Can Dogs Eat Tuna? Is Tuna Safe?

Written by: Bojana Radulovic
Should you serve tuna to your dog? Should this fish be a part of your dog's meal? Read on and discover.

Dog owners know that dogs are more than just in-house animals. They are family.

With family members, you get to share the right, the wrong, and everything in between.

Although there are some hard moments, there are much more good days, when you get to see those puppy eyes staring at you, wondering – Where is the food?

When it comes to families and food, one cannot ever be careful enough.

As treasured family members, dog owners are continually trying their best to provide dogs with what they need in terms of nutrition. This is why knowing how to feed your dog is important.

Choosing the best dog food is much easier when you know how to read pet food labels and when you have a trustworthy veterinarian who will help you be the best dog owner ever.

Knowing what your dog can and cannot eat is not only essential when it comes to overall dog nutrition, but it can also save your dog’s life.

This is something that is extremely useful when it comes to sharing human foods with your Fido.

If it were up only to dogs they would enjoy daily the majority of human foods, but that doesn’t mean that they should.

Some human food, such as cucumber is safe for dogs, and an efficient summer treat, while some like onion and garlic can lead to heavy poisoning and in some heavy cases even to death.

As you may guess, it’s crucial to know which table scraps are fine to be shared with your Fido, and which should be off-limits no matter what.

The big question here is, can dogs eat tuna? Let’s discover.

Can Dogs Eat Tuna?

If you are on the lookout for the short answer, the answer is yes – dogs can eat some sort of fish.

As for the tuna, you must be careful to feed them on properly-prepared tuna and serve only in safe moderation.

As a general rule, dogs shouldn’t eat any saltwater fish as it may lead to various health issues.

Commercial dog food usually contains some sort of fish, because it’s high in protein and omega-3 fatty acids.

Bear in mind that fish packed in dog’s commercial food is carefully used and mixed under supervision. Although tuna is rich in many nutrients, such as protein, magnesium, B vitamins, and omega-3 fatty acids, dog experts do not recommend tuna as a great snack for dogs.

Still, some experts claim that tuna can be served as an occasional treat as long as it’s served in special conditions, while others still talk about it as a big no-no.

Let’s see what are pros and cons and what you should have in mind when it comes to feeding your dog some tuna.

Is Tuna Safe For Dogs?

Before you introduce your dog to tuna (or any new food in fact) you should do proper research on that food item, and talk with your veterinarian first.

After all, your veterinarian should be able to provide you with non-biased information on any feeding style.

Veterinarians aren’t there only to conduct regular check-ups. Their job is also to educate you on how to provide the right care to your dog – make sure that you always have the best communication possible with your vet.

Now, let’s see what makes tuna so unique.


Did you know that mercury is a toxic metal that can cause many health effects if exposed to a significant amount it?

This is how too high levels of mercury react to people, but does that same effect mercury has on dogs as well?

It’s no secret that eating tuna in too high amounts can potentially lead to mercury poisoning.

Even if you don’t reach this state, you may experience some nausea, vomiting, and other health-related disturbances that may cost you your health and time, because no one wants to feel ill.

As for the people, their tuna intake should be limited. In most cases, doctors will advise people to limit their tuna intake according to their weight.

Are there identical guidelines when it comes to dogs? Simply said, no. There are no specific guidelines when it comes to mercury intake for dogs. However, it’s known that mercury poisoning may occur in dogs as well.

As such, mercury poisoning may harm a dog’s kidneys, nervous system, cardiovascular system, and even digestive tract.

All in all, due to the possibility of poisoning tuna should be served to your dog on extremely rare occasions and in extremely small amounts.

But… If your dog grabs a bit of tuna sandwich while you are not watching, should be ultra worried?

As long as he took a really small bite, he should be fine. That is, as long as the sandwich isn’t heavily packed with seasoning, such as garlic.

If your Fido ate an entire tuna sandwich or ate an entire tuna can, make sure that you contact your veterinarian.

As a general rule, if you suspect that your dog has consumed too much mercury, reach out to your veterinarian.

Why Is Tuna Toxic To Dogs? 

Again, the real possibility of mercury poisoning is what makes tuna so dangerous.

Both dogs and humans can experience mercury poisoning in a short period and suffer tremendously in the long run.

How can tuna be so packed with mercury? Well, tuna is a fish with a long life span, up to 40 to 50 years.

During that period they are often exposed to mercury when it enters the water area and accumulates in the ecosystem, including fish.

The longer a fish lives the bigger it gets, and contains more mercury. Now, imagine a fish of 50 years… It’s a long period to let mercury collect.

This is why you should be careful when it comes to fish in general. It cannot harm to know signs of mercury poisoning from tuna, because it may save your dog’s life.

Here are the most common symptoms of mercury poisoning in dogs:

  • Diarrhea
  • Vomiting 
  • Tremors 
  • Nervousness 
  • Difficulty urinating 
  • Abdominal swelling 
  • Poor coordination 
  • Blindness 
  • Hair loss  

These signs may occur when a dog ingests a high amount of mercury. If you notice any of the listed symptoms, make sure that you contact your veterinarian.

What To Do If Your Dog Eats Tuna

As mentioned earlier, as long as your dog grabs a small piece of tune, he should be fine.

On the other hand, if he eats a huge amount of tuna, you should monitor him closely and contact your veterinarian.

Tiny portions shouldn’t lead to any health-related issues, but a high amount of it can lead to mercury poisoning or any other health-related disturbance.

All in all, if you suspect that your dog are a significant amount of tuna, you should reach out to your veterinarian.

Can Dogs Eat Raw Tuna?

.This is a big no. Fresh tuna is packed with really high levels of mercury opposite to salmon and tilapia, let’s say.

Raw tuna can only lead to faster mercury poisoning. If you want to let your dog experience some fish, you should go for the safest option.

This means that you should aim for the fresh fish that is often used in dog commercial food, such as salmon, herring, whitefish, flounder, and Arctic char.

Again: before you make any new food introduction to your dog, make sure that you talk with your veterinarian first.

Are you a feline owner as well? If so, you should be careful when it comes to food.

Make sure that your cat’s bowl is high enough, or set it in another room because cat food is often packed with fish.

It’s common for wet cat food to contain tuna. Although a small amount of cat food should harm your Fido, still better to be safe than sorry.

Plus, cat and dog food shouldn’t be mixed, because nor a dog, nor a cat can get many benefits from eating each other’s food.

If you run out of dog food overnight, serving dry cat food may just trick your dog’s stomach that is full, but in reality, it won’t provide any of the health benefits that dogs (animals in general) should get through food.

Cats are heavy carnivores and they need a diet that is highly packed with proteins. However, although cats are mostly fish lovers, they may also be prone to mercury poisoning.

To avoid this, do your best to mix up cat food a bit, and serve wet food that contains not only tuna but a cat food made with other kinds of fish.

Can My Dog Eat Fresh-Cooked Tuna?

Although this sounds like a safer option, in fact, it isn’t. That being said, fresh-cooked tuna isn’t a great option for your Fido. This would be like serving him raw tuna.

Many believe that cooking decreases mercury but whether raw or cooked, the metal will still be there, because it’s tightly bound to the fish’s muscle tissue.

Can Dogs Eat Canned Tuna?

For humans, canned tuna is a great meal option. It’s affordable, has a fair amount of nutritional value, and is easy to mix with almost anything.

As a salad, or as wholemeal, it goes perfectly with anything, and during the whole year. Plus, it’s really easy to store it.

In most cases, canned tuna is meat from Albacore or Skipjack (with Skipjack being the safer option for your dog) species of tuna. However, no matter that small consumption of Skipjack shouldn’t lead to mercury poisoning, you should feed your Fido with canned tuna.

Canned tuna is packed with salt, just like pastrami, which isn’t suitable for dogs.

Salty food can lead to many health disturbances in dogs. Dogs cannot consume food that is rich in salt like humans do, and you should always avoid serving salty food to your dog.

Next to salt, canned tuna is packed with seasoning which is harmful to dogs.

Next to spices and salt, canned tuna is also preserved in different liquids, such as sunflower oil, and experienced dog owners know that food rich in oil can lead to obesity in dogs.

Obesity in dogs is a serious issue that may lead to various health issues.

Once you get a dog you’re directly responsible for his weight. To help your Fido have a long and healthy life, you should do your best to provide the following nutrition-wise:

  • To serve high-quality food
  • To learn to read pet food labels
  • To provide regular veterinarian check-ups
  • To know how much you should feed your dog
  • To know when to feed your dog
  • To know what a bloat is
  • To know which human foods are safe to share with your Fido, and which are a big no-no
  • To keep dog’s weight in balance

How Can I Prevent My Dog From Eating Tuna? 

Before you get a dog you should know that dogs are massive foodies.

Not only that they will enjoy a delicious meal, but they will love to have treats on regular basis. This is something that is easily seen when it comes to training.

As food-driven begins, dogs are easy to train as long as you have enough experience and great treats on hand.

When you know this, you know that keeping food far from their reach should be one of your biggest goals.

If you leave any food nearby, your dog will try to grab it. To prevent this you should be organized, knowledgeable when it comes to dog psychology, and creative when it comes to hiding dog food.

To keep your dog safe from unwanted food, your best solution is to keep that food away. This will be challenging, but most rewarding in terms of the health and longevity of your dog.

Store dry food somewhere where your dog won’t be able to reach out for it easily.

If you have a cat also, keep their bowl in different rooms, and close the door during the feeding time.

If your dog really loves cat food, supervise feeding time and try to serve your cat food that is packed not only with tuna but with other fish as well.

Let’s Recap

If your dog eats a tiny amount of tuna, he should be fine. However, if you grab an entire tuna sandwich, or eat an entire tuna can, make sure that you contact your veterinarian.

If you want to share a bit of tuna with your dog, make sure that you share the one that was canned in spring water.

Even this should be an extremely rare occasion, and never an everyday occurrence.

Remember that dogs will thrive on food that is specially designed for them, if you want that fish flavor to choose a commercial dog food that comes with fish flavor.