Can Dogs Eat Tuna?

Can Dogs Eat Tuna?

While tuna is a protein source, it's not an ideal food for dogs. Tuna can contain high levels of mercury, which can be harmful over time. Additionally, tuna packed in oil or brine adds unnecessary fat and sodium to your dog's diet, so choose canned versions in water. Small amounts of plain, cooked tuna on rare occasions might be okay, but overall it's best to choose healthier and safer protein options specifically formulated for dogs.

Dogs can eat tuna, but it should be offered in moderation due to concerns about mercury content and the nutritional balance of a dog’s diet. Tuna can be a good source of protein and omega-3 fatty acids, which can benefit your dog’s skin, coat, and overall health. However, the way tuna is prepared and served to dogs is crucial to avoid any health risks.

Nutritional Value

Tuna in correct amounts provides several nutritional benefits for dogs, including:

  • Protein: High-quality protein supports muscle development and repair.
  • Omega-3 Fatty Acids: Promote healthy skin and a shiny coat, and can support heart health.
  • Vitamins B3, B6, and B12: Essential for energy production and maintaining healthy cells.
  • Minerals: Selenium, magnesium, and potassium, which support various bodily functions, including the immune system and muscle health.



Value per 100g of Tuna

Small Dogs (1-10 kg) Daily Requirement*

Medium Dogs (11-26 kg) Daily Requirement*

Large Dogs (27+ kg) Daily Requirement*


~130 kcal

200 - 400 kcal

400 - 800 kcal

800 - 1,600 kcal


~28 g

25 - 50 g

50 - 75 g

75 - 100 g


~1 g

10 - 20 g

20 - 40 g

40 - 80 g

Omega-3 Fatty Acids

~0.2-0.5 g

0.1 - 1.5 g

1.5 - 2.5 g

2.5 - 3.5 g

Vitamin B3 (Niacin)

~8.3 mg

4 - 11 mg

11 - 15 mg

15 - 20 mg

Vitamin B6

~0.5 mg

0.18 - 0.55 mg

0.55 - 1.1 mg

1.1 - 2.2 mg

Vitamin B12

~2.5 µg

9 - 13 µg

13 - 20 µg

20 - 50 µg


~92 µg

36 - 90 µg

90 - 120 µg

120 - 200 µg

*These daily requirements are rough estimates and will vary depending on the individual dog's health, lifestyle, and dietary needs. Always consult with a veterinarian for personalized dietary advice.

Despite these benefits, tuna’s mercury content is a concern, as high levels can lead to mercury poisoning in dogs over time.

Food Suitability

Tuna is suitable for dogs in small amounts. It's best served as an occasional treat rather than a regular part of their diet. Fresh or canned tuna in water (not oil) without any added salt or spices is the safest choice.

Feeding Instructions

When introducing tuna to your dog's diet, consider the following guidelines:

  • Moderation: Keep tuna as an occasional treat. For small dogs, a teaspoon is enough. Medium to large dogs can have a tablespoon.
  • Preparation: Ensure the tuna is cooked (if fresh) and does not contain any added ingredients harmful to dogs.
  • Canned Tuna: Choose tuna canned in water rather than oil and ensure it has no added salt or spices.


Feeding tuna to dogs comes with potential risks:

  • Mercury Poisoning: Regular consumption of tuna can lead to mercury accumulation, which is toxic.
  • Sodium Content: Canned tuna can contain high levels of sodium, which is not suitable for dogs.
  • Allergies: Some dogs may be allergic to fish, including tuna. Monitor your dog for any signs of an allergic reaction.

Allergies and Sensitivities

Watch for signs of an allergic reaction, including itching, swelling, gastrointestinal upset, or difficulty breathing. If you observe any of these symptoms, discontinue feeding tuna and consult your veterinarian.

Although, a food allergy is rare, more common is a food intolerance. It is estimated that up to 10% of dogs suffer from some food intolerance. 

At My Pet Sensitivity we offer a dog food intolerance test that can help give you peace of mind before feeding your dog new foods.

Alternatives to Tuna

If you're seeking alternatives to tuna for your dog, consider other fish or lean proteins that are lower in mercury and safe for canine consumption:

  • Salmon: A great source of omega-3 fatty acids, but should always be cooked to avoid the risk of parasites.
  • Sardines: Low in mercury and high in omega-3 fatty acids; opt for those canned in water without added salt.
  • Chicken: A lean protein that's generally safe for dogs when cooked and served without bones or seasoning.


Can tuna cause mercury poisoning in dogs?

Yes, similar to humans, dogs can suffer from mercury poisoning if they consume too much tuna over time. It's crucial to limit tuna intake and consider safer alternatives.

How often can I feed my dog tuna?

Tuna should be an occasional treat rather than a regular part of your dog’s diet. Once every few weeks is a general guideline, but less frequently is advisable for smaller dogs due to the higher risk of mercury accumulation.

What are the signs of mercury poisoning in dogs?

Symptoms can include vomiting, diarrhea, loss of coordination, and hair loss. If you suspect mercury poisoning, contact your veterinarian immediately.

Portion Sizes (Table Format)

When feeding tuna to your dog, follow these suggested portion sizes to keep it as a safe and enjoyable treat:

Dog Size

Suggested Portion


1 teaspoon of cooked tuna


1 tablespoon of cooked tuna


1-2 tablespoons of cooked tuna

These portions are intended as occasional treats, not regular meal replacements. Always ensure the tuna is plain, cooked, and free from any bones or seasoning.


Tuna can be a nutritious treat for dogs, offering benefits like protein and omega-3 fatty acids. However, due to the risks associated with mercury content, it's important to offer tuna in moderation, following the recommended portion sizes based on your dog's size. Always opt for plain, cooked tuna without added ingredients, and consider lower-mercury fish alternatives to diversify your dog's diet safely. Before making significant changes to your dog's diet or if you have concerns about food safety, consulting with a veterinarian is always the best course of action. This ensures your furry friend enjoys their treats without compromising their health.