The answer is as follows: Due to insufficient or underutilized insulin in diabetic patients, the body can't fully decompose glucose, so it can only supplement energy and calories by consuming fat and protein. Coupled with the loss of water, patients lose weight and lose weight. In severe cases, they will lose dozens of pounds, leading to fatigue and listlessness. Similarly, the longer the course of disease, the higher the blood sugar; The more serious the illness, the more obvious the weight loss.