Final answer:
The normal range for fasting glucose is below 100 mg/dL, with levels between 100 mg/dL and 125 mg/dL indicating pre-diabetes, and levels above 125 mg/dL indicating diabetes. Insulin regulation is key to maintaining blood glucose within the normal range.
Step-by-step explanation:
Normal Range for Fasting Glucose
The normal range for fasting glucose, which is measured after fasting for at least 12 hours, is below 100 mg/dL. A fasting blood glucose level between 100 mg/dL and 125 mg/dL indicates pre-diabetes, while a level higher than 125 mg/dL is indicative of diabetes. These values are important for diagnosing and managing diabetes.
Values That Indicate a Problem
A fasting glucose level less than 100 mg/dL is normal. However, glucose levels between 100 mg/dL and 125 mg/dL suggest pre-diabetes, a condition where blood sugar levels are higher than normal but not yet high enough to be classified as diabetes. A level exceeding 125 mg/dL after fasting is typically used to diagnose diabetes. Moreover, a glucose tolerance test (GTT) may be employed for further assessment, especially in cases where fasting glucose levels are within normal limits but there is a suspicion of diabetes.
Normal blood glucose levels vary depending on the time of measurement and the nutritional state—fasting (60-90 mg/100 ml), post-prandial (100-140 mg/100 ml after meals), and random (100-180 mg/100 ml at any time). Insulin plays a critical role in regulating blood glucose levels within these ranges.