Occasional plain tinned tuna in spring water (not brine or oil) is usually safe as a treat. Tuna should not replace complete cat food — daily feeding causes nutritional problems.

Can cats eat tinned tuna every day?

No — daily tuna lacks essential nutrients cats need and can cause mercury accumulation and 'tuna addiction' where cats refuse balanced food.

Can kittens eat tuna?

Kittens need complete kitten food for growth. Plain tuna alone does not provide balanced nutrition — ask your vet before offering any human food to kittens.

Is tuna in brine or oil safe for cats?

Avoid brine (high salt) and oil (high fat). Choose plain tuna in spring water with no added salt — drain well and offer small amounts only.

Cat Health

Can Cats Eat Tuna UK?

Quick answer

**Occasional plain tinned tuna in spring water** is usually fine as a treat. **Do not feed tuna daily** — it is not nutritionally complete, can cause mercury build-up over time, and some cats become fixated and refuse proper cat food.

Key takeaways

Occasional plain tinned tuna in spring water (not brine or oil) is usually safe as a treat. Tuna should not replace complete cat food — daily feeding causes nutritional problems.
No — daily tuna lacks essential nutrients cats need and can cause mercury accumulation and 'tuna addiction' where cats refuse balanced food.
Kittens need complete kitten food for growth. Plain tuna alone does not provide balanced nutrition — ask your vet before offering any human food to kittens.

The full picture

Causes, home monitoring, treatment options and the exact signs that mean call your vet — in the complete guide.

Read the full guide Check symptoms

Frequently Asked Questions

Can cats eat tuna?: Occasional plain tinned tuna in spring water (not brine or oil) is usually safe as a treat. Tuna should not replace complete cat food — daily feeding causes nutritional problems.
Can cats eat tinned tuna every day?: No — daily tuna lacks essential nutrients cats need and can cause mercury accumulation and 'tuna addiction' where cats refuse balanced food.
Can kittens eat tuna?: Kittens need complete kitten food for growth. Plain tuna alone does not provide balanced nutrition — ask your vet before offering any human food to kittens.
Is tuna in brine or oil safe for cats?: Avoid brine (high salt) and oil (high fat). Choose plain tuna in spring water with no added salt — drain well and offer small amounts only.

Reviewed 2026-06-25 against UK veterinary guidance · Information only — not a substitute for seeing your vet.