Lactose intolerance is a phenomenon caused by the body’s inability to break down the lactose in milk due to too little lactase production. Lactose intolerance is also known as lactase deficiency, and its symptoms are relatively numerous. Diarrhea: The main symptom of lactose intolerance is diarrhea, and many children may have diarrhea several times a day, and the stools are thin, egg-flake soup-like or foamy, and many children may vomit. Irritability: Lactose intolerance in some children can lead to abdominal distension, which can lead to varying degrees of emotional distress and crying, and the distension will improve with bowel movements or treatment. Colic: Generally, this symptom is most common in patients who have had surgery and are in the process of developing it, although some patients may have this symptom before they have diarrhea. The appearance of lactose intolerance is often directly related to the amount of lactose consumed, so it is important to feed your child according to the actual situation and the scientific way. Each time the amount should be controlled to an acceptable level, and then slowly and gradually added after adaptation.