Vitamin C can enhance immunity, antioxidant, etc. Eating foods rich in vitamin C can supplement nutrients for diabetic patients. Vitamin C is a more important vitamin, is the human body indispensable vitamin, diabetic patients eat more food rich in vitamin C, can play the role of antioxidant, enhance the patient’s immunity, replenishment of nutrients and so on, such as kiwi, lemon, strawberries and so on. However, as a medicine, vitamin C can be used for the treatment of scurvy, can also be used for a variety of acute and chronic infectious diseases and purpura and other auxiliary treatment, etc., it is not recommended that diabetic patients take the drug by themselves. Patients diagnosed with diabetes are advised to cooperate with doctors for active treatment.