It is caused by irritable bowel syndrome, overly fine food, hemorrhoids, and intestinal tumors. The irritable bowel syndrome is triggered by more reasons, such as bad emotions, allergic food, overwork, some people in the attack to slow intestinal peristalsis, the nature of dry stool as a performance, the number of bowel movements will be relatively reduced, or even about three days once a bowel movement. If you are eating too finely or too little to produce food residue, the stimulation of the rectum will be weaker and the rectum will not be stimulated by feces, so you will not have the feeling of wanting to poop. Some people suffer from hemorrhoid disease, and because of the invasion of hemorrhoids during defecation, the patient will not want to defecate because of fear of hemorrhoid disease attack, but this idea will aggravate the hemorrhoid disease, and even lead to a vicious circle. The intestinal tumor is a malignant disease that affects the function of the intestines and consumes a lot of energy, which can lead to the disappearance of the body after the disease and changes in bowel habits, some of which are mainly constipation.