Many people in the usual outpatient clinic and in daily life complain of abnormal bowel movements: 1) more frequent stools, more than 3 times a day; 2) changes in stool characteristics: unformed, with or without mucus, pus and blood; 3) vague pain and discomfort around the belly button or lower abdomen; 4) a feeling of incomplete stool (feeling the urge to stool after the stool); 5) diarrhea when eating raw, spicy or cold food. There are many causes of the above symptoms, and the common possible clinical causes are: 1. IBS (irritable bowel syndrome): is a functional intestinal dysfunction, and is currently considered a functional disease. It is mostly seen in young patients. Before making such a diagnosis, gastroenteroscopy or barium meal gastrointestinal examination, upper abdominal ultrasound, liver and kidney function, blood glucose, and thyroid function (T3, T4, TSH) should be performed first, after which the disease can be considered if there is no obvious disease. In other words, this disease is a diagnosis of exclusion, so it cannot be made easily. 2. Non-specific colitis, which is a general inflammation of the colon other than inflammatory bowel disease (IBD). 3, specific colitis: mainly refers to inflammatory bowel disease (IBD), including ulcerative colitis, Crohn’s disease. 4.Colon polyps: there are multiple colon polyps, familial colon polyposis. 5, hyperthyroidism: the usual hyperthyroidism caused by the abnormal function of the gastrointestinal tract, once the hyperthyroidism treatment improves, gastrointestinal symptoms (diarrhea) will quickly disappear. 6.Colon cancer: Mostly seen in patients who are a little older. But clinically, we often find patients with colon cancer and stomach cancer around 20 years old. Therefore, if you have the above symptoms, it is best to seek medical attention for colonoscopy.