Normal blood sugar levels (non fasting) should not exceed 200 mg/dl. By contrast, normal glucose levels following a lengthy fast should not exceed 126 mg/dl.
Why the big difference between fast and non-fast?
Blood sugar levels normally rise sharply immediately after each meal. This occurs because the body converts carbohydrates into glucose very rapidly. Glucose levels re-stabilize after several hours of food abstinence. Thus, non fasting glucose test results are random, while fasting test results reveal baseline glucose levels. You can read moer about this in this post on blood sugar levels one hour after eating.
Consequently, fasting glucose tests are most useful as diagnostic tools; non fasting glucose tests are more effective as diabetic management aids.
Fasting glucose tests are typically performed at labs. However, non fasting glucose tests are easily self-administered multiple times each day. Accurate readings develop within seconds after a single drop of blood is exposed to pretreated test strips contained inside OTC test kits. This article on checking blood sugar levels yoruself goes over this topic in more depth.
This feature of non fasting glucose tests facilitates optimize diabetic management in several ways.
For instance, it is imperative for diabetics to distribute carbohydrate consumption evenly throughout daily meals. Rapidly ascertaining that certain food(s) trigger large glucose variations allows appropriate adjustments to be made as early as the next meal! Likewise, obese or sedentary patients may continuously monitor the effectiveness of weight loss efforts or lifestyle adjustments.
Indeed, precise identification of individualized normal of high blood sugar levels (non fasting) often permits total liberation from insulin or other diabetic medications. Potentially lethal diabetic complications can even be averted by regular non fasting blood sugar testing.
For example, a glucose level in excess of 240 mg/dl usually indicates immediate ketone urinalyses to identify the accumulation of dangerously high blood acid concentrations that mandate immediate medical intervention.
