Can Dogs Eat Canned Tuna?
What Pet Owners Need to Know

It’s lunchtime, and you’re making a tuna sandwich. Just as you open the can, your dog appears at your feet, wagging its tail and looking up at you with hopeful, desperate eyes. It’s a familiar moment for many pet owners, and it naturally raises the question: Can dogs even eat canned tuna?

The short answer is yes, but there are a few things to keep in mind about sharing this pantry staple with your pup. In this blog, we’ll cover the best type of canned tuna for dogs, how much is safe to feed your pet, the potential benefits, and a few risks to be aware of.

This article contains general information only. For advice specific to your dog’s diet, health, or portion sizes, please talk to your vet.

The RSPCA notes that plain, tinned fish like tuna, sardines or salmon in springwater is fine as an occasional treat for dogs, but shouldn’t become a regular part of their diet. When served simply in springwater, tuna can provide protein and omega-3 fatty acids for most healthy dogs.

That said, canned tuna won’t suit every dog equally. According to PetCo, dogs with existing health conditions, such as kidney disease or those on low-sodium diets, may be more sensitive to added salt, even in small amounts.

Puppies and smaller breeds can also react more strongly to new foods, including fish, while some dogs may have seafood allergies that can cause digestive upset or skin irritation. If your dog falls into any of these categories, it’s best to speak with your vet before introducing tuna. They can help you decide whether it’s suitable and how to introduce it safely.

Canned tuna is primarily for humans. But in limited quantities, it can also provide some nutritional benefits for your dog.

According to Petcloud, canned tuna has the following benefits for dogs:

• Lean protein, which helps support muscle health
• Omega-3 fatty acids, which may support skin and coat health
• Vitamins and minerals, including B vitamins that support overall health

While canned tuna can offer some nutritional benefits, most dogs should still get the majority of their nutrition from a complete and balanced dog food, which is why canned tuna is best thought of as an occasional extra rather than a daily staple.

The main concern with tuna, for both dogs and humans, is its mercury content. According to Food Standards Australia New Zealand (FSANZ), mercury builds up in fish as they grow, so the species used in your canned tuna matters. Sirena uses Yellowfin Tuna (Thunnus albacares), which is generally smaller and younger. This may mean lower mercury levels than in larger species, but it’s still important to limit how often you share it with your dog.

Other factors to be aware of include:

• Sodium (salt): Some canned tuna products contain added salt, which isn’t ideal for dogs. Too much sodium in your dog’s diet can lead to symptoms such as vomiting, diarrhoea, or lethargy.
• Oil-packed tuna: Tuna in oil is higher in fat and can upset your dog’s stomach or contribute to weight gain over time.
• Seasonings: Ingredients like onion and garlic, commonly found in flavoured tuna, can be harmful to dogs and should always be avoided.

There isn’t a one-size-fits-all portion when feeding canned tuna to dogs. Most vets suggest offering only very small amounts as an occasional treat. Frequency matters just as much as portion size.

As a general guide, serve:

• Teaspoon-sized amounts for small dogs
• Small spoonfuls for medium-sized dogs
• Slightly bigger portions for large dogs

Mix a small portion through your dog’s regular food to add variety, or offer it on its own as an occasional treat. Some pet owners also use small amounts as a reward during training or to encourage fussy eaters. Keep an eye on your dog for any signs of a reaction, such as diarrhoea, itchy skin, or vomiting. If you see anything concerning, stop giving canned tuna immediately.

If you decide to give your dog canned tuna, a few simple precautions can help:

• Choose the plain version in springwater.
• Check the label for no added salt, oil, or seasoning.
• Drain and rinse with water before serving.
• Offer canned tuna in small amounts only.
• Avoid feeding it daily.
• If you’re unsure, your vet can advise you further.

Following these tips helps ensure your dog can enjoy canned tuna without unnecessary risks.

Ultimately, a little canned tuna from time to time can go a long way for curious pups who like to share in mealtime moments. When it comes to your own meals, canned tuna is a convenient source of lean protein and omega-3s for everyday meals. Read our post ‘Can You Eat Canned Tuna Every Day?’ to learn more.

Explore Sirena’s range of canned tuna products available at your local supermarket.

Sources

RSPCA. (August 21, 2024). What should I feed my dog? Retrieved May 2026, from https://kb.rspca.org.au/knowledge-base/what-should-i-feed-my-dog/

PetCo. (March 18, 2026). Is Tuna Safe for Dogs? Retrieved May 2026, from https://www.petco.com/content/content-hub/home/articlePages/food-nutrition/can-dogs-eat-tuna.html?

Petcloud (December 24, 2024). Can Dogs Eat Tuna? Retrieved July 2026 from
https://www.petcloud.com.au/d/blog/can-dogs-eat-tuna/

Food Standards Australia New Zealand. (December 13, 2020). Mercury in fish. Retrieved May 2026, from https://www.foodstandards.gov.au/consumer/chemicals/mercury