Cats · Guide
Can Cats Eat Dog Food?
A few bites of dog food won’t hurt your cat, but it can’t be their regular diet. Here’s what dog food lacks for cats, and why dogs shouldn’t eat cat food either.
A bite or two of dog food won’t hurt your cat. Dog food isn’t toxic to cats, but it’s not made for them, and a cat who eats it as their main diet can end up missing nutrients they can’t live without.
The reason comes down to biology: cats are obligate carnivores, and their nutritional needs are stricter than a dog’s.
Why dog food doesn’t work for cats
Cornell’s Feline Health Center describes cats as obligate carnivores, meaning they depend on nutrients that only come from animal products. International Cat Care puts it plainly: cats can’t thrive or survive without meat.
Dogs are more flexible. Their bodies can make some nutrients from plant ingredients that cats simply can’t. The Merck Veterinary Manual notes that cats can develop nutritional deficiencies when fed diets formulated for dogs, and lists several specific gaps. AKC adds that dog food doesn’t contain enough taurine, vitamin A, arachidonic acid, or meat protein for cats.
| Nutrient | What cats need | Why dog food falls short |
|---|---|---|
| Taurine | Must come from food | Dogs don’t need it in their diet, and dog food lacks enough for cats |
| Vitamin A | Must be preformed (from animal sources) | Dogs can make it from beta-carotene in plants; cats can’t |
| Arachidonic acid | Must come from animal fat | Dogs can make it from other fats; cats can’t readily |
| Protein | Higher minimum | Adult dog food is formulated to a lower protein standard |
Taurine
Taurine is an amino acid that cats must get from their diet. Merck explains that plant proteins contain none of it, which is why cats need animal protein or added taurine.
Vitamin A
Plants contain beta-carotene, which dogs convert into vitamin A. Cats lack the enzyme to do that, according to Merck, so they need vitamin A that’s already formed, from sources like liver, fish oil, or a synthetic supplement in their food. A shortage can affect the eyes, including night blindness.
Arachidonic acid
This is an omega-6 fatty acid found in fat from meat, poultry, and eggs. Dogs can make it from another fat, linoleic acid. Merck notes cats can’t readily do that conversion, so they need it from food.
Protein
Cats need much more protein than dogs. International Cat Care explains that cats use protein as an energy source and can’t adapt to lower-protein diets the way dogs and people can. Merck cites minimum guidelines from the Association of American Feed Control Officials (AAFCO): 26% protein on a dry-matter basis for adult cats, compared with 18% for adult dogs.
Cats also need higher levels of certain B vitamins, like niacin, and the amino acid arginine, per Merck.
What happens with taurine deficiency
Taurine is the nutrient that matters most here. According to Merck, a lack of taurine can cause two serious problems in cats:
- Dilated cardiomyopathy, a disease in which the heart muscle gradually loses its ability to pump
- Retinal degeneration, damage to the back of the eye that affects vision
Before 1987, taurine deficiency caused most cases of dilated cardiomyopathy in cats. Once that link was discovered, taurine was added to all commercial cat foods, and the disease became much less common. Merck notes that the taurine-related cases still seen today tend to show up in cats eating noncommercial diets or commercial dog food.
Cats with heart failure from this disease can have severe trouble breathing as fluid builds up in or around the lungs. Merck describes the outlook as serious, though cats that survive long enough for taurine supplements to work (about 2 to 3 weeks) can do very well.
Call your vet if your cat has been eating mostly dog food and is breathing fast or with effort, or seems to have trouble seeing. Labored breathing in a cat is an emergency.
What about a little dog food now and then?
An occasional mouthful isn’t a problem. Cornell suggests keeping all treats under 10 to 15 percent of a cat’s daily calories, and stolen dog food counts toward that. The issue is only when dog food starts replacing cat food.
If your cat keeps raiding the dog’s bowl:
- Feed your pets in separate rooms, or put the cat’s bowl somewhere the dog can’t reach and vice versa.
- Pick up the dog’s bowl after meals instead of leaving food out.
- Make sure your cat is getting enough of their own food. Ask your vet if you’re unsure about portions.
Can dogs eat cat food?
The reverse is more common, since many dogs find cat food irresistible. AKC explains that cat food is much higher in meat-based protein than dog food, which may be why dogs love the smell.
A stolen bowl now and then usually causes nothing worse than vomiting or diarrhea, though that varies by dog. But cat food isn’t balanced for dogs. According to AKC, a dog that eats it regularly can develop stomach upset, obesity, or pancreatitis, a painful inflammation of the pancreas that needs prompt veterinary care. Signs include belly pain, a hunched back, weakness, loss of appetite, vomiting, diarrhea, a swollen belly, and fever.
Call your vet if your dog shows any of those signs after getting into the cat’s food.
Choosing the right food for each pet
The simplest fix is to feed each pet a complete, balanced food made for their species. Cornell recommends checking the label for an AAFCO statement saying the food is complete and balanced for your cat’s life stage.
If you share your home with both cats and dogs, it’s worth knowing which human foods are off-limits too. See our guides to foods that are toxic to cats and foods that are toxic to dogs.