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Can Dogs and Cats Eat Tuna?

About Tuna

A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae (mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna up to the Atlantic bluefin tuna, which averages 2 m (6.6 ft) and is believed to live up to 50 years. Read more on Wikipedia →

Tuna for Dogs

Contains omega-3 fatty acids. Limit intake due to mercury content. Fresh cooked tuna is better than canned.

The general rule of thumb is the 10% guideline — treats and extras should not exceed 10% of your dog's total daily calories. The remainder should come from a balanced commercial or vet-formulated diet. Introduce tuna gradually, watching for any sign of digestive upset over the first 24–48 hours.

Nutrition per 100 g

Tuna, ahi or yellowfin, frozen, wild caught — 102.0 kcal, 24.7 g protein, 0.39 g fat, -0.1 g carbohydrates. Source: USDA FoodData Central.

Portion guide by body weight

• Toy / small (under 5 kg / 11 lb): a teaspoon-sized piece, 2–3 times per week
• Medium (5–15 kg / 11–33 lb): a tablespoon-sized portion, up to daily
• Large (15–30 kg / 33–66 lb): two tablespoons, up to daily
• Giant (30 kg+): a small handful, up to daily

Tuna for Cats

Cats love tuna but it can cause mercury accumulation and thiaminase can destroy vitamin B1. Too much canned tuna can lead to malnutrition. Use only as an occasional treat, never as a primary food.

Because cats process many compounds differently from dogs, the safety threshold for tuna can be much lower. Even a 'small taste' that a dog would handle may bother a cat. If you have any doubt, simply don't offer it.

How to Serve Tuna Safely

1. Wash thoroughly with cold water to remove dirt, pesticide residue, or surface bacteria.
2. Remove any inedible parts — pits, seeds, stems, leaves, or rinds — unless those are clearly safe for the species.
3. Cut into bite-sized pieces. Small dogs and cats can choke on anything larger than their windpipe.
4. Serve plain. No salt, sugar, butter, oil, garlic, onion, or seasoning of any kind.
5. Refrigerate leftovers in a sealed container and use within 24 hours.

If you're freezing portions of tuna as a hot-weather treat, freeze in single-serving sizes so you're not thawing more than your pet will eat in one session.

What to Avoid

• Sugar, syrup, or artificial sweeteners. Xylitol in particular is severely toxic to dogs and is hidden in sugar-free gum, peanut butter, baked goods, and even some toothpaste.
• Garlic and onion in any form. Both are toxic to dogs and cats, including powdered forms in sauces and seasoning mixes.
• Chocolate, coffee, or alcohol served alongside or mixed in.
• Salt and salty cured products. Pets can develop sodium ion poisoning from amounts that seem trivial to a human.
• Cooked bones if Tuna is served with meat. Cooked bones splinter and can perforate the gut.

Signs of a Problem

Even with safe foods, individual sensitivities are real. Stop feeding and call your vet if you see any of:

• Vomiting or diarrhea, especially repeated episodes within a few hours
• Excessive drooling, lip-licking, or pacing
• Lethargy, weakness, or unwillingness to move
• Difficulty breathing, swelling around the face, or hives
• Tremors, twitching, or seizures — always an emergency

If your pet's symptoms are severe, contact an emergency veterinarian immediately. In the United States the ASPCA Animal Poison Control Center is reachable 24/7 at +1 (888) 426-4435.

Frequently Asked Questions

Can dogs eat tuna?

Yes, in moderation. Tuna is a safe occasional treat for most healthy dogs when prepared correctly. Stick to the 10% treat rule and avoid added sugar, salt, or spices.

How much tuna can my dog eat a day?

A teaspoon to a tablespoon for small dogs, a tablespoon to two for medium dogs, and up to a small handful for large dogs. Treats and extras should not exceed 10% of daily calories.

Can puppies eat tuna?

Puppies over 8 weeks old can usually try a tiny piece of tuna. Their digestive systems are sensitive, so introduce gradually and watch for vomiting or loose stools.

Is tuna safe for cats too?

In small amounts, yes — see the cat section above. Cats are obligate carnivores and don't need fruit or vegetables nutritionally.

Can dogs eat cooked tuna?

Yes, plain cooked tuna is usually fine. Avoid adding butter, oil, salt, sugar, garlic, or onion — all of which can upset or harm pets.

What should I do if my dog ate too much tuna?

Watch for vomiting, diarrhea, or lethargy over the next 12–24 hours. If symptoms appear or you're concerned, call your veterinarian. The ASPCA Poison Control line (+1 888 426 4435) can also advise.