Normal stool should be in the shape of bars and not like pellets. However, some people have habitual constipation, and their intestinal peristalsis is slow and food residues stay in the intestine for a relatively long time. Therefore, the intestinal system will excessively absorb the water in the food residue, and when defecating, not only will it be difficult to defecate, the nature of the stool will also be particularly dry and even granular. When irritable bowel syndrome is present, some people will experience diarrhea, but many will also experience constipation. During an attack of irritable bowel syndrome, the bowel movement is slow and the stool will take longer to pass, so the stool will be pellet-like. Bowel cancer is a malignant tumor, and this disease affects bowel function and therefore causes changes in bowel habits. Some people have constipation as the main manifestation, and the stool may even be granular, and some people may have mucus, pus and blood on the stool at the same time.