Can cats eat tuna?
Not regularly. A small amount of tuna may not cause harm, but tinned tuna for people lacks nutrients cats need, can be high in salt and mercury, and some vets advise against it even as a treat. It is never a complete diet.
Updated:
Why
Sources disagree, so we use the stricter level. RSPCA Australia allows tinned tuna in spring water as an occasional treat. VCA says cats shouldn't eat tuna, not even as a treat, because it lacks essential nutrients and has too much unsaturated fat. Cats Protection warns it can be high in salt and mercury and cause weight gain. The Merck Veterinary Manual notes vitamin E deficiency in cats given large quantities of canned tuna.
Signs to watch for
- Weight gain if fed often
What to do
A bite of tuna is unlikely to be a problem. Don't make it a habit or a main meal. If your cat seems unwell after eating tuna, or eats a lot of it often, talk to your vet.
How to give it
If at all: tinned in spring water with no added salt, a little, rarely, and never instead of cat food.
Questions and answers
Can my cat live on tuna?
No. Tuna lacks essential nutrients cats need, and cats given large amounts of canned tuna have developed vitamin E deficiency.
Related foods
All foods: What can cats eat?Sources
- Cats and human foods — Cats Protection
- True or False: Milk and tuna are great foods for cats. Answer: False — VCA Animal Hospitals (no date shown)
- What should I feed my cat? — RSPCA Australia (updated 2025-11-20)
- Nutritional Requirements of Small Animals — Merck Veterinary Manual (S. L. Sanderson; reviewed 2023-11, updated 2024-09)
- Feeding Your Cat — Cornell Feline Health Center (updated 2026-04-30)
- Cat-friendly pancake recipe — PDSA (2024-02-02)
General information from the sources below, not reviewed by a vet and not a substitute for veterinary advice. When in doubt, call your vet.
How kids practise this in PetPrep
In PetPrep a child looks after a realistic cat: meals at the right times, water, walks and care. Knowing what is safe to share is part of being ready for a real pet.