The number of bowel movements varies greatly among normal people, from 2 to 3 times a day to 2 to 3 times a week. In general, the amount of feces per person per day is 150 to 200 grams, which contains 60% to 80% of water. If the number of bowel movements increases (e.g., more than 3 times a day, the volume of feces increases (e.g., more than 200 grams a day), and the quality of feces is thin (e.g., water content exceeds 85%), it is diarrhea. Diarrhea can be divided into acute diarrhea and chronic diarrhea. Acute diarrhea is mostly seasonal, occurring in summer and autumn: chronic diarrhea is diarrhea that is recurrent or lasts more than two months. Diarrhea can be caused by many reasons, such as intestinal infection, indigestion, food poisoning, too little or lack of gastric acid, and the flow of food into the intestinal cavity after gastrectomy. Others, such as chronic pancreatitis, intestinal lactase deficiency, and lesions of the intestinal mucosa itself, can also cause diarrhea due to diminished absorption capacity. Diarrhea caused by gastrointestinal disease itself is the most common, but some diseases other than gastrointestinal disease may also cause diarrhea. The diseases that can cause diarrhea are roughly the following categories. 1, acute gastroenteritis caused by overeating. 2, eating unclean food caused by dysentery, cholera and other intestinal infectious diseases. 3.Intestinal allergy caused by eating allergic food. 4.Food or drug poisoning caused by eating toxic food or drugs. 5.Diseases of the stomach, pancreas and biliary tract. 6, ulcerative colitis caused by abnormal immune function. 7, functional enteropathy caused by mental and psychological factors, such as irritable bowel syndrome.