Fasting blood glucose 7.9mmol/L is high for normal people; for diabetic patients it is over the control target range and is also elevated. 1. The normal value of fasting blood glucose for normal people is between 3.9~6.1mmol/L, so fasting blood glucose 7.9mmol/L is on the high side, and it is recommended to consult a professional physician for a clear diagnosis. 2. For patients who have been diagnosed with diabetes in the past, the general fasting blood glucose should be controlled between 4.4~7.0mmol/L, so the fasting blood glucose of 7.9mmol/L has not reached the control target, and it is recommended to consult a professional doctor to adjust the treatment plan. Once the blood glucose level is found to be elevated, it is recommended to consult a doctor in time. Patients with abnormally elevated blood glucose need to control the total calorie intake of food in their life, with appropriate exercise and regular monitoring of blood glucose.