What Will Happen If You Offer Your Dog Some Tuna?

What Will Happen If You Offer Your Dog Some Tuna?

Author WDF Staff | Last updated: Jun 17 2023


Many dog foods include fish. Fish is a healthy protein source and packed with omega fatty acids that are really beneficial for dogs and humans. One of our favorite fish dishes is tuna. We prepare it differently, and it is one of the most popular fish meals you can get.

If you are a dog owner, you probably noticed your dog wants a bit of your food. They don’t really care what you’re eating as long as you share with them. The same goes for tuna. However, before you give your dog some tuna, you should ensure you know the answer to the question, “Can dogs eat tuna?”

When it comes to giving your dog tuna, it would be best to avoid it. The answer to “Can dogs eat tuna?” should be - probably not. Giving tuna to dogs can lead to some health issues. Tuna is different than the rest of saltwater fish, and there are far healthier and more beneficial options than giving your dog tuna.

Is tuna good for dogs?

Tuna for dogs is a highly debated topic. Owners, vets, and nutritionists often disagree on whether dogs can eat tuna. Some vets claim that tuna’s benefits outweigh the potential issues a dog might get from eating tuna. Not only is tuna an excellent omega fatty acids source, but it is also high in protein and vitamins. Technically speaking, tuna can be good for dogs.

Protein is the base of any healthy dog diet, and omega-fatty acids are great for dogs’ bones and joints. Omega fatty acids have some anti-inflammatory properties, so dogs with arthritis should consume more omega-3 and omega-6 fatty acids.

There are different supplements rich in omega fatty acids your dog could take. Check out this article - Fish oil for dogs.

Is tuna bad for dogs?

Unfortunately, eating tuna fish has a negative side - for dogs and humans alike. Tuna is a large fish, and because it can grow so large, there is more time for the fish to absorb mercury. The biggest issue with dogs eating tuna is mercury poisoning. It is not the only issue but undoubtedly the most dangerous one.

1. Mercury poisoning

Mercury is a byproduct of many industrial activities, and one of them is coal-powered plants. The mercury is dumped in rivers and lakes, where it flows to the ocean, and fish absorb them. Large fish like tuna have more chances of absorbing this poisonous metal. Since it is one of our favorite meals, we can easily ingest mercury by eating tuna.

The same goes for our dogs. If you feed a lot of tuna to your dog over a long time, it can lead to mercury poisoning. That is one of the key reasons why it would be best to avoid feeding your dog tuna, especially raw.

tuna steak

Mercury poisoning can be deadly. If your dog is eating a lot of tuna, you should closely monitor any mercury poisoning symptoms. The most common symptoms of mercury poisoning caused by dogs eating tuna are;

If mercury poisoning is not treated, it can be deadly. However, this is not the only reason not to feed your dog tuna fish. Vets warn us that feeding dog tuna, especially fresh or raw, can lead to parasite infections. The food your dog consumes should be thoroughly cooked to avoid such issues.

The third reason to avoid feeding tuna to your dog is an enzyme called thiaminase. This enzyme will break down vitamin B1 in your dog’s body. All raw fish have this enzyme in them, so you should generally avoid feeding raw fish to your dog.

If you are considering including fish in your dog’s diet, check out this article - Fish for dogs: yes or no?

Can dogs eat raw tuna?

By now, this part should be pretty clear. Dogs should not eat raw tuna. It can lead to different health issues, and there is a chance your dog can get mercury poisoning. Raw tuna can be filled with parasites, and it should be widely avoided. In fact, you should never feed your dog any type of raw fish. Make sure the fish you include in your dog’s diet is treated correctly.

fresh tuna catch

Can dogs eat canned tuna?

Theoretically, some types of canned tuna could be fed to dogs. However, we are generally against feeding tuna to your dog. The long-term risks are, in our opinion, greater than the short-term benefits. The issue with that is that dogs should eat a lot of tuna to feel its benefits, but too much tuna increases the chance of getting one of these issues.

Tuna in oil, seasoned tuna, or any other tuna not canned in water should be avoided. Dogs cannot digest these things, and feeding them those types of canned tuna can be dangerous.


There are far healthier fish alternatives than tuna for dogs. Some of the best dog foods out there include fish like mackerel, salmon, herring, or flounder, a far safer and healthier choice than tuna. These fish offer a lot fewer risk factors than tuna. If you are adamant about feeding tuna to your dog, you should give them only small amounts and not more than two times a week. Treat it as you would treat dog treats.

A bit every now and then probably won’t hurt your dog, but overfeeding your dog on tuna will cause more health issues than it will solve.

The best thing you can do is consult your vet about your dog’s diet. Make sure you tell them your concerns and suggestions. They can tell you everything you need to know about your dog’s diet, and in the meantime, you can check this list of suggestions we have on the best dog foods currently on the market - Best dry dog food.

World Dog Finder team

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