Can Cats Eat Tuna? Short answer: Yes — cooked or canned tuna (in water, no salt) is safe in VERY small amounts as an occasional treat. But tuna is NOT a complete diet and has significant risks.
Cats love tuna. The smell and taste are irresistible to most felines. But too much tuna — or the wrong kind — can cause serious health problems.
The main concerns: mercury poisoning (tuna is a large predatory fish that accumulates mercury), addiction (cats may refuse balanced cat food), thiaminase (in raw tuna — destroys vitamin B1), high sodium (canned tuna in brine), and malnutrition (tuna lacks taurine and other essential nutrients).
I’m Dr. Allona Jackson, DVM. In this guide, I’ll explain safe portions (very small), cooked vs raw vs canned, mercury risks, addiction, and much healthier alternatives.
For a complete list of safe and toxic foods, see our Cat Food Safety Guide — your pillar resource for everything your cat can and cannot eat.
For detailed information on raw fish risks, see Can Cats Eat Raw Fish.
Quick Answer — Cooked or Canned (Water, No Salt), Tiny Amounts Only
| Rule | Detail |
|---|---|
| ✅ Cooked fresh tuna (plain, no oil, no salt) | Safe in tiny amounts (1 tablespoon, 1x per week) |
| ✅ Canned tuna in water (no salt added) | Safe in tiny amounts (1 tablespoon, 1x per week) — drain water |
| ❌ Canned tuna in brine (salt water) | High sodium → salt poisoning risk |
| ❌ Canned tuna in oil | High fat → pancreatitis risk |
| ❌ Raw tuna | Thiaminase (destroys vitamin B1) + bacteria + parasites |
| ❌ Tuna juice / brine | High sodium — don’t pour over food |
| ⚠️ Mercury risk | Tuna is a large predatory fish — accumulates mercury |
| ⚠️ Addiction risk | Cats can become “tuna junkies” — refuse balanced cat food |
| ⚠️ Malnutrition risk | Tuna lacks taurine (causes heart/blindness) and other nutrients |
| 📏 Portion size | 1 tablespoon (about 15g), 1 time per week maximum |
| 🍽️ Preparation | Cooked: bake/boil/steam, no seasoning. Canned: in water, no salt added, drain well. |
| 🐱 Kittens | Avoid — focus on kitten food |
| 🐱 Senior cats | Limit — mercury risk accumulates over time |
| 🚨 Emergency | If tuna causes choking (bones) or allergic reaction → call vet |
Is Tuna Toxic to Cats?
No — tuna is not toxic to cats.
However, tuna has multiple significant risks that make it dangerous when fed too often or in the wrong form.
| Concern | Verdict |
|---|---|
| Toxicity | None — tuna is not poisonous |
| Mercury poisoning | Real risk with frequent feeding (once per week is generally safe for healthy adults; more often = risk) |
| Thiaminase (raw tuna) | Destroys vitamin B1 → neurological damage |
| Addiction | Cats can refuse all other food — leads to malnutrition |
| Malnutrition | Tuna lacks taurine (blindness, heart failure), vitamin E, and other nutrients |
| High sodium | Canned tuna in brine is dangerous (salt poisoning) |
| High fat | Tuna in oil is dangerous (pancreatitis) |
Dr. Jackson’s note: “Tuna is like candy for cats. They love it, but it’s not good for them. A tiny bit once a week as a special treat is fine. But feeding tuna daily — or worse, as a main diet — will cause serious health problems.”
The Mercury Problem — Tuna Is a Large Predatory Fish
| Fact | Detail |
|---|---|
| What is mercury? | A heavy metal that accumulates in the tissues of large predatory fish |
| Why tuna has mercury | Tuna eat smaller fish that contain trace mercury. Mercury biomagnifies up the food chain. |
| Which tuna has most mercury | Albacore (white) tuna > Skipjack (light) tuna > Canned light tuna (skipjack) has less |
| Symptoms of mercury poisoning in cats | Neurological signs: ataxia (stumbling), tremors, blindness, abnormal behavior, kidney damage, death |
| Safe amount | 1 tablespoon once per week is generally safe for healthy adult cats. More frequent feeding = higher risk. |
| Who is most at risk | Kittens (developing nervous system), pregnant cats, cats fed tuna long-term |
Mercury levels in tuna (approximate):
| Tuna type | Mercury level | Risk for cats |
|---|---|---|
| Albacore (white) tuna | Highest | Avoid |
| Yellowfin tuna | High | Limit severely |
| Skipjack (light) tuna | Lowest | Safest option if feeding occasionally |
| Canned light tuna (skipjack) | Lowest | Safest option |
Dr. Jackson’s note: “Mercury accumulates in the body over time. A tablespoon of tuna once a week for a year adds up. If you feed tuna, choose skipjack/light tuna over albacore/white tuna, and keep portions tiny.”
The Addiction Problem — Tuna Junkies
| Fact | Detail |
|---|---|
| Why cats love tuna | High protein, strong smell, umami flavor — evolutionary preference for fish |
| What happens | Cats fed tuna regularly may refuse to eat their balanced cat food |
| Consequences | Malnutrition (taurine deficiency, vitamin E deficiency, calcium deficiency) |
| How to prevent | Limit tuna to 1 tablespoon once per week. Never use tuna as a meal replacement. |
| How to break addiction | Gradual transition back to cat food (mix tiny amounts of tuna with cat food, slowly reduce tuna). May take weeks. |
Dr. Jackson’s note: “I’ve seen cats who refuse to eat anything but tuna. They become malnourished, develop heart disease from taurine deficiency, and can go blind. Don’t create a tuna junkie. Keep tuna as a rare treat.”
The Malnutrition Problem — Tuna Is Not Complete Food
| Nutrient | Does tuna have it? | Why cats need it |
|---|---|---|
| Taurine | Very low (destroyed by processing) | Essential — deficiency causes blindness, heart failure |
| Vitamin E | Low | Deficiency causes steatitis (painful inflammation of fat tissue) |
| Calcium | Very low | Deficiency causes bone problems |
| Vitamin A | Low | Cats need preformed vitamin A |
| Arachidonic acid | Low | Essential fatty acid for skin and coat |
The bottom line: Tuna is NOT a complete food for cats. It should never be fed as a meal replacement. It is a rare treat only.
Forms of Tuna — Safety Guide
| Form | Safe for cats? | Notes |
|---|---|---|
| Cooked fresh tuna (plain, no oil, no salt) | ✅ Yes (tiny amounts) | Bake, boil, or steam. No seasoning. |
| Canned tuna in water (no salt added) | ✅ Yes (tiny amounts) | Drain water. Choose skipjack/light tuna over albacore. |
| Canned tuna in water (with salt) | ⚠️ Caution | High sodium — not recommended |
| Canned tuna in brine | ❌ No | Very high sodium — salt poisoning risk |
| Canned tuna in oil | ❌ No | High fat → pancreatitis risk |
| Raw tuna | ❌ No | Thiaminase (destroys vitamin B1) + bacteria + parasites |
| Tuna juice / brine | ❌ No | High sodium — don’t pour over food |
| Tuna sushi / sashimi | ❌ No | Raw + may have seasonings |
| Tuna jerky / dried tuna | ⚠️ Caution | High sodium, chewy (choking) |
| Tuna cat food (commercial) | ✅ Yes (as directed) | Nutritionally balanced, safe for regular feeding |
How to Safely Feed Tuna to Cats
Step 1: Choose the right tuna
| Do ✅ | Don’t ❌ |
|---|---|
| Cooked fresh tuna (plain) | Raw tuna (thiaminase risk) |
| Canned tuna in water (no salt added) — skipjack/light tuna | Canned tuna in brine (salt poisoning) |
| Drain water from canned tuna | Canned tuna in oil (pancreatitis risk) |
| Limit to 1 tablespoon | Albacore (white) tuna (higher mercury) |
Step 2: Prepare properly
| Step | Instruction |
|---|---|
| 1 | Cook fresh tuna thoroughly (bake, boil, or steam — no oil, no salt, no seasoning) |
| 2 | For canned: choose water-packed, no salt added. Drain water completely. |
| 3 | Flake into small pieces (remove any bones) |
| 4 | Measure 1 tablespoon (about 15g) |
| 5 | Serve as an occasional treat — never as a meal |
Step 3: Portion control
| Cat type | Portion | Frequency |
|---|---|---|
| Healthy adult cat | 1 tablespoon | Once per week maximum |
| Kitten (under 1 year) | ❌ Avoid | Mercury risk to developing nervous system |
| Senior cat | 1 tablespoon | Once per week (limit — mercury accumulates) |
| Overweight cat | 1 tablespoon | Once per week (low calorie, but treat only) |
| Pregnant cat | ❌ Avoid | Mercury risk to fetus |
| Cat with kidney disease | ❌ Avoid | High phosphorus, potential salt |
Step 4: Observe your cat
| Response | Action |
|---|---|
| Eats eagerly, no issues | Fine — limit to once per week |
| Refuses regular cat food after tuna | Tuna addiction — stop feeding tuna immediately. Transition back to cat food. |
| Vomiting or diarrhea | Possible intolerance — discontinue |
| Lethargy, stumbling (mercury poisoning — very rare) | Emergency vet |
Special Cases — Kittens, Seniors & Cats with Health Conditions
Kittens (under 1 year)
- ❌ Avoid completely
- Mercury risk to developing nervous system
- No nutritional benefit (kittens need balanced kitten food)
- Recommendation: No tuna for kittens
Senior cats (10+ years)
- ⚠️ Use caution — 1 tablespoon once per week maximum
- Mercury accumulates over a lifetime — seniors may have higher body burden
- Higher risk of kidney disease (tuna is high in phosphorus)
- Recommendation: Limit or avoid
Pregnant or nursing cats
- ❌ Avoid completely
- Mercury can cross the placenta and affect fetal development
- Recommendation: No tuna
Cats with kidney disease
- ❌ Avoid — tuna is high in phosphorus (bad for kidneys)
- Canned tuna also has sodium (even “no salt added” has natural sodium)
- Recommendation: No tuna
Cats with pancreatitis history
- ❌ Avoid tuna in oil (high fat)
- Plain cooked or water-packed tuna in tiny amounts may be safe, but better to avoid
- Recommendation: Avoid
Cats with IBD or chronic digestive issues
- ⚠️ Use caution — some cats are sensitive to fish
- Recommendation: Small amount (1 tsp) as test
Overweight cats
- ✅ Safe in tiny amounts (1 tablespoon once per week is low calorie)
- Recommendation: Fine as occasional treat
What If My Cat Ate Too Much Tuna?
Step 1: Identify what and how much
| Scenario | Risk level | Action |
|---|---|---|
| 1 tablespoon (safe portion), healthy cat | Low | No action needed |
| 2-3 tablespoons (one time) | Low (mercury not immediate) | Monitor. Skip tuna for several weeks. |
| Whole can of tuna (one time) | Medium (sodium/fat) | Monitor for vomiting, diarrhea. Call vet if concerned. |
| Tuna in brine (any amount) | Medium-High (salt poisoning) | Call vet — monitor for thirst, vomiting, tremors |
| Tuna in oil (any amount) | Medium-High (pancreatitis risk) | Monitor for vomiting, lethargy. Call vet if symptoms appear. |
| Raw tuna (any amount) | Medium (thiaminase, bacteria) | Monitor for neurological symptoms (stumbling, head tilt) over 2-4 weeks |
| Daily tuna for weeks/months | High (mercury, addiction, malnutrition) | Call vet — blood work recommended |
| Kitten or senior ate tuna | Medium | Call vet for guidance |
Step 2: Monitor for symptoms
| Symptom (mercury poisoning — long-term) | Timeframe | Action |
|---|---|---|
| Stumbling, ataxia | Weeks to months | Call vet — blood work |
| Tremors | Weeks to months | Call vet |
| Blindness | Weeks to months | Call vet |
| Symptom (salt poisoning) | Timeframe | Action |
|---|---|---|
| Excessive thirst | 1-6 hours | Call vet |
| Vomiting | 1-6 hours | Call vet |
| Tremors, seizures | 2-12 hours | Emergency vet |
| Symptom (pancreatitis) | Timeframe | Action |
|---|---|---|
| Vomiting | 2-12 hours | Call vet if >2 episodes |
| Lethargy | 2-12 hours | Call vet immediately |
| Abdominal pain (hunched posture) | 2-12 hours | Emergency vet |
Step 3: Call if concerned
| Helpline | Phone Number |
|---|---|
| Pet Poison Helpline | 855-764-7661 |
| Your local veterinarian | (keep on your fridge) |
For detailed emergency protocol: What to Do If Your Cat Eats Something Toxic
Healthier Alternatives to Tuna for Cats
| Alternative | Why it’s better | Full guide |
|---|---|---|
| Plain cooked chicken | High protein, no mercury, no addiction risk | Can Cats Eat Chicken |
| Plain cooked turkey | Same as chicken | Can Cats Eat Turkey |
| Plain cooked salmon | Lower mercury than tuna (wild salmon best) | Can Cats Eat Salmon |
| Plain cooked eggs | High-quality protein, no mercury | Can Cats Eat Eggs |
| Commercial cat food (fish-based) | Nutritionally balanced, safe for regular feeding | N/A |
| Freeze-dried fish treats (commercial) | Controlled portions, no mercury concerns | N/A |
For a complete list of safe human foods: Cat Food Safey Guide — Safe Foods Table
FAQs About Can Cats Eat Tuna
| Question | Answer |
|---|---|
| Can cats eat tuna? | Yes — in very small amounts (1 tablespoon, once per week maximum). Cooked or canned in water (no salt added). |
| Can cats eat canned tuna? | Yes — but only in water, no salt added. Drain water. Skipjack/light tuna is better than albacore. |
| Can cats eat tuna in oil? | No — high fat causes pancreatitis risk. |
| Can cats eat tuna in brine? | No — high sodium causes salt poisoning. |
| Can cats eat raw tuna? | No — thiaminase destroys vitamin B1, causing neurological damage. Also bacteria and parasites. |
| Is tuna good for cats? | No — it lacks taurine and other essential nutrients. It’s a treat only, not a meal. |
| Can cats be addicted to tuna? | Yes — cats can become “tuna junkies” and refuse balanced cat food, leading to malnutrition. |
| Can cats get mercury poisoning from tuna? | Yes — with frequent feeding (more than once per week). Mercury accumulates over time. |
| How much tuna can a cat eat? | 1 tablespoon (about 15g), once per week maximum. |
| Can kittens eat tuna? | No — mercury risk to developing nervous system. Focus on kitten food. |
| Can senior cats eat tuna? | In small amounts (1 tablespoon once per week), but limit due to mercury accumulation and kidney concerns. |
| My cat only wants tuna — what do I do? | Stop feeding tuna immediately. Gradually transition back to cat food (mix tiny amounts of tuna with cat food, slowly reduce tuna). |
| What’s better — tuna or salmon for cats? | Salmon (wild, cooked) has lower mercury and better fatty acid profile. Both should be occasional treats only. |
Conclusion
Here’s what you need to remember about cats and tuna:
| Do ✅ | Don’t ❌ |
|---|---|
| Feed cooked fresh tuna or canned tuna in water (no salt added) — 1 tablespoon, once per week maximum | Feed tuna daily or as a meal replacement (malnutrition, mercury) |
| Choose skipjack/light tuna over albacore/white tuna (lower mercury) | Feed tuna in brine (salt poisoning) or oil (pancreatitis) |
| Drain water from canned tuna | Feed raw tuna (thiaminase, bacteria, parasites) |
| Limit to an occasional treat | Pour tuna juice/brine over cat food (high sodium) |
| Consider healthier alternatives (cooked chicken, turkey, eggs) | Create a “tuna junkie” who refuses balanced cat food |
The bottom line: Tuna is safe for cats in very small amounts — 1 tablespoon (about 15g), once per week maximum. Cooked fresh tuna or canned tuna in water (no salt added, drained) is the safest form.
However, tuna has significant risks: mercury poisoning (with frequent feeding), addiction (cats may refuse other food), malnutrition (tuna lacks taurine), thiaminase (in raw tuna), and high sodium (in canned brine).
Tuna is a treat, not a meal. It should never replace balanced cat food.
If your cat loves tuna: Feed a tiny amount once a week as a special treat. Choose skipjack/light tuna over albacore. Cook fresh tuna or use water-packed, no-salt-added canned tuna.
Better, healthier treats for cats: Plain cooked chicken, plain cooked turkey, plain cooked eggs, or commercial cat treats.
Bookmark our Cat Food Safety Guide for all 54 foods — it’s your complete resource for feeding your cat safely.
Your cat depends on you to feed wisely. You’ve got this.
- ✅ Vet-reviewed by Dr. Allona Jackson, DVM — 2026
- 📅 Last updated: April 2026
- ⚠️ Disclaimer: This content is for informational purposes only and does not constitute veterinary medical advice. Always consult a licensed veterinarian for diagnosis and treatment of your pet’s specific condition. In an emergency, call your vet or a pet poison helpline immediately.
- 🔗 Back to pillar: Cat Food Safety Guide
- 🔗 Emergency: Pet Poison Helpline: 855-764-7661
