Snacking on cat food won't do your dog any favors — here's why and how to ensure your dog eats a balanced diet

• Dogs require different nutrients than cats, and eating cat food regularly can make them sick.
• However, you usually don't need to worry if your dog eats a few bites of cat food here and there.

Most dogs aren't picky when it comes to food. They'll happily scarf down whatever tasty morsels they can find. But what if your hungry pup gobbles up everything in its path, including food meant for your other pets?

It's not necessarily harmful for your dog to sneak a bite from your cat's bowl here and there — though of course, your cat might not be too pleased to find their food bowl empty.

But feeding your dog cat kibble or canned wet food regularly won't meet their nutritional needs in the long run.

Why dogs should stick with dog food

Kibbles are kibbles, right? Wrong. Cats and dogs have different nutritional needs, so their food isn't interchangeable.

"Cat food has everything that a dog needs, but not in the correct balance. These imbalances could lead to severe problems, especially over time," says Dr. Adam Currier, a veterinarian at Fuzzy Pet Health.

For example, cat food typically has more calories, fat, and protein than dog food, Currier says. This is because cat food contains a higher meat content than dog food, and meat is calorically dense.

For example:

• Hill's Science Diet Adult 6+ Large Breed Dog Food: This dog food contains 353 calories per cup and is 18.7% protein and 13.7% fat.
• Hill's Science Diet Adult 11+ Indoor Chicken Recipe Cat Food: This cat food contains 398 calories per cup and is 34.7% protein and 20.9% fat.

Dogs need more fiber than cat food can provide. They also require a different blend of vitamins and minerals to avoid nutrient toxicity and deficiencies, Currier says.

Note: As carnivores, cats have evolved to tolerate high levels of fat and protein. But dogs have an easier time consuming multiple food sources and processing plant-based foods, like grains.

Will cat food make them sick?

It may seem like your dog has a digestive system of steel. After all, dogs eat all kinds of things they find inside your house and out of it — poop, grass, bits of trash, fruit, veggie peels, shoes, and even diapers. You name it, and a dog has probably eaten it.

But dog tummies are more sensitive than you might expect. After all, things you eat regularly, like avocados, chocolate, and grapes, can poison and even kill your dog.

Cat food can also be toxic in large amounts. Cats can handle more vitamin D than dogs, so cat food may contain more vitamin D than your dog's system can safely process. Excess vitamin D can lead to kidney failure and may even be fatal for dogs.

Note: According to the Association of American Feed Control Officials (AAFCO), commercial dog food should provide at least 0.0125 milligrams (mg) of vitamin D, but no more than 0.075 mg per kilogram (kg) per day. Cat food should provide at least 0.007 mg of vitamin D, but no more than 0.75 mg per kg per day.

Even so, a bit of cat food once in a while probably won't send your pup to the emergency vet — but if your dog eats a large quantity all at once, or on a regular basis, they may develop serious complications, such as pancreatitis.

Pancreatitis, which can result from eating high amounts of protein and fat, can sometimes be fatal.

Signs of pancreatitis in dogs may include:

• Vomiting
• Hunched back
• Diarrhea
• Appetite loss
• Lethargy
• Fever
• Bloated or tender abdomen

According to Currier, a steady diet of cat food can also cause a number of health problems, including:

• Constipation and other digestive issues from lack of fiber.
• Nutrient toxicity, a type of poisoning that can happen when your pet gets too much of a certain vitamin or mineral.
• Kidney disease, which can lead to kidney failure.
• Bladder stones, which can cause blood in the urine. While small stones may pass on their own, large ones may completely block urine flow and require emergency medical attention.

It's fine for your dog to sneak a nibble of cat food occasionally, but it's better if they get their treats elsewhere. Currier recommends treats that benefit your dog's dental health — in short, you may want to offer dental chews instead of leaving the cat bowl available.

Quick tip: If you're in a pinch because you've run out of dog food and can't get to the store, opt for plain boiled rice and boneless lean chicken or eggs instead of cat food.

What kind of food do dogs need?

Like humans, dogs have specific nutritional needs. So how do you ensure your dog's nutrition is up to par?

For one thing, a dog on a well-balanced diet should have a healthy, shiny coat, Currier says.

According to Currier, possible signs of a nutrient deficiency may include:

• Poor skin health, such as skin crusting or a dull coat
• Brittle nails
• Vision or hearing problems
• Uncoordinated movements

If your dog's diet consists mainly of dog food, there's likely no reason to call your vet when they gobble down a bowl of cat food before you can put it out of reach.

But if you notice a change in behavior or any of the signs listed above, consider making a vet appointment — just to be on the safe side.

Note: Every dog food bag should include a feeding guide for pet parents that includes recommendations based on your dog's target weight, Currier says. But you can always ask your vet for more specific guidelines, if you're unsure.

Other helpful tips:

• Feed your dog at least twice a day: Currier says it's also a good idea to feed your dog more than once a day, with twice daily being the most convenient schedule for most people.
• Feed puppies more frequently: Young puppies require more frequent, smaller-sized feedings, according to Jessica Sewell, VCA Animal Hospitals regional technician and assistant director. Your bag of puppy chow will also feature feeding guidelines you can follow.
• Change your dog's diet gradually: It's important to make a gradual change when switching to a new food. Your dog's system needs time to adjust, Currier says, so you'll want to mix the new food with the old food over a period of one to two weeks.
• Steer clear of grain-free dog foods: Evidence suggests that a grain-free diet may lead to heart problems for dogs, such as dilated cardiomyopathy (DCM). Dogs typically need grains as part of a balanced diet.
• Stick with a quality brand: "Some foods do contain higher-quality ingredients, so I typically recommend starting off with one of the name-brand diets like Purina One, Royal Canin, or Hill's," Currier says. However, he adds that you may need to experiment to find a brand that fits your pet.

If you have any questions about your dog's nutritional needs or the type of food you should feed them, a good next step involves checking in with your vet, Sewell recommends.

Popular advice you find online, like tips to feed your dog a raw food diet, may not always line up with what a qualified vet would recommend.

Latest research: One 2020 observational study involving over 3,600 dog and cat owners in the US, Canada, Australia, the UK, and New Zealand found that unconventional feeding practices, like feeding a raw food or vegan diet, can raise a dog's risk of nutrient deficiencies and health conditions.

How to keep your dog away from the cat food

Managing a cat and dog household can be tricky, especially when it comes to feeding times. Hungry dogs sometimes assume any and all food is up for grabs, including the cat's.

Here are some tips for discouraging your dog from getting into the cat's food:

• Place the cat food out of reach. If your dog hovers around your cat's bowl, try moving it somewhere your dog can't reach, like in a tall cat tree, inside a crate, on top of the dryer, or on a counter or desk. You might even try closing your cat in a room the dog can't get to, Sewell says.
• Get a special feeder for your cat. A device like the SureFeed Microchip Pet Feeder can prevent your dog from nosing around your cat's food, since this feeder will only open when your (microchipped) cat approaches.
• Switch to meal feeding. Instead of free feeding your cat, consider switching to meal feeding — feeding them at a specific time only — so you can keep a closer eye on your dog while your cat eats, Sewell suggests. Of course, some cats may not approve of this solution, so you may need to try other options for a cat who prefers to eat gradually.

Insider's takeaway

The occasional bite or stolen bowl of cat food usually won't harm your dog over the long term, but it's best to avoid feeding your dog an exclusive diet of cat food.

Not getting enough of the right nutrients — or too many of the wrong ones — can affect your dog's health over time, leading to conditions such as kidney disease or nutrient toxicity.

Carefully following the feeding guidelines on your dog's food bag can help ensure your dog enjoys a balanced diet. And if your dog loves the taste of cat food, strategically placing your cat's bowl somewhere your dog can't reach can help you keep both your pet pals happy and healthy.