Normal breakfast and dinner, bloating and diarrhea after lunch may be due to irritable bowel syndrome, dyspepsia, acute enteritis and other reasons. 1. Irritable bowel syndrome: because the morning study or work is more tense, the pressure is relatively large, so it induces irritable bowel syndrome leading to bloating and diarrhea after lunch, generally adjust the mood, relieve the pressure can be gradually relieved. 2. Indigestion: The food eaten at noon is more greasy, too much food is easy to cause indigestion, resulting in bloating, diarrhea, nausea and other discomforts. In this case, you can slightly reduce the amount of food at noon, adjust the diet structure, increase the intake of fruits and vegetables. Avoid eating too much gas-producing foods, such as soybeans. 3. Acute enteritis: The food eaten at noon is infected by bacteria or mold, which leads to acute enteritis causing abdominal pain, diarrhea, abdominal distension. You can use antibiotics and other drugs under the guidance of a doctor. Morning and evening meals are normal, after lunch bloating and diarrhea, it is recommended to consult a doctor in a timely manner to identify the cause of the early treatment under the guidance of a physician.