Diabetic patients suddenly lose a lot of weight may belong to the abnormal phenomenon, may be abnormal blood sugar, hyperthyroidism, cirrhosis of the liver and other reasons, it is recommended to consult a doctor in a timely manner, to clarify the cause of the disease. 1. Abnormal blood sugar: diabetic patients with abnormal blood sugar, not enough insulin, can not fully metabolize glucose, the body lacks energy to consume fat, which leads to sudden thinning. 2. Hyperthyroidism: a small number of diabetic patients may suffer from hyperthyroidism, hyperthyroidism will lead to weight loss, hyperphagia, frequent bowel movements or diarrhea, resulting in sudden wasting. 3. Cirrhosis: Cirrhosis will cause a decrease in anabolic metabolism and an increase in consumptive metabolism, which will cause the patient to experience diarrhea and weight loss. When a diabetic patient suddenly lost a lot of weight, it is recommended that the patient go to the hospital in time, diagnosed by a professional doctor and given the appropriate treatment.