Postprandial blood glucose can be measured after breakfast, lunch or dinner. At present, the main reason for monitoring postprandial blood glucose is 2 hours after meal, because current research has found that the relationship between postprandial blood glucose and microvascular and macrovascular lesions is the closest, and it is also directly related to the overall level of glycated hemoglobin. It is generally recommended that diabetic patients should monitor fasting plus 2 hours after three meals, for example, fasting plus post-breakfast blood sugar can be measured on Monday, fasting plus post-lunch blood sugar can be measured on Wednesday, and fasting plus post-dinner blood sugar can be measured on Friday, so that monitoring can probably understand the overall fasting blood sugar and the overall situation of post-meal blood sugar changes in a week, and will not increase the burden of patients because of too frequent fingertip blood sugar measurement.