The child has weak gastrointestinal function and weak spleen and stomach. It is suggested that they should not eat too much at a time, pay attention to the combination of dietary fiber and meat and vegetables, and eat more fruits and vegetables. There must be a reason why the child suddenly lost his appetite. First, it depends on the child's daily excretion, second, whether there is something indigestible in the food recently eaten, and third, whether there is physical discomfort. If the above situation occurs, they can adjust their diet and carry out diet therapy, such as a small amount of hawthorn.