Fasting blood glucose 3.1mmol/L is not normal, belongs to the low state. Under normal circumstances, the normal range of fasting blood glucose is 3.9~6.1mmol/L. If the measurement of fasting blood glucose value is 3.1mmol/L, the blood glucose is lower than the normal range, which belongs to the low blood glucose state. Since glucose is the main energy-supplying material of the body, low blood sugar may cause abnormal body functions and symptoms of hypoglycemia, such as panic, fatigue, sweating, dizziness, etc. If the blood sugar is further lowered, there may also be impaired consciousness and coma, so if the above symptoms occur, you should eat in time to correct the hypoglycemia, and to prevent the blood glucose from further lowering. If there is any discomfort, it is recommended to go to the hospital in time to get a clear diagnosis and targeted treatment under the guidance of the doctor.