Fish & seafood · updated 2026-09-12
Can cats eat tuna?
Cats adore it, but keep it occasional.
Why
Tuna is not a complete food for cats: it lacks vitamin E and balance, carries mercury, and cats can become 'tuna addicts' who refuse proper food. Tinned in water only.
How to serve it
A teaspoon as a treat or to tempt a poorly cat, not daily.
If they eat too much
Mercury toxicity with regular feeding; steatitis (yellow fat disease) from excessive fish diets.
How much tuna for my cat?
A daily maximum for a healthy adult cat, kept inside the 10% treat rule. Enter body weight.
Up to 3 g a day — a pea-sized piece · tinned in water.
Treats of all kinds should stay under about 10% of daily calories. Puppies, kittens, seniors and pets with a medical condition: ask your vet first.
And for dogs?
In moderation. Small amounts of tinned tuna in water, occasionally. Can dogs eat tuna? →
Related foods for cats
- Raw fishAvoid
- SalmonSafe
- Shrimp & prawnsIn moderation
- ApplesIn moderation
- BananasIn moderation
- BreadIn moderation
See the whole list: Can cats eat…? · printable fridge chart
This guide is general information for healthy adult cats, based on published veterinary guidance (ASPCA, Pet Poison Helpline, AKC, VCA). It is not a substitute for advice from your own vet, who knows your cat's weight, age and medical history. If you are unsure, ask them before sharing any human food.