Wanting to have a bowel movement after drinking milk in the morning may be related to lactose intolerance, or it may be related to personal bowel habits, irritable bowel syndrome and other conditions. 1. Lactose intolerance: if every day after drinking milk, there is a clear feeling of wanting to poop, or with a slight diarrhea performance, generally consider the possibility of lactose intolerance, mainly in the lack of lactase enzyme in the population, unable to digest milk lactose and bloating, farting, diarrhea and other symptoms. 2. Defecation habits: if every day after breakfast, then the long-term may form a reflex defecation habits, every day will be regular defecation, in this case the quality and color of the feces is generally normal, does not belong to diarrhea. 3. Irritable bowel syndrome: people with irritable bowel syndrome may experience abdominal pain and diarrhea after eating. So after eating milk, you can also have the feeling of wanting to have a bowel movement. There may be other reasons for wanting to have a bowel movement after drinking milk in the morning, so you can go to the hospital to complete the relevant examinations to clarify the situation.