Can Dogs Eat Tuna Safely?

Read this before giving your dog tuna 🐟

While making a tuna salad, have you ever thought about giving your dog a little taste?

While tuna isn’t outright toxic for dogs, there are still risks associated with it that you should know about.

The Dodo reached out to Dr. Claudine Sievert, a veterinarian working with Stayyy, and Sarah Lyman, a clinical pet nutritionist working with Sovereign Laboratories, to find the answer to the question: Can dogs eat tuna?

Is tuna safe for dogs?

Tuna can be enjoyed in small quantities by your pup (like if you have a tiny bit left in the can and don’t want to waste it), but it shouldn’t be considered a staple in your dog's diet due to its high mercury content.

While tuna does have some benefits (it’s a good source of omega-3 fatty acids, vitamin B12 and protein, and it’s low in overall fat), its nutritional benefits can be found in other kinds of fish, like salmon and sardines — and without the added risk.

“A better alternative to tuna is feeding sardines,” Lyman told The Dodo. “The little fish don't live as long as the big [tuna] and therefore don't hold onto toxins. They provide omega-3 fatty acids and are a rich source of iodine.”

​​Fresh tuna, in particular, has a higher mercury level than cooked or canned tuna and should not be given to your dog as a treat.

“If your dog snags a small amount of your food, you don't need to worry,” Dr. Sievert told The Dodo. “Tuna is not toxic to dogs, and a small amount will not cause mercury poisoning; however, you should try to keep cat food away from them since [some of] their food contains tuna.”

Can dogs eat tuna from a can?

Canned tuna is better for your dog than the fresh version, but you should still make sure you’re not giving your dog canned tuna that has any added seasoning or tons of salt as both of these aren’t good for your dog.

“If you're going to feed your dog tuna, you'll want to choose albacore tuna canned in water and give them a small serving,” Dr. Sievert said.

Potential risks of tuna

Tuna does carry along some risks when consumed in large quantities. A couple of them include:

Too much sodium

Tuna has a lot of sodium, which isn't good for dogs, especially when consumed in large quantities.

Signs that your dog has consumed too much salt include:

  • Vomiting
  • Diarrhea
  • Decreased appetite
  • Increased thirst
  • Excessive urination

Mercury poisoning

Tuna has more mercury in it than many other fish. If your pup eats too much tuna, it can lead to mercury poisoning.

Signs of mercury poisoning include:

  • Vomiting blood
  • Watery or bloody diarrhea
  • Abdominal swelling
  • Kidney damage
  • Hair loss
  • Blindness
  • Anxiety
  • Loss of coordination
  • Tremors

“A small amount of tuna won't cause harm, because it's not the tuna that's toxic; however, if your dog has eaten a large amount of tuna and starts showing any of the signs above, take him to the vet right away,” Dr. Sievert said.

A food allergy

Fish allergies can be common in pets, so it’s something to watch out for if you choose to feed your pup tuna.

“Feeding tuna could pose a risk if your dog has a sensitivity to it and develops an anaphylactic reaction, hives or gastrointestinal upset,” Lyman said.

So while sharing a little bite of tuna probably won’t hurt your pup, this isn’t a fish you should consider to be part of your dog’s overall diet.