Can dogs eat tuna?
Maybe — small amounts of cooked tuna are safe for dogs, but tuna contains relatively high levels of mercury compared to other fish. Occasional servings are fine, but tuna should not be a regular part of your dog's diet due to mercury accumulation concerns.
Seafood · 132 kcal per 100 g
Benefits and risks
Benefits
- High in protein and omega-3 fatty acids
- Rich in selenium, which helps offset mercury effects
- Good source of vitamin D and B vitamins
- Highly palatable — most dogs love the taste and smell
- Contains potassium and magnesium
Risks
- Higher mercury content than most other fish — can accumulate over time
- Canned tuna in oil adds unnecessary fat — choose tuna in water
- Tuna steaks may contain bones that can cause choking
- Excessive tuna consumption can cause mercury poisoning (tremors, vision loss)
- Seasoned or sushi-grade raw tuna is not recommended
Recommended serving size
Adjust portions based on your dog's weight, age, and activity level. Treats and snacks should make up no more than 10% of daily calories.
| Dog size | Weight range | Serving |
|---|---|---|
| Small dog | Under 20 lbs (9 kg) | 1 tablespoon, cooked or canned in water |
| Medium dog | 20–50 lbs (9–23 kg) | 2 tablespoons, cooked or canned in water |
| Large dog | Over 50 lbs (23 kg) | 3 tablespoons, cooked or canned in water |
How to prepare and serve
Preparation
Cooked tuna (baked or steamed, plain) or plain canned tuna in water are both acceptable. Drain canned tuna thoroughly. Choose chunk light tuna over albacore — it has significantly less mercury. Remove any bones from fresh tuna. Never add mayo, seasoning, or serve as tuna salad. Avoid raw tuna. Keep portions small and infrequent due to mercury concerns.
Frequency
Once a week at most — less is better due to mercury.
Key nutrients
- Protein
- Omega-3
- Selenium
- Vitamin D
- Vitamin B12
- Potassium
Frequently Asked Questions
- Tuna is a large, long-lived predatory fish that accumulates mercury through the food chain — a process called bioaccumulation. The mercury in tuna is primarily methylmercury, the most toxic organic form, which builds up in the body over time faster than it can be eliminated. Dogs who eat tuna regularly can develop mercury poisoning, with symptoms including tremors, loss of coordination, vision problems, and kidney damage. Smaller dogs are at higher risk because it takes less mercury to reach toxic levels. Chunk light tuna (skipjack) has about one-third the mercury of albacore (white) tuna.
- For dogs, canned chunk light tuna in water is generally the better choice over fresh tuna steaks. Chunk light tuna comes from skipjack, a smaller species with significantly lower mercury levels than the larger albacore, yellowfin, or bluefin tuna used for steaks. Canned tuna is also pre-cooked, eliminating parasite risk, and easier to portion in small amounts. If using canned, always choose tuna packed in water (not oil) with no added salt, and drain thoroughly. Fresh tuna is fine occasionally if cooked thoroughly, but the mercury content is typically higher.
- Several fish offer similar omega-3 benefits with much lower mercury levels. Salmon is the top recommendation — rich in EPA and DHA with moderate mercury. Sardines are excellent — small, short-lived fish with very low mercury and high omega-3 content. Anchovies are similarly safe and nutrient-dense. Whitefish like cod, haddock, and pollock are low in mercury and fat. Herring is another good omega-3 source with minimal mercury concerns. As a general rule, smaller, shorter-lived fish accumulate less mercury than large predators like tuna, swordfish, and shark.
Related seafood
Crab
CautionCooked crab meat is safe in small amounts, but the shell is dangerous and imitation crab is not recommended.
Lobster
CautionPlain cooked lobster meat is safe in small amounts, but the shell is dangerous and most preparations include unsafe ingredients.
Salmon
SafeExcellent source of omega-3 fatty acids for skin, coat, and joint health — must be fully cooked. Never feed raw Pacific salmon.
Sardines
SafeSmall, nutrient-dense fish with very low mercury — one of the best omega-3 sources for dogs.
Browse all dog-safe foods
DogDataHub covers 100+ foods with clear safety verdicts, serving sizes, and prep tips.
See all foods