There are two symptoms of lactose intolerance as follows: 1. diarrhea, diarrhea is the main symptom of lactose intolerance, serious diarrhea can lead to more than a dozen times a day, most children have more intestinal gas during the disease, serious abdominal cramps, bloating or exhaustion, so defecation often brings out a small amount of stool, and the stool is mostly yellow and dilute, a small number of sick children will also appear back to milk or vomiting and other symptoms A small number of children show symptoms of colic, which often occurs during the course of the disease, but can also occur before the diarrhea, and patients with severe lactose intolerance may also show dehydration, acidosis, growth retardation and other phenomena.