Normal Blood Sugar Range

It’s important to know what controls blood glucose levels and if you’re within the normal range. Why? Because if your blood glucose levels are abnormal, you’re at risk for diabetes or prediabetes. As you hopefully already know, the dangers of diabetes are particularly nefarious. This condition affects your eyes, heart, and kidneys, and can lead to blindness; amputations of fingers, toes, hands, or feet; kidney failure; and heart attack and stroke. Diabetes symptoms can be controlled to mitigate these dangers, but to control it, you have to know if you have it or not. And the best way to find out if you’re healthy is to get tested.

There are several testing times when a doctor may test. The two main ones are fasting (done six to eight hours after your last meal, so usually this test is done before you have breakfast in the morning) and postprandial (this means checking about two hours after a meal). These are the most straightforward times for diabetes testing to see if you’re within the normal blood sugar range.

However, you might also receive an oral glucose tolerance test. In this test, you fast overnight and then drink some sugar-water. The doctors then go about monitoring your glucose levels for a few hours; if you have diabetes or prediabetes, your levels will shoot higher and remain elevated for a longer period of time than they will for a healthy person. Finally, you may also receive a random blood sugar test, in which they test you several times throughout the day. This test is helpful because normal people’s blood glucose levels don’t vary that much throughout the day; but diabetics and prediabetics are less stable.

What is the normal blood sugar range? After fasting, a normal person will have glucose levels between 70-100 mg/dL; preferably 80-90 mg/dL to be within the ideal normal blood sugar range. A level above 100 mg/dL is usually the cutoff for prediabetes, which means you don’t officially have diabetes, but you’re at risk for it and should be careful. The definition of diabetic used to be a fasting glucose level above 140; but recently, the American Diabetes Association lowered that number down to 126 mg/dL.

After eating, a person will experience a mild spike in glucose, but usually won’t go above 120 mg/dL (maybe a little higher, depending on the food). Most normal people will go back to under 100 mg/dL after about two hours. Prediabetics may go as high as 200 mg/dL after eating; their glucose levels will remain elevated for a longer period of time, and may eventually drop below normal to fall as low as 50 mg/dL. This will cause symptoms of low blood sugar.

Low blood sugar (hypoglycemia) is anything below 60-65 mg/dL—below the normal range. It will cause nervousness, shaking, and hunger, especially for sweets. You may also experience some heart racing. High blood pressure (hyperglycemia) is the opposite. If glucose levels go above 200 or so (very high above normal), glucose may spill into your urine because your kidney won’t be able to reabsorb it all. High triglyceride levels may increase your risk of diabetes, according to some researchers.