While it's not toxic or harmful for dogs to eat cat food on occasion, it's not recommended as a regular part of their diet. Cat food is formulated to meet the nutritional needs of cats, which are different from the nutritional needs of dogs. Cat food tends to be higher in fat and protein than dog food, and it may not provide all of the essential nutrients that dogs need to stay healthy. Additionally, if a dog eats too much cat food, it can lead to weight gain and other health problems.