Can Dogs Eat Tuna? Risks, Safe Servings & Best Types

You’ve seen that pleading look when you pop open a can of tuna. It’s easy to want to share. But before you do, there’s a careful balance between a healthy treat and a hidden risk. Here’s what dog owners need to know about tuna – how much is safe, which kind to choose, and when to skip it entirely.

Mercury concentration in tuna (average, ppm): 0.128 ppm (skipjack) to 0.689 ppm (albacore) per FDA ·
Safe tuna serving size for a 30-lb dog: 1 tablespoon (canned in water) once per week ·
Maximum mercury intake limit (EPA reference dose for humans): 0.1 micrograms per kg body weight per day

Six key data points that separate a safe tuna treat from a risky one:

Is canned tuna ok for dogs?

The short answer: yes, but only if you take precautions. Canned tuna in water is the safest option because it avoids extra fat and sodium. The bigger concern is mercury – tuna is a predatory fish that accumulates methylmercury, and dogs are not immune. According to the American Kennel Club (leading U.S. canine registry), neither canned nor raw tuna is considered safe for regular consumption. However, Purina (major pet food manufacturer) takes a softer stance, stating that when fed very occasionally in small amounts, tuna is unlikely to cause problems.

Benefits vs risks of canned tuna for dogs

• Benefits: Tuna provides protein and omega‑3 fatty acids (about 0.5 g EPA/DHA per 100g). These can support a dog’s skin, coat, and joints when given sparingly.
• Risks: Mercury accumulation is the primary risk. The EPA reference dose for humans is 0.1 mcg per kg body weight per day – a threshold that small dogs can exceed with even a few tablespoons of albacore tuna per week. Additionally, tuna canned in brine adds sodium that can strain the kidneys (Pooch and Mutt).

Why mercury in tuna matters for dogs

Mercury is a neurotoxin that builds up in the body over time. Dogs that eat tuna frequently may develop tremors, poor coordination, and kidney damage – symptoms of mercury poisoning that match those seen in people (Impact Dog Crates). Small dogs are at higher risk because their lower body weight means the same dose of mercury has a stronger effect. Veterinary toxicologists note that the exact safe canine threshold is unknown, so conservative feeding is the only prudent approach.

How much tuna can a dog eat?

Size matters. A 30‑pound dog can safely eat about one tablespoon of canned light tuna once per week. For a smaller dog — say under 20 pounds — even that amount may push mercury intake beyond safe analogs. Fully Healthy suggests small dogs get no more than a teaspoon or two of light tuna per week, with veterinary approval first. The We Feed Raw (pet nutrition blog) advises that light tuna should not be fed more than once or twice a week.

Safe serving sizes based on dog weight

The table below translates body weight into a maximum weekly serving using EPA-derived thresholds:

How often can a dog eat tuna?

• Once per week maximum for most dogs.
• Never feed every day — mercury accumulates, and daily consumption can exceed safe levels within a month (Pawlicy).
• If you feed tuna, skip other high‑mercury fish like albacore or bigeye that week.

The catch: Treat frequency is the single most ignored factor. Owners who feed “just a little” every day are the ones who risk chronic mercury exposure. A weekly tablespoon is a treat; anything more becomes a source of accumulated toxin.

Which canned tuna is good for dogs?

Not all tuna is equal. The type you choose — and the liquid it’s packed in — determines both safety and toxicity risk. Canned tuna in water (no salt added) is the best choice for dogs, according to Pawlicy. Tuna in oil adds unnecessary fat that can trigger pancreatitis, while tuna in brine delivers a sodium load that can stress the kidneys (Pooch and Mutt).

Tuna packed in water vs oil vs brine

• Water (no salt added): Best choice for dogs. Low sodium, low fat, drains easily.
• Oil (vegetable or olive): High in fat — risk of pancreatitis. Rinse if unavoidable, but avoid routinely.
• Brine: Very high sodium (500–600 mg per 100g). Can cause salt poisoning or worsen kidney disease.

Should you buy chunk light or albacore tuna for dogs?

Chunk light tuna, typically skipjack, has the lowest mercury content (0.128 ppm per FDA). Albacore (white) tuna averages 0.689 ppm — more than five times higher. Bigeye tuna, sometimes sold as “ahi,” is even riskier and should not be fed to dogs (We Feed Raw). The rule: chunk light is the only type that should go into your dog’s bowl, and even then only sparingly.

Why this matters: A 30‑lb dog that eats one tablespoon of albacore per week would receive roughly 2.5 times the mercury equivalent of the human reference dose. Using chunk light cuts that to a safer fraction.

What’s confirmed vs. what remains unclear

Weighing the evidence: some facts are solid, others are extrapolations.

“Neither canned nor raw tuna is considered safe for dogs to consume regularly due to mercury content.”

— American Kennel Club

“When fed very occasionally in moderation, dogs can eat tuna as it’s unlikely to cause health issues.”

— Purina

The two most authoritative voices on canine nutrition disagree. AKC takes a zero-risk stance; Purina allows limited feeding. The safest path for dog owners is to treat tuna like a condiment — a tiny, infrequent taste — not a regular part of the diet.

For pet owners concerned about mercury accumulation, a companion guide offers more details on mercury levels in tuna and safe serving limits for different dog weights.

Frequently asked questions

Related reading

• Can Dogs Eat Cherries? – Another guide on safe human foods for dogs.
• Is Collagen Good for You? Benefits, Risks & Science – Explore the science behind another popular dietary component.

For dog owners, the decision is clear: feed tuna only as an occasional treat, measured by weight, chosen as chunk light in water, and drained of all liquid. Any more than that, and the mercury risk becomes a real concern — especially for small breeds that can’t afford the accumulation.