Can cats eat dog food? What happens and when it's a problem

Can cats eat dog food? The short answer

Dog food won't poison your cat. If your cat steals a few pieces from the dog's bowl, there's no need to worry. The problem is long-term feeding. Cats and dogs have very different nutritional needs: dogs are omnivores that can thrive on a varied diet, while cats are obligate carnivores that rely on nutrients found mainly in animal tissue. Dog food is formulated for dogs, so it may not contain enough of what cats need.

Why dog food isn't right for cats

Nutrient	Why cats need it	Problem with dog food
Taurine	Heart function, eyesight, reproduction, digestion	Cats can't make enough; many dog foods contain too little for cats
Protein	Cats need more protein than dogs	Dog food often has lower protein and more carbohydrate
Vitamin A	Cats can't convert beta-carotene from plants into vitamin A	Dog food may rely partly on plant sources
Arachidonic acid	An essential fatty acid for cats' skin, coat and reproduction	Dogs make their own, so dog food may contain little
Niacin (vitamin B3)	Cats need it from food	Levels may be too low for cats
Methionine and cysteine	Amino acids for coat and health	Cats need higher amounts

These differences are why pet food manufacturers make separate cat and dog foods, following separate nutritional guidelines.

What happens if a cat eats dog food long term?

Taurine deficiency

Taurine deficiency is the most serious risk. Over months, it can cause:

• Retinal degeneration: gradual, permanent loss of sight. Read about cat vision in can cats see in the dark.
• Dilated cardiomyopathy: a weakened, enlarged heart that can lead to heart failure.
• Poor reproduction and growth problems in kittens.

These problems were common before cat foods were properly supplemented with taurine. They're rare today, but can still happen in cats fed dog food, vegetarian diets or unbalanced homemade food.

Other problems

• Dull coat, dry skin and hair loss.
• Weight loss or muscle loss from too little protein.
• Vision and immune problems from vitamin A deficiency.
• Digestive upsets from a sudden diet change.

Obligate carnivores: why cats are different

Over millions of years, cats evolved eating small prey, which is rich in protein and fat and low in carbohydrate. As a result, cats lost the ability to make several nutrients that other animals produce themselves, including taurine, arachidonic acid and vitamin A from plant sources. They also use protein for energy all the time, so they need much more of it than dogs do. Dogs, which evolved alongside people and scavenged a varied diet, can make more of these nutrients themselves. That's the root of why a diet balanced for a dog falls short for a cat.

Can cats eat dog treats?

An occasional dog biscuit or chew won't harm a cat, though many are large, hard and not very appealing to cats. Some dog chews and dental sticks are too big and could be a choking hazard, and rawhide is hard for cats to digest. Choose treats made for cats instead, and count them as part of your cat's daily food.

A simple feeding plan for cats and dogs

Step	Cat	Dog
Where	Raised surface or a separate room	On the floor in another room
When	2–4 measured meals a day	1–2 measured meals a day
After eating	Pick up leftovers or use a microchip feeder	Pick up the bowl straight away
Water	Several bowls around the home	Fresh water in its own area

Consistency is the key: once both pets know their own meal times and places, food stealing usually stops.

Can cats eat canned dog food?

Wet dog food has the same nutritional gaps as dry. The meat content may look similar to cat food, but the overall balance of nutrients is designed for dogs. A spoonful won't hurt, but it isn't a substitute.

What to feed your cat in an emergency

If you've run out of cat food late at night, one meal of dog food won't harm a healthy adult cat. Better short-term alternatives include:

• Plain cooked chicken or turkey, without skin, bones or seasoning.
• Plain cooked white fish or tinned tuna in spring water (occasionally).
• Plain cooked lean meat, such as pork or beef. See our guide to whether cats can eat pork.

These aren't balanced either, so buy a complete cat food as soon as possible.

Why does my cat eat the dog's food?

• Opportunity: bowls left down all day are tempting for cats that like to graze.
• Taste and smell: some dog foods are strongly flavoured.
• Hunger: if your cat's portions are too small, it may look for more food. Check its needs with our cat food calculator.
• Competition: in multi-pet homes, some cats eat whatever they find in case food runs out.
• Illness: a sudden big appetite can be a sign of hyperthyroidism or diabetes in older cats.

How to stop your cat eating dog food

1. Feed at set times rather than leaving bowls down all day.
2. Feed pets in separate rooms and close the door.
3. Pick up the dog's bowl as soon as the dog has finished.
4. Feed your cat up high, on a worktop or shelf the dog can't reach.
5. Use a microchip feeder that only opens for the right pet.
6. Use puzzle feeders to slow down and occupy both pets.

Can dogs eat cat food?

Dogs often love cat food because it's higher in protein and fat. Occasional theft is usually harmless, but regular cat food can cause weight gain, stomach upsets and, in dogs prone to it, pancreatitis. Keep the cat's food where the dog can't reach. Dogs and cats also share parasites, so treat both: see our guide to whether dogs can get cat fleas.

Kittens and dog food

Kittens are even more vulnerable to the wrong diet, because they're growing fast and need extra protein, calories, calcium and taurine. Puppy food isn't a substitute for kitten food. If a kitten is stealing the dog's food, feed it more frequent small meals of a complete kitten food and keep the dog's bowl out of reach.

Signs your cat's diet isn't right

• Weight loss or weight gain.
• Dull, dry or greasy coat, or hair loss.
• Vomiting or diarrhoea.
• Lethargy or reduced activity.
• Changes in vision, such as bumping into things.

If your cat has been eating dog food regularly and shows any of these signs, see your vet. Blood tests can check taurine levels, and a heart scan can check for cardiomyopathy.

Choosing the right food for your cat

Look for a pet food labelled "complete" for cats at your cat's life stage (kitten, adult or senior). Complete foods contain everything a cat needs without extra supplements. "Complementary" foods and treats aren't balanced on their own. Wet, dry or a mix can all be healthy; many vets recommend some wet food for extra water. If your cat has a medical condition, your vet may recommend a special diet, such as a renal diet for kidney disease.