A normal blood sugar range for an adult is less than 100 milligrams per deciliter when fasting for a minimum of 8 hours, or 140 mg/dL after eating, according to WebMD. Sugar levels are usually their lowest right before mealtime when nondiabetics' sugar levels are generally around 70 to 80 mg/dL.Continue Reading
What is considered normal for one person may not be normal for another. For example, for some people, readings of 90 mg/dL is a normal range, while for others, 60 mg/dL is considered average. Low sugar levels can vary widely as well. Some people never experience a blood sugar level lower than 60 mg/dL, even when they go without eating for a prolonged period.
When determining whether or not an individual has diabetes, doctors may perform several tests, including fasting plasma glucose tests, oral glucose tolerance tests and random checks. A fasting plasma glucose test is considered out of range if blood sugar levels exceed 126 mg/dL after an 8-hour fast. With an oral glucose tolerance test, diabetes may be indicated if sugar levels exceed 200 mg/dL after an 8-hour fast and 2 hours after drinking a special drink provided by the lab. Random blood sugar checks exceeding 200 mg/dL may also be indicative of the presence of diabetes.Learn more about Medical Ranges & Levels