A one-year-old baby spitting up may be caused by indigestion, acute gastritis, gastrointestinal colds and so on. 1. indigestion: because the baby is relatively small, the digestive ability is still relatively weak, if the baby is allowed to eat too much milk or eat cooler milk, it may cause indigestion, causing spitting up, loss of appetite and other symptoms. 2. Acute gastritis: most of them are due to the baby eating unclean or unintentionally lead to bacterial infection, often also feel abdominal pain. 3. Gastrointestinal colds: most often seen in viral infection symptoms, mainly in the digestive tract symptoms, can be manifested as vomiting, abdominal pain, abdominal distension, diarrhea and other symptoms. One year old babies spitting up may also be due to other causes, such as intestinal torsion, should take the baby to the hospital in time to identify the cause of targeted treatment.