When cats change their food, diarrhea is caused by their inability to adapt to the new food, causing gastrointestinal discomfort. You can reduce the proportion of new food and feed it with probiotics, which can effectively help the cat's digestion. Cats' gastrointestinal tracts are relatively sensitive. When changing food, it is best to choose hypoallergenic natural cat food, which has less gastrointestinal irritation. You can also add some cats' favorite snacks to help the cat adapt to the new cat food better.