Canadian Practical Nurse Registration Examination (CPNRE) 2026 – 400 Free Practice Questions to Pass the Exam

Fasting overnight is an essential action before undergoing a glucose tolerance test because it ensures that the results of the test accurately reflect the body's ability to process glucose without the influence of recent food intake. This preparation minimizes variables that could interfere with the test, providing a clearer picture of how the body manages glucose. Typically, patients are instructed to refrain from eating or drinking anything except water for a specific period, usually 8 to 12 hours, prior to the test. This allows for a baseline measurement of blood glucose levels and helps healthcare providers assess how well the body responds to a glucose load during the test.

The other choices are not appropriate as they could skew the test results. Eating a high-sugar meal would lead to elevated glucose levels, complicating the interpretation of how well glucose is processed. Drinking a high-calorie shake similarly introduces excessive carbohydrates, which would not reflect a fasting state. Increasing carbohydrate intake also contradicts the need for fasting, as it would raise blood glucose levels before testing. Therefore, fasting overnight is crucial for ensuring the integrity and reliability of the glucose tolerance test results.