Normal Blood Sugar Range in Adults

According to the American Diabetes Association, 25.8 million Americans are diabetic. Another 7 million are diabetic but have not been diagnosed. And, 79 million are prediabetic, meaning they are at high risk for developing diabetes at some point in their lives. Knowing the normal glucose range and what your numbers are is the first step in protecting yourself from diabetes.

Testing Blood Glucose

A simple finger stick test using a very small drop of blood is all that is needed to check your glucose level. This should be part of your yearly physical, even if you have never had diabetes. Early screening allows early treatment. The most accurate measurement is a fasting blood sugar, preferably early in the morning before you've had anything to eat or drink. Your health-care provider will let you know how you should prepare for the test.

What the Numbers Mean

What Is Considered a High Blood Sugar Level for a Diabetic?

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A fasting blood sugar of 99 mg/dL or less is considered within the normal range. A person is prediabetic if fasting blood sugar is between 100 to 125 mg/dL. Diabetes is diagnosed at 126 mg/dL or greater. It's important to note that one high blood sugar does not automatically make you diabetic. Instead, your health-care provider will likely order follow-up glucose testing over the next few weeks to determine your normal range.

What if My Numbers are Elevated?

If your numbers fall into the range of diabetes or prediabetes after follow-up testing, your health-care provider will prescribe a plan of treatment. In the early stages of diabetes, if your glucose is only mildly elevated, you may be able to control it with diet and physical exercise on a regular basis. Being more aware of what you eat is an important step to controlling diabetes. You may find a food log helpful to pinpoint areas in which you can make better choices. Insulin and medication are normally used only after other measures have failed.

Exercise Tips

What Are the Blood Sugar Levels for Diabetes?

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Never begin an exercise program without your health-care provider's approval. The Mayo Clinic supports 150 minutes of moderate exercise each week, such as walking, swimming, or biking. Before exercising, check your blood sugar. If blood glucose is less than 100 mg/dL or greater than 300 mg/dL or higher, you should not exercise. For low blood sugar, have a small carbohydrate-rich snack, such as crackers or fruit. For high blood sugar, you are at risk of ketoacidosis and should wait until blood glucose drops. The ideal range for a workout is from 100 to 250 mg/dL. Always recheck your blood sugar following a workout.