Can Cats Eat Tuna?

With limitsMild effects expected
Verdict for cats: Caution · Evidence: H · Last verified: 2026-11-01 (seed data — veterinary review pending)

Only in small amounts, prepared the right way. Tuna is not poisonous to cats, but it has real downsides. It contains mercury (bioaccumulation) and thiaminase in raw tuna destroys vitamin B1. Follow the limits below and watch for stomach upset.

Why only in moderation

mercury (bioaccumulation) · thiaminase in raw tuna destroys vitamin B1

Which parts are the problem?

No specific part is singled out by our sources — treat the whole food with the stated caution.

Dose & exposure rules

No acute toxic dose; risk is chronic feeding (mercury; B1/taurine imbalance)

If it must be on the menu: safe preparation

Occasional small amounts of plain cooked tuna; never a staple

Symptoms to watch for

usually none acutelychronic: neurological signs from B1 deficiency

Chronic

What to do now

Occasional treat is fine; vet about a tuna-heavy diet

✔ Reviewed against VCA · International Cat Care. Veterinary review pending — this page will carry a named, licensed veterinarian's sign-off after review (see team and editorial policy). General information only, not veterinary advice.

FAQ

How much tuna can a cat eat?

No acute toxic dose; risk is chronic feeding (mercury; B1/taurine imbalance)

What are the signs of tuna problems in cats?

Watch for: usually none acutely; chronic: neurological signs from B1 deficiency. Chronic

What should I do if my cat ate tuna?

Occasional treat is fine; vet about a tuna-heavy diet

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