Fasting blood glucose of 5.3 mmol/L is normal, and the normal fasting blood glucose value for a normal person is 3.9-6.1 mmol/L. 1. Fasting blood glucose refers to overnight fasting, the blood glucose value measured before breakfast, is the more commonly used blood glucose measurement indicators. The normal fasting blood glucose value is 3.9-6.1mmol/L. Fasting blood glucose is greater than 6.1 and less than 7.0mmol/L or 2 hours after the sugar load blood glucose is less than 7.8mmol/L to consider impaired fasting blood glucose. Diabetes diagnostic criteria involve a fasting blood glucose greater than or equal to 7.0 mmol/L. Hypoglycemia is considered when blood glucose is less than 2.8 mmol/L. 2. Everyone’s blood glucose fluctuates depending on diet, activity and other factors. Generally, the fasting blood glucose level is relatively constant, and the blood glucose concentration is regulated by the nerves, body fluids and other factors to keep it at a stable level; once these regulations are out of balance, hyperglycemia or hypoglycemia will occur. When fasting blood glucose is abnormal, it is necessary to consult a doctor in time and take active treatment, so as to avoid delaying the condition.