People's blood sugar is constantly changing throughout the day, especially when eating. After we eat food, we digest it into glucose, and then it is absorbed into the blood to become blood sugar. It takes some time for food to be digested and gradually absorbed, so the blood sugar rises gradually after eating.
In general, blood sugar begins to rise after meals, reaching a peak between 30 minutes and 60 minutes, and then begins to decline. By 120 minutes, the absorption process is basically completed, and the blood sugar consumption time is entered. By 180 minutes, the blood sugar is basically close to the fasting level.
In this process, the peak of blood glucose absorption is between 30 minutes and 60 minutes, which can't be found accurately by general blood glucose testing, so we don't specifically detect the postprandial blood glucose peak at ordinary times, but it is certain that the postprandial blood glucose peak of normal people will not exceed11.1mmol/L.
But 2 hours after meal is a definite time point, and the blood sugar test at this point is meaningful, and the normal value is not more than 7.8 mmol/L; Similarly, the postprandial fasting blood glucose is 8- 12, which is what we call fasting blood glucose, and it is also helpful for us to judge the changes of blood glucose in a day, and the normal value is not more than 6. 1 mmol/L, which is why diabetic patients need to measure fasting blood glucose and 2 hours postprandial blood glucose in daily blood glucose monitoring.
By analyzing the changes of blood sugar in one day and the clinical significance of blood sugar at each time point, the diagnostic criteria of diabetes are determined as follows:
Fasting blood glucose is greater than or equal to 7.0 mmol/L.
2 hours after meal, the blood sugar is greater than or equal to11.1mmol/L.
The random blood glucose is greater than or equal to11.1mmol/l.
Therefore, if blood sugar is tested randomly, it depends on when it is measured. For example, the test after 40 minutes after meals is normal as long as it does not exceed11.1mmol/L, so don't worry.
In addition, it should be understood that the diagnostic criteria of diabetes mentioned above have been lowered in clinic, and a blood sugar range is also defined as pre-diabetes, that is, if you are in such a blood sugar range, although you can't confirm that you are diabetic, your blood sugar is abnormal, and you will soon develop into diabetes if you don't pay attention. The blood sugar range of pre-diabetes is:
Fasting blood glucose: 6.1-7.0 mmol/L.
Blood sugar 2 hours after meal: 7.8-11.1mmol/L.