Constipation can be caused by weak gastrointestinal power, improper diet, intestinal polyps or intestinal tumors. 1. Weak gastrointestinal power: mostly seen in people who usually have less activities or the elderly, weak gastrointestinal power, slow peristalsis, food stays in the intestine for a long time, it will easily lead to constipation. 2. Improper diet: it may be because the diet is too fine, the intake of dietary fiber is relatively small, the volume of feces is insufficient and caused. It may also be due to dieting, resulting in insufficient production of stool caused by constipation. 3. Intestinal polyps or intestinal tumors: With the gradual increase of polyps or tumors, it is easy to lead to intestinal obstruction, thus causing constipation. Constipation may also be caused by other reasons, to improve diet and massage the abdomen to promote intestinal peristalsis, to help defecation, if the symptoms continue to be unrelieved, you should consult a doctor in a timely manner to identify the cause of targeted treatment.