Blood Glucose Definition

Blood glucose is the main sugar found in the bloodstream. The body makes glucose from the food we eat. The primary function of glucose is to provide energy to the body's cells. Most people's bodies are able to regulate their blood sugar levels. For some, however, high blood-glucose levels are a sign of diabetes. When blood sugar is too low, a person becomes hypoglycemic. Without treatment, both of these conditions are potentially life-threatening.

Normal Levels

• The normal range for blood glucose, reports the American Diabetes Association, is between 70 and 100 milligrams per deciliter of blood (mg/dL). After eating a meal, a normal person could have a blood glucose level of up to 140 mg/dL.

Measuring Blood Glucose

• To measure the amount of sugar in the blood, a doctor will conduct a fasting blood sugar test. This means your doctor will test your blood eight hours after your last meal. Physicians usually order this test to diagnose diabetes.

Low Levels

• With hypoglycemia, your blood sugar drops below 70 mg/dL, and you will feel shaky and hungry, and will probably experience a quickened pulse. Once you eat something, these symptoms should dissipate. Blood sugar below 50 mg/dL could result in a seizure, loss of consciousness or decreased mental function.

High Levels

• A level of 110 to 125 mg/dL could indicate prediabetes. The American Diabetes Association states a blood glucose level of 126 mg/dL qualifies as diabetes.

Fluctuating Blood Glucose

• If your blood glucose rises and falls, it's important to figure out how to control your blood-sugar levels. Any number of diseases or illness can make glucose rise. Eating and stress also raise blood sugar. Exercise and medication help lower your glucose levels.