Not fasting blood draws have an effect on some laboratory indicators, such as liver function, fasting blood sugar, etc., while there is no significant effect on tests such as glycated hemoglobin. You can ask your doctor about the specific requirements before the test. Liver function, blood lipids, blood glucose and other tests are greatly affected by diet, usually requiring fasting for 8 to 10 hours the night before. However, for tests such as glycosylated hemoglobin, fasting has little effect on the results. If patients undergo multiple blood tests on a single day, some of which require fasting and some of which do not, fasting is usually recommended to avoid multiple blood draws and to reduce the number of needle sticks. Patients can consult their doctor for detailed precautions before undergoing a blood test.