Final answer:
Normal fasting blood glucose levels for a 3-hour Glucose Tolerance Test should be between 60-90 mg/100 ml. The test requires a preparation involving a carb-rich diet for three days and 12-14 hours of fasting before ingestion of glucose. A non-diabetic person's glucose levels will return to normal within 2.5 hours, while a person with diabetes will show elevated levels.
Step-by-step explanation:
Normal Fasting Blood Glucose Levels for 3hr GTT
The 3-hour Glucose Tolerance Test (GTT) is a diagnostic tool used to evaluate how efficiently an individual metabolizes glucose, and it is particularly useful in diagnosing conditions like diabetes mellitus. For this test, normal fasting blood glucose levels should be between 60-90 mg/100 ml of blood. Proper preparation for the GTT involves maintaining a carbohydrate-rich diet for at least three days before the test, followed by 12-14 hours of fasting. The patient then consumes a specific dose of glucose, and blood glucose levels are monitored at regular intervals.
For a non-diabetic, the increase in blood sugar after consuming glucose will peak within an hour and will return to normal, or near the fasting level, within 2.5 hours. In contrast, a person with diabetes will experience a steep rise in blood glucose levels that does not return to normal within the same timeframe, indicating glucose intolerance.