Can Dogs Eat Tuna Fish?

Your pet dog is one of your most treasured family members. You want the best health, home, food, and fun for them. Knowing what your canine companion can and cannot eat is essential to having a healthy, happy pup. So the big question here is, can dogs eat tuna?

Dr. Jess will answer this question and more below:

If you're short on time, the quick answer is that dogs can have some forms of tuna fish – but you must make sure to feed them correctly-prepared tuna and in safe moderation. Please read on further to learn about specifics, before you decide to offer your dog any form of tuna.

This article will discuss proper canine diets, why tuna can be served, and just how to do it safely.

Dog food companies commonly use tuna as one of their many ingredients.

However, dog food experts have started arguments regarding the safety of feeding fish to dogs.

Topics such as an increase in the risk of mercury poisoning, hypernatremia, as well as thiamine inactivation are a few of the concerns of many experts.

Well, is tuna fish really a health threat to the canine species or are we overthinking this? Let me explain my thoughts…

It’s always best practice to double-check which foods your dog can and can not eat because many foods that are completely safe and healthy for humans are actually very risky for dogs to eat, or even poisonous or deadly to them.

That's why I am so glad that you are here making an informed decision before feeding your dog this fish feast!

What Do Dogs Eat?

Some dogs aren’t too picky about what they eat. They’ll eat whatever you try to give them.

Some dogs are pickier than others. Pickier puppies can be hard to properly feed.

A common pet canine diet consists of a complete dry or wet feed and possibly supplements in some specific cases (not all pet dogs need supplements).

There is also foraging if the dogs are allowed to roam or are feral, and of course there are treats!

The diet of every dog breed can very and is important to know when offering food to your dog.

An improper diet could put your dog at risk of having problems properly digesting their food and absorbing nutrients correctly. And we don’t want that now do we???

So let’s talk specifically about tuna and how it could affect your dog’s diet and overall health.

What is Tuna?

Tuna are a migratory saltwater fish that are part of the mackerel family.

They have a very sleek, streamlined body that allows them to propel themselves quickly through the water, turning them into one of the fastest fish known. Tuna can clock in at over 40 miles per hour!

Tina is found in warm ocean waters and is commercially fished for human consumption.

There are many different types of tuna, with different colors, shapes, and sizes.

Tuna can range from 1 foot to 15 feet in length and can grow to weigh over 1500 pounds!

It is thought that the oldest of tuna can reach a ripe old age of 50 years old, although a few types of tuna are close to extinction.

Different Types of Tuna:

There are over 20 types of tuna found in nature, but only 5 or so are edible and safe for consumption. These tuna types include:

• yellowfin
• skipjack
• albacore
• bigeye
• bluefin

Tuna Nutrition Basics:

Tuna in general has many health benefits that are in large part due to the number and amount of vitamins, minerals, and nutrients found in the fish meat. 

• Antioxidants: Tuna contains antioxidants, a factor that may help reduce the actions of free radicals in the body.
• High in Protein: Yuna meat is high in quality protein as well as other nutritional factors!
• Saturated Fat Levels: Tuna fish is lower in saturated fats, which may help individuals with high blood pressure and general overall cardiovascular health.
• Easy on the Sodium: Tuna is fairly low in sodium compared to other options.
• Contains Vitamins: There is a considerable amount of vitamin D, vitamin B12, niacin, vitamin B6, and riboflavin.
• Fatty Acids: Tuna fish contains omega-3 fatty acids, which help to reduce omega-6 fatty acids and cholesterol in blood vessels.
• Level of Minerals: Tuna is rich in potassium, magnesium, iron, iodine, choline, phosphorus, choline, and selenium (AKA, “Selenoneine” – which may be able to bind to mercury and protect cells from mercury damage and poisoning!).

Theroetically, tuna could be potentially good for dogs because of its high vitamin and mineral content and the presence of omega-3 fatty acids and antioxidants.

Do Dogs Like Tuna?

Dogs are naturally carnivores. Most dogs like the taste of meat.

The flavor of fish, including tuna, is usually a delicious one for most dogs.

So yes, most dogs like the taste of tuna fish.

Can Tuna Be Harmful to Dogs?

There is an ongoing debate about whether or not it is safe and okay for dogs to eat tuna.

Some vets and pet nutritionists say that dogs can eat tuna and be healthy and happy – no worries. Other pet experts say the opposite – they are against feeding tuna to dogs. 

Then there are even others who suggest feeding only small amounts of tuna to dogs is okay every once in a while.

Before we can decide whther tuna is safe to feed our dogs, we need to first understand some of the risks involved if we do feed our dogs tuna.

There are 3 major reasons why many experts say that you should not feed your dog tuna fish. These three big factors include:

Harmful Reason #1: High Mercury Levels

The #1 reason pet health experts have this tuna debate is the research showing or suggesting high levels of mercury contained in the fish.

Fresh tuna has much higher levels of mercury than other types of fish, such as flounder, salmon, or tilapia. Skipjack and albacore tuna are the two tuna types that contain the lowest amounts of mercury in the tuna family.

Why does tuna contain so much mercury compared to other types of fish caught and sold for consumption?

Industrial pollutants, such as coal plants for instance, leak mercury, and that mercury then flows into lakes, rivers, and oceans.

Once in the water, it can be comsummed by the aqualife, and therefore can be seen accumulating in fish too.

The larger the fish and the older it lives to be, the higher the concentration of mercury in its tissues.

Tuna can live longer and have the potential to grow bigger in comparison to other edible fish, allowing for an increase in mercury levels to accumulate inside the fish's meat.

If you feed your dog fish that contains mercury, there will be the potential for mercury poisoning, especially if fed large amounts for a long period of time.

Mercury poisoning can kill your dog if physical signs are not noticed and the pup is not treated quickly.

Symptoms of Mercury Poisoning in Dogs

• Anxiety or nervousness
• Loss of coordination
• Diarrhea (watery or bloody)
• Emesis (vomiting) blood
• Tremors
• Kidney damage (inability to urinate, abdominal swelling, shaking, whimpering)
• Loss of feeling in paws
• Hair loss
• Blindness

If you notice these symptoms in your canine companion, contact your local veterinarian immediately.

Harmful Reason #2: Parasites and Contamination

Just like when preparing fish to serve your human family, you should always properly cook the fish thoroughly before feeding it to your dog in order to avoid any issues with the consumption of parasites.

Parasites commonly found in fish meat are normally killed by heat during the cooking process.

Harmful Reason #3: Thaminase and Vitamin B1 (and even salt!)

One big reason for many to be concerned about feeding dogs tuna is the enzyme thiaminase.

Raw tuna, or any raw fish for that matter, contains an enzyme called ‘Thiaminase‘.

This enzyme is responsible for breaking down any thiamine (vitamin B1) your dog ingests, but if you properly cook the fish before eating it, the heat from cooking will make this enzyme useless in this regard.

Tuna features another health threat for dogs due to it's high concentration of another factor – sodium.

Tuna live in salty waters and their meat can absorb the salt (sodium chloride), meaning that much of the tuna available to us to eat may be high in sodium.

Having a buildup of sodium in your dog can lead to them having hypernatremia (too high sodium concentrations), which can lead to serious illness.

That being said – one can of tuna will not lead to this diagnosis!

Your dog would need large amounts over quite a long period of time to this this condition come to fruition.

Dog Food Allergy to Tuna Fish:

A dog can develop an intolerance or an allergy to any food, so there is always the possibility that your dog is allergic to fish or tuna.

If you suspect your dog is allergic to tuna do NOT feed tuna to your dog.

If your dog is allergic to tuna and accidentally ingests it, go to your nearest animal emergency room immediately.

Common symptoms of adverse/allergic reaction to food:

• Swelling of body parts (ex. facial swelling)
• Nausea/vomiting
• Diarrhea
• Itching/Increased grooming
• Fever
• Lethargy
• etc.

Can Dogs Eat Tuna?

Tuna, given in small amounts periodically, is most likey just as healthy for your dog as it is for you.

Therefore, yes, dogs can eat tuna. 

Moderation is key; never go overboard when feeding tuna for dogs. Small amounts every once in a while is okay for most dogs.

Dogs can have tuna fish but only one or two times per week in small, controlled amounts.

Consider the type of tuna that you're feeding your dog – smaller species like skipjack and albacore should be top choice over larger tuna types like yellowfin or bluefin tuna.

Can Dogs Eat Canned Tuna?

Canned tuna can be a healthy, protein-packed snack for your dog.

Canned tuna must be served in appropriate small, manageable amounts, and preferably skipjack or albacore rather than the larger tuna fish because of mercury and sodium concerns mentioned above.

If feeding your pup canned tuna, make sure to look for tuna in water rather than oil, and if offering your dog the canned tuna's water, be sure that the tuna does not have any added salt.

Look for the phrase “no salt added” on the can's packaging.

Is Tuna Beneficial For Dogs?

Tuna has several health benefits for dogs, just as it does for humans, discussed earlier in this article. Some of the benefits for your dog include:

Is Tuna Good For Dogs?

Tuna, like all kinds of fish for dogs, is a great meat and protein source.

Not only does tuna contains high levels of protein, but it contains high levels of healthy fats, minerals and vitamins too.

Tuna is high in Omega-3 fatty acids which can help make your dog's skin and coat silky, shiny, and smooth.

Tuna is also extremely beneficial for overall development and function of many of the body's systems due to the great source of many vitamins and minerals found within it.

Can Dogs Eat Raw Tuna? 

Can dogs have tuna that hasn’t been cooked or isn't canned?

Hard no. Not only should dogs not eat raw tuna but your canine friend should not eat any type of raw fish or seafood.

Raw tuna fish is definitely not the safest choice.

Raw fish can carry bacteria and parasites that may be damaging to the body once consumed.

Also remember that raw fish contains the enzyme thiaminase, and enzyme that can inactivate thiamin (vitamin B1) in your dog's body.

Cooking fish takes care of this issue, destroying the thiaminase.

Your pup will likely love his tuna treat no matter what form it comes in so better to be safe and only serve them cooked tuna if any at all!

How to Serve Tuna to Dogs:

As convenient as it might be to just let your dog have tuna fish, that's not the safest option for your pup.

Keep the following in mind when serving tune to your dog:

• When buying dog food like canned tuna, remember to buy the water-based cans of tuna (not tuna in oil!) without additional flavorings or seasonings.
• Try to find a tuna that has lower potential for increased mercury levels, either skipjack or albacore tuna, to avoid any chance of mercury poisoning.
• Make sure to properly cook the tuna to eliminate any parasites and harmful bacteria that may be present.
• You can try to steep the tuna in water overnight to get rid of as much salt as possible before cooking and serving it to your dog.
• Using fresh tuna? Feed cooked tuna to your dog with it first deboned. Dogs aren't great with bones and the bones can end up lodged in their air passage and present as a choking hazard for them.
• Do not add salt or seasonings to the tuna. Your dog will love the tuna just fine without any additives that could cause them more harm than good.
• Introduce tuna little by little. It’s definitely a good idea to take it slowly. Give your pup a little at a time and wait to see how they react to the treat before proceeding with giving them another bite or two.

Fish types considered by many to be safer for dogs, are the fish most commonly used in commercial dog food – salmon, whitefish, herring, flounder, and Arctic char.

Other types of fish like salmon, for instance, feature the same nutritional benefits but with a decreased risk of mercury poisoning.

And remember that dogs need more than a bowl or plate of fish – they need a complete and balanced diet.

Whichever food you choose for your dog, whether it is fish or another protein source, fresh meat or store-bought kibble, it needs to have the AAFCO label indicating the diet is complete and balanced for your dog’s life stage.

AAFCO approved foods have gone through testing and compliance to make sure that the diet is safe and healthy for your pet.

Dogs already get everything that they need from their kibble or canned food.

How Much Tuna Can My Dog Have?

Can dogs eat tuna? As I mentioned previously, it depends…  

Small amounts of cooked or canned tuna don’t contain enough mercury to cause a problem in your dog if given periodically.

Adult dogs should not eat cooked or canned tuna more than once or twice a week, in small amounts.

There is a big difference between feeding your dog tuna occasionally as a treat and making it a staple part of their diet. Treat tuna as a every-one-in-a-while special treat.

It's always better to be safe than sorry!

Can Puppies Eat Tuna?

I would never advise a puppy owner to feed this fish to their puppy. Nope.

Your pup's first months of life should consist of specialized puppy diets approved by your local veterinarian upon puppy exam.

Summary:

Dogs are carnivores that really love to hold true to that label!

They LOVE meat! Fish, a meat that is commonly consumed by humans is naturally enticing to our canine counterparts.

Allowing your pet to have a bite or two of cooked or canned (in water) tuna without seasonings, oil, flavorings, or bones, given every once in a while is okay.

Giving your pup a fishy treat every once in a while will not give them mercury poisoning or the other health issues that were discussed throughout this article.

If you are concerned about feeding your pet dog a tuna snack or you feel that the tuna that they have already snacked on didn't go well, contact your veterinarian for more guidance on what to do next.

Trust me, us vets are happy to help!

References Used in This Article:

• FDA, “Mercury Levels in Commercial Fish and Shellfish” U.S. Food and Drug Administration (FDA), 2017.
• Sheer, R., et al, “How Does Mercury Get Into Fish?” Scientific American, 2018.
• Mataljan, G., “Tuna: Nutritional Content,” World’s Healthiest Foods, 2018.
• Pendergrass, J., DVM, “Mercury in Dog and Cat Foods: Cause for Concern?” American Veterinarian, 2016.