The benefits of belly breathing are increased lung capacity and improved gastrointestinal motility. There are no significant harmful effects of belly breathing. The benefits of belly breathing include: 1. Increased lung capacity. Abdominal breathing is conducive to an increased degree of thoracic expansion, which makes the expansion capacity of the alveoli and gas capacity increase, thus contributing to the enhancement of cardiopulmonary function. 2. Promoting gastrointestinal peristalsis. During abdominal breathing, the pressure in the abdominal cavity changes, the blood circulation in the gastrointestinal tract increases, and the digestive capacity of the gastrointestinal tract is promoted to increase. At present, there is no literature research indicating that it has obvious harmful effects. If there is any abnormality in breathing, it is necessary to consult a doctor in time to clarify the cause of the disease, and the doctor will regulate the treatment according to different causes.