Food can’t lower blood sugar, but it can keep blood sugar stable through dietary control to avoid big fluctuation of blood sugar. Patients with hyperglycemia can lower their blood glucose through good dietary control, proper exercise, taking hypoglycemic drugs such as acarbose or insulin injection, etc. Therefore, food alone can not play a therapeutic effect of lowering blood glucose. However, good dietary control can play a role in maintaining blood glucose stability, such as controlling total calorie intake, maintaining a low-salt, low-fat and low-sugar diet, and eating some low-GI foods, such as corn, spinach, apples, cherries, etc., which will not cause large fluctuations in blood glucose. Patients diagnosed with hyperglycemia should actively cooperate with doctors for treatment and maintain a healthy diet.