Why Testing Only Once Per Day is Insufficient for Any Diabetic


Blood glucose testing is a pain, literally. One has to stick their finger or in the case of alternate site testing, other tender areas on the body to extract a tiny blood sample. Nobody likes to do it. It isn’t fun. It is, however, the most important step to managing your diabetes.

Because of the innate hassle of checking blood glucose at home, many diabetics who are borderline or just diagnosed try to get away with testing their blood sugar only one time a day. Most often first thing in the morning. This is a waste and tells you very little about the actual state of your blood sugar. Here are some reasons why testing 1x daily does more harm than good.


Confirmation Bias


Most often diabetics know when their sugar should be up. Because we are all human, we want our blood sugar to be in normal ranges when we test. Often subconsciously, we tend to test after fasting or exercise when we only test one time per day. We know this often ensures a “good” result, but unfortunately that test is not at all representative of actual blood glucose levels during the day. In fact, it can lead to under medicating and progress your type 2 diabetes significantly. It’s like having your head in the sand.


Law of Averages


Diabetes isn’t something you just fight in the morning. Your liver will release a small amount of glucose to get you going in the morning, and that can skew results. If you only test in the morning, your averages will be even more skewed. The more you test throughout the day, the better you will know how your sugar runs during and after different activities(including lunch and snacks). If you only test one time per day, you will never have a good idea of how your body reacts to these things and your averages won’t be accurate.


Blood Glucose Testing Inaccuracies


There is up to a 20% margin for error for each blood glucose test. Testing multiple times will help you anecdotally realize when you’ve previously had a bad or inaccurate test, and will cause this margin for error on your overall averages to decrease as you get more results. The mathematics is complicated, but think of each sugar test as a scatter plot. The more results you have the clearer the actual line appears in your results over time.


Insulin Injections


Often times people who must take insulin try to get by only testing once per day. This isn’t ideal. Any time you are taking medication that affects your blood glucose, it is a good idea to accompany that medication with a glucose test.

Often times one believes they can “feel” when their blood glucose changes. You probably can. However, you can’t feel it with any accuracy. When you believe you feel your blood glucose is up or down, you can never be sure. That is why it is so important to test. If your blood sugar swings wildly enough for you to actually monitor the change in your body it is even more vital to verify that result with an actual blood glucose test. Never rely on feelings when your life may be on the line. Low blood sugar and very high blood sugar can result in coma or death.


There are some steps one can take to reduce the glucose check hassle. Get a supplier that delivers to your door. Make sure your injector is capable of alternate site testing, and make sure your meter can easily review results and averages. This can reduce the pain and improve the convenience of blood glucose testing.

My suggestion is to test 4x a day before every meal and at bedtime. Mix it up and test after meals sometimes. It let’s you know what’s going on inside, and it’s the only real way of knowing what exactly your blood glucose is doing. Your blood glucose can be down below 60 and you will not feel it. TEST! TEST! TEST!

*The author of this blog is not a medical professional and this article does not contain professional medical advice. This blog is not intended to substitute for medical advice, treatment, or diagnosis. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of the contents of this article. If you think you may have a medical emergency, call 911 immediately.