Can dogs eat tuna?
✓ Reviewed against PDSA, Blue Cross & Animal PoisonLine guidance · Last updated: 2026-06-17
How we keep this site free. Some links on this page take you to Amazon or other online retailers (including vet pharmacy partners Best Vet Care and Canada Pet Care via CJ Affiliate). As an Amazon Associate and CJ publisher we may earn a commission at no extra cost to you.Full disclosure.
The full picture
Tuna is safe for dogs in small amounts but isn't ideal as a regular food. As a large predatory fish, it accumulates mercury in its flesh, and frequent tuna consumption can lead to mercury poisoning over time — especially in smaller dogs. Tinned tuna is safest if it's in spring water, not brine (too much salt) or oil (unnecessary fat). Fresh tuna should be cooked plain. It's a useful 'emergency protein' if you've run out of dog food, but don't make it a habit. Salmon or sardines are better regular choices.
Check individual ingredient safety at 247IngredientsCheck.
If your dog ate more than a safe amount
For a small accidental taste, watch for vomiting, diarrhoea, or signs of discomfort over the next few hours. For a large amount or if your dog is small or has existing health conditions, call your vet. When in doubt, call the ASPCA Animal Poison Control Center on (888) 426-4435.
Risks to watch for
- Mercury accumulation over time
- Excess salt from brine varieties
- Excess fat from oil-packed varieties
Potential benefits
- High-quality protein
- Omega-3 fatty acids
- Most dogs love it
Safe portion size
A tablespoon once or twice a month for a medium dog.
Safer alternatives
- salmon
- plain tinned sardines in spring water
Does size or breed matter?
No specific breed sensitivity to plain, cooked tuna. Portion should scale with body size — smaller dogs need smaller amounts both for calorie control and because any mercury or sodium content (relevant for tuna and some preserved fish) has proportionally more impact on a smaller body. Always check for and remove shells or bones before serving.