No bowel movement during weight loss may be the result of excessive weight loss or a sign of constipation. 1. Excessive weight loss: eating too little will easily lead to less stool or a few days without bowel movement, if this is the cause of the appropriate more food will have stool, do not lose weight excessively, excessive weight loss will affect the health of the body, easily lead to malnutrition. 2. constipation: it may be lack of water, making the stool concentrated, resulting in less stool, or even a few days feel no stool, pay attention to a healthy diet, usually eat more fruits and vegetables. If the symptom of no bowel movement is not relieved, or accompanied by other symptoms, you should go to the hospital in time, and give targeted treatment after clarifying the cause.