Cats have sensitive stomachs and may become ill or stop eating if their food is changed abruptly. This can happen when a new food alters the intestinal environment, which may lead to diarrhea, vomiting and a refusal to eat—that’s why it’s best to gradually wean your cat off the current food and onto the new one.
Our friends at Purina recommend using the “1/4 every 4 days” rule:
- Add 25% new food every four days until your cat is completely transitioned to the new diet.
- Start by feeding your cat 75% of her current food and 25% new food for the first four days.
- On the fifth day switch to 50% current food and 50% new food for the next four days.
- By day nine you should be feeding 25% “old” food and 75% new for the following four days.
- In a little less than two weeks your cat will be fully transitioned to the new food!