The clinical manifestation of coma is the loss of the wakefulness-sleep cycle, and the patient is in a continuous deep sleep and cannot wake up. The patient’s perception, attention, thinking, emotion, orientation, judgment, memory and many other mental activities are all lost. The patient does not understand himself or the external environment and does not respond to external stimuli. The patient is unable to perform simple commands. When given a strong painful stimulus, there is no conscious response at all, except for sometimes painful expressions or moans. What should be noted in the diet of patients with loss of consciousness? 1. The principle of dietary treatment for comatose patients is to control the total energy and protein and reduce the metabolic production of ammonia in the body. The energy supply should be appropriately controlled, with a daily supply of 6.7 MJ of dietary therapy principles for hepatic encephalopathy. 2. For coma patients, the daily protein supply should be controlled at about 0.5g/kg/person, and then the supply should be adjusted every 2~3d, but the maximum limit should not exceed 1g/kg/person. If there is an increase in blood ammonia and neurological symptoms at the same time, animal protein should not be given within 2~3d, and the supply should be adjusted every 2~3d from 0.2~0.3 g/kg/person onwards. For patients suffering from renal insufficiency or hepatorenal syndrome, protein intake should be strictly limited, especially animal protein. 3.The amount of fat in the diet should be 30~40g per day. In order to prevent the supply of insufficient caloric energy, fat emulsifier can be used, which can not only improve energy but also prevent diarrhea. 4, vitamin supply should be sufficient, especially the supply of vitamin C should be more, in order to facilitate detoxification. Low-protein diet often leads to a lack of calcium, iron, vitamin B2, vitamin K, etc., which should be supplemented outside the diet. Studies have shown that copper and zinc in the brain are reduced in liver failure, which may be one of the causes of liver coma, therefore, attention should be paid to the supplementation of zinc and copper in dietary treatment. 5. The supply of water and salt depends on the presence or absence of ascites and edema. If there is ascites or edema, a low-salt or salt-free diet should be given and fluid should be restricted.