diabetes supplement
Diabetes Testing

Why We Check Our Blood

With all the emphasis on how we check our blood glucose levels using all the new meters that we can choose from, many of us who have type 2 diabetes forget or never learned why we check our levels. Anyone who has type 1 diabetes has to know why he or she checks as do those type 2s who uses insulin. Those of us who inject insulin check their levels so they can take more if their levels are too high or take a glucose tab or something similar if they are too low.But three-fourths of all type 2s don’t take insulin. Some of them still use the first oral medication, one of the sulfonylureas that can cause hypos, a level below about 70 mg/dl. Then they too will need to take something like a glucose tab to bring their level back to normal.

The overwhelming majority of all people who have diabetes rarely if ever get hypos. So why should they go through the trouble of checking their blood glucose? What can they do with that information?

If our doctors and nurses ever told us why, most of us have forgotten by now. As a result, a lot of people with diabetes don’t bother at all any more with blood glucose checks.

That’s a shame, because even people who don’t use insulin or one of the sulfonylureas, can benefit from checking if they do it at the right time.

The most right time is after eating a big meal, especially one that has a substantial amount of starch in it. Nothing raises our blood glucose level as much and as fast as starch — the stuff in potatoes and grains and grain products, like bread, bagels, pizza, or anything made from wheat flour.

By general agreement the right time to check counts from the first bite of the meal. We have less agreement on how long after the start of the meal we should check, but most experts say that we should wait for two hours to check.

I wonder. The facts are that our levels generally reach a peak 72 or 74 minutes after the first bite, according to two different studies. In fact, if we would test even earlier, say at the one hour mark, we would be able to take corrective action even sooner. It’s your call, but my advice is whatever time you pick, be consistent from day to day.

People who have just learned that they have diabetes sometimes check their levels up to 10 times a day, like at sunrise, before and after every meal and snack, and at bedtime. That’s a good thing. But they can probably learn more about how their bodies handle carbohydrates by concentrating their checking on their heavy meals and then check every 15 minutes or so.

Many people seem to be concerned about the dawn phenomenon, where our levels are higher in the morning than when they go to bed. One of my articles here about it already has 94 comments. But the dawn phenomenon will, in my experience, disappear by itself when we generally control our diabetes.

In any case those levels don’t soar compared to those after heavy meals, and it is those high levels that we need to  avoid.When our levels soar, we can do something about them, even if we aren’t using insulin. What we can do  immediately about high levels is precisely the point of checking our blood glucose. We can get active.

I like to talk about activity, because for some of us “exercise” is a dirty word. In fact, it’s the very best thing that we can do to control our blood glucose level. As soon as we check and find out that our level is high after a meal we can take a brisk walk and bring it down to normal.

Just now I had a low-carb breakfast of bacon and eggs with a little fruit that boosted my level. Now I am going to leave you to walk it off.

This article is based on an earlier version of my article published by HealthCentral.

Never Miss An Update

Subscribe to my free newsletter “Diabetes Update”

I send out my newsletter on first of every month. It covers new articles and columns that I have written and important developments in diabetes generally that you may have missed.

Previous Post Next Post

You Might Also Like These Articles

  • David Mendosa at

    Fingerstick tests in any case only measure your level at one point in time. You need to get A1C test regularly to determine your level for the previous 2 or 3 months.

  • Arun at

    Dear Mendosa,
    They say hematocrit levels have an effect on the true value of blood sugar levels. In addition, dehydration can also show false low readings. Quite a few elderly tend to be dehydrated to some extent especially in the hot weather of the tropics, and of course in other countries as well.

    If dehydration and hematocrit values are variable and change from time to time, how does one get to know the true values of blood sugar while self testing?