is erratic and huge, the organ damage would be much more serious. But, when you are in an absolute state of " going to die" if you don't take your insulin, always severely high , I don't know—my strong opinion, and I could be wrong, is, if a person has inconsistent blood sugar levels that are erratic, this the worst…so, the difference matters the most. I am not a doctor or nurse…ha,ha…ANNE

Nick1962 2012-09-14 08:39:21 -0500 Report

Since any meter can be up to 20% off, and there are so many variables that lead to a single reading (type of food, time of day, etc.), there really is no absolute. The A1c is simply an average and will be the same whether your range is (case A) 20-170 or (case B) 70-120.
In either case, your A1c would be 4.8, but, not being a doctor myself, logic would tell me case B would be the far better scenario because the spread is far less and both high and low are away from the hyper and hypo “danger zones” for diabetics. Additionally, the smaller swing (even at elevated levels) indicates the body/pancreas is better responding at handling the food load. Wide swings create stress on the pancreas, and like any other body part, repeated stress tends to weaken it over time.

luked 2012-09-14 07:27:27 -0500 Report


I care about both the absolute (so that I'm in the non-diabetic range at all times and am not causing damage) and the difference (since it is indicative of how well I'm handling what I am eating).

In case 1, I would take a look at what I ate and if possible reduce carbs/protein or add more fat.

In case 2, I would be concerned that my BG doesn't return to normal non-diabetic numbers between meals.

If tweaking my diet didn't fix either case, and the spikes are over 140, I would consider adding/tweaking medication.

Just Joyce
Just Joyce 2012-09-14 12:11:59 -0500 Report

Meters vary so readings would be different for each reading. So if you have two meters and use them both, you would get a different reading on both. Glucose numbers vary based on food you eat, amount of food, exercise and activity so there isn't an absolute range. If you go for the absolute the non-diabetic range then I think you would be doing more harm than good. Even the doctor can't tell you the absolute. Each person and each meter is different so you can't say you have an absolute when I don't think it is scientifically possible.

I don't try to determine my A1C on a meter because the lab test could also be different. I prefer to let the lab do this.

jayabee52 2012-09-14 07:09:51 -0500 Report

Howdy Luke,

You use the "absolute" BG levels. Since our BG levels are constantly in flux, how does one determine an absolute BG reading? (inquiring minds want to know)


annesmith 2012-09-17 02:05:44 -0500 Report

This is Anne. I just thought of something. I am thinking that like when you listen to different parts of a song, any kind of music, you will hear parts of the song speed up, then slow down. The absolute would be the pitch and tone range from beginning to end—ha, I was once a music major. Each individual's diabetes is different, so, for example, I do know that even though I am brittle, I rarely hit over 600, and in a typical day, my range ( as erratic as it is) is between 180 and 400. So , my absolute is the interval between 180 and 400—-OH, boy, I also was once a math major—I'd better stop there—ha,ha…that's crazy what I just said in a way…ha,ha. It has some truth to it, but, really there is no absolute value for a diabetic—that'd be impossible—the absolute value in my strong opinion is the everyday range, not one number…if it were one number, the person would not be diabetic. Yeah, it'd have to be the everyday range. I'd be more concerned about the change from one number to the next, because I have been reading that the blood pressure , the heart, and the kidneys and the brain suffer more when the pancreas does not act consistently. ANNE