What is an important pre-test dietary instruction for patients having a glucose tolerance test?

Fasting overnight is an essential dietary instruction for patients undergoing a glucose tolerance test because it helps ensure that baseline blood glucose levels are accurately measured. This test evaluates how well the body processes glucose and typically requires fasting for at least 8 to 12 hours prior to the test. By fasting, patients eliminate the influence of recent food intake, which could cause variations in blood sugar levels and potentially lead to inaccurate results.

Maintaining a balanced diet, avoiding sweets, or increasing protein intake may have implications for overall health and dietary management, but they do not directly address the requirement for standardized pre-test conditions needed for a glucose tolerance test. Hence, fasting overnight is crucial for obtaining valid and reliable test outcomes.