Level 1: Causes of diarrhea caused by babies switching from milk powder to breast milk. Diarrhea may occur due to changes in intestinal flora and insufficient digestive adaptability when babies switch to milk powder or breast milk. In addition, improper formula of milk powder, incorrect feeding methods or poor sanitary conditions can also cause diarrhea in babies. Level 2: How to prevent diarrhea after babies switch to breast milk. In order to prevent babies from diarrhea after switching to breast milk, parents need to pay attention to the following points: 1. Gradual conversion: gradually add new milk powder or breast milk to the old milk powder or breast milk, so that the baby can gradually adapt. New diet. 2. Choose the appropriate formula: according to the child’s age, physical condition, etc.