The short answer is that a stolen mouthful of dog food will not poison your cat, but dog food is not a substitute for cat food, and a cat fed dog food as its diet will suffer for it over time. This is one of the clearest examples of why cats are not small dogs: they have specific nutritional needs that dog food is simply not designed to meet. So there is no need to panic if your cat pinches some of the dog’s dinner, but there is every reason not to rely on dog food to feed a cat.
Why cats cannot live on dog food
The difference comes down to what cats need as obligate carnivores, and dog food is formulated for an animal with different requirements.
Cats are true carnivores whose bodies are built to run on meat, and they need several things in amounts that dog food does not provide. They require more protein than dogs. They need vitamin A in a ready-made form, since unlike dogs they cannot convert it well from plant sources. They need arachidonic acid, a fat they cannot make themselves. And most importantly of all, they need taurine, an amino acid that cats cannot produce in sufficient quantity and must get from their diet. Dog food is not formulated to supply these at feline levels, because dogs do not need them the same way. So while dog food is not toxic, it is nutritionally inadequate for a cat, and feeding it long term sets a cat up for deficiency.
What to do about a food-thieving cat
If your cat keeps helping itself to the dog’s food, the answer is management rather than worry, and making sure the cat’s own food appeals.
Feed the animals separately so the cat cannot get at the dog’s bowl, which usually means feeding them in different rooms, or at set times and lifting the bowls afterwards rather than leaving food down. Then make sure your cat has a complete, balanced cat food that it actually likes and eats, since a cat that is bored of its food or not eating enough is more likely to go raiding. If your cat seems to prefer the dog’s food, is fussy, or is losing interest in its own meals, it is worth a word with your vet to rule out any underlying issue and to help you find a cat food that suits it.
So, can cats eat dog food? Not as a diet. An occasional stolen mouthful is harmless, but dog food lacks the taurine, protein, and other nutrients cats specifically need, and a cat fed dog food long term risks serious deficiency affecting its heart and eyes. Keep the pets’ food separate, feed your cat a proper complete cat food, and see your vet if your cat is going off its own meals. For the wider picture of feeding cats safely, see our guide to safe and toxic foods for cats.
Common questions
- Will dog food hurt my cat?
- A one-off mouthful of dog food will not poison a cat, so if your cat steals some from the dog's bowl there is no need to panic. The problem is dog food as a diet, since over time it leaves a cat short of nutrients it specifically needs, which can cause serious health problems.
- Why can't cats live on dog food?
- Cats are obligate carnivores with needs dogs do not share. They require more protein, plus taurine, vitamin A, and arachidonic acid in forms dog food does not provide in sufficient amounts. Most critically, cats cannot make enough taurine themselves and must get it from their food, and a shortage damages the heart and eyes.
- My cat prefers the dog's food. What should I do?
- Feed the pets separately so the cat cannot access the dog's food, for example in different rooms or by feeding at set times and removing bowls. Then make sure your cat has a complete, balanced cat food it will eat. If your cat is fussy or losing interest in its food, it is worth a chat with your vet.
