When should I stop drinking water the night before a blood glucose test?
Disease description:
I need to have a blood sugar test tomorrow. I'd like to ask the doctor, when tomorrow I have to measure my blood sugar, at what time in the evening can I no longer drink water?
Doctor's answer (1)
Dr. Bai Hongmei
Measure blood glucose the next day, and it is recommended to avoid excessive water intake after 10 PM.
To ensure the accuracy of blood glucose test results, it is necessary to follow certain guidelines. When preparing for a fasting blood glucose test, it is generally recommended to fast from midnight, which means no food or beverages, except water, should be consumed from 12 AM until the test the following morning.
The night before the blood glucose test, drinking small amounts of water will not significantly affect the test results. However, it is generally recommended to avoid excessive water consumption after 10 PM. This is because frequent nighttime urination may disrupt sleep quality, and poor sleep can in turn affect blood glucose levels the next day. Additionally, to obtain the most accurate blood glucose reading, it is advisable to avoid consuming large amounts of water—especially cold drinks—for at least one hour prior to testing, as this may temporarily affect blood glucose levels. Besides water intake, fasting blood glucose testing also requires approximately 8 hours of absolute fasting. The night before, excessive sugar consumption and alcohol should be avoided, a calm state of mind should be maintained, and vigorous physical activity should be avoided.
