Can cats eat Tuna?
Caution. Small amounts of tuna as an occasional treat are fine, but tuna should not be a staple food — it's deficient in nutrients cats need and high in mercury.
If your cat has eaten tuna
- No emergency for a one-off tuna exposure.
- If your cat regularly eats tuna as a major food source, speak to your vet about switching to a nutritionally complete diet.
What's the full picture?
Cats love tuna, and that's part of the problem — a tuna habit can lead them to refuse balanced food. Canned tuna is also low in vitamin E and taurine compared to proper cat food, and repeated feeding can cause a condition called yellow fat disease (steatitis) from chronic vitamin E deficiency.
Tuna — particularly larger species like bluefin and yellowfin — accumulates mercury, and cats are small enough that cumulative mercury exposure is a genuine concern.
Tuna in brine or oil adds salt and fat to the mix. If you give tuna occasionally, pick tuna in spring water, drain it well, and treat it as a rare treat, not a daily item.
Safer alternatives
- Plain cooked white fish (cod, haddock) in small amounts
- Commercial fish-flavoured cat food
Questions owners ask
How often can I give my cat tuna?
As an occasional treat — no more than once a week, and only a small amount. It should never replace proper cat food.
Is the tuna in cat food safe?
Cat-food tuna is formulated as a complete diet with added vitamins and taurine. That's different from canned human tuna, which is not nutritionally complete for cats.
Related
About this guidance
Every entry on this site is compiled from published UK veterinary toxicology sources — International Cat Care, Veterinary Poisons Information Service (VPIS) references, RCVS-registered practice materials, and peer-reviewed feline medicine literature. Where the evidence is mixed, we err on the cautious side because cats are unusually sensitive to many common substances that are harmless to humans and even to dogs.
This is general information written for UK cat owners. It is not personalised veterinary advice for your specific cat, their age, weight, medical history, or the exact exposure you're dealing with. If your cat has eaten something or is unwell, call your vet first. The Animal PoisonLine on 01202 509000 is available 24/7 for a small fee and can tell you whether an emergency visit is needed.
Entries are reviewed and updated as new research emerges. Spotted an error? Let us know — corrections are investigated and applied within 24 hours. For more context on how we work, see about and our full disclaimer.
Last reviewed: · By the What Can My Cat Eat? editorial team