Factors of life and eating habits: A large part of emaciation is caused by unscientific eating habits. Insufficient dietary intake, unreasonable dietary distribution, irregular diet, heavy pressure of study and work, anxiety, mental stress, excessive fatigue and poor sleep will all lead to emaciation.

Pathologically, digestive system diseases, tuberculosis, tumors, diabetes, hyperthyroidism, hepatitis, nephropathy and other diseases can cause weight loss; Chronic diseases, physical weakness and malnutrition can also lead to emaciation.

Due to physical and genetic factors, some thin people went to the hospital for examination and found no diseases. They can work normally on weekdays and have basically no discomfort. The emaciation of these people may be related to physical and genetic factors. For example, parents are thin and children are mostly thin.