The reasons why newborns refuse milk are as follows: a. Disease causes include weak digestive system, cold, thrush, etc., as follows: 1. Weak digestive system: The baby’s digestive system is weak, and it is easy for the composition of the milk, the low temperature of the water used to brew milk powder, and the cold in the abdomen and feet to cause indigestion, vomiting, diarrhea, and poor appetite. 2. Cold: The baby’s cold will cause the baby to feel suffocated during the milk intake due to nasal congestion. 3. thrush: If your baby has thrush, he or she will refuse to eat milk because of the pain. The reason for breast milk: If the amount of milk of the mother is too large, the outflow of milk during the baby’s breastfeeding process is too fast, causing the baby to choke and cough, and after repeatedly choking and coughing several times, the baby will be afraid to eat the milk and therefore refuse to eat the milk. If the mother’s milk volume is too small, the baby will have trouble sucking during the process of breastfeeding and is not full, resulting in irritability and refusal to eat the milk.