Is tuna bad for cats?

Can cats eat tuna?

Cats love seafood, and most cats are especially fond of canned tuna and tuna juice. While tuna is fine for cats in moderation or as a treat, too much canned tuna can be bad for your cat. Fish is a great source of protein, but there are a few reasons why a steady diet of human-grade canned tuna can cause health problems for your cat. 

Tuna alone is not nutritionally complete, and many cats are allergic to fish. Most fish contain trace amounts of mercury, and the higher up on the food chain a fish is, the more mercury is accumulated in the fish. Tuna is relatively high on the food chain and therefore contains higher amounts of mercury than other fish, leading to an increased risk of mercury poisoning.

Tuna is also high in unsaturated fats.  While it is healthy for humans to choose unsaturated fats in their diet, too much can be bad for cats. Consuming too much tuna can cause your cat to develop a Vitamin E deficiency, leading to an inflammation of the fatty tissue, a condition known as steatitis (“yellow fat disease”).  Cats that consume large amounts of red tuna in particular are more prone to this painful condition.

Commercial canned “tuna” cat foods are not just straight tuna, but have other added ingredients, vitamins and minerals as well as the amino acid taurine, which is essential to cats.  Just make sure to feed your cat a high-quality pet food formulated for cats, and if you choose to feed your cat human-grade canned tuna, limit it to an occasional treat.

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  1. I can hardly believe that you are telling us that feed our cats with products that contain mostly fillers is better for them than 100% real fish.

  2. I have been feeding my 10 year old cat a small amount of tuna twice a day since she was a kitten with no problems at this time. Just had a full blood work panel done on her and all was very good. She is also fed a high quality dry food. Grain free and made in the USA. Her teeth are in very good shape too.

    • I like your comment Patti love it……..

    • You sound like all those people who have said “I’ve smoked for 40 years without a problem!” Your anecdotal evidence is completely arbitrary. Your cat being fine just means you got lucky. There are always people who get lucky. It doesn’t negate statistical evidence.

      By the way, your cat’s teeth being in good shape has very little to do with the food.

  3. My cat was 16 years old – We did feed her a tablespoon of canned tuna with her regular cat food and the vet said that was fine – or we could even give her the tuna water only the vet said (She didn’t like any oil) – There was no concern for mercury poisoning and I looked it up and studied it for quite a while – What did develop was hyperthyroidism – Some online details said the tuna or the cans it came in could have contributed to the hyperthyroidism – Tigger passed at 16 years old and I still don’t know if I could have done something different or even left it out of her diet even though she loved it so much : (

    • I am sorry to hear that Patti #2 cats do not live much more than that……..I have a friend who has three old ones…..they have lost all control of their bowels…..her house is a constant mess…but so is she………I know mine is in love with life as yours was…….trigger loved every day she had with you………you are a good mom……..sorry for your loss…..

  4. I am concerned my cat loves tuna…….she is 13 she does very well. mostly indoor cat she also gets treats and her dry food only two or three times a day a little tuna in water……she dearly loves it…..she is fine….should I worry…..other foods she licks the juice, and leaves the so called meat? I love to see her eat the fish………………meat…….protein……..

  5. I have been feeding my cat tuna and a high quality dry food. I would think real fish would be healthier for cats rather than typical wet cat food. The canned food has a lot of ingredients; Whereas tuna only has the fish. Not too sure about the health problems of the mercury in the tuna. Because cats are strict carnivores I would think fresh meat should be part of their normal diet; Just my opinion. My cat is 3 years old and free from any health issues.

  6. I have a 10 year old with kidney disease. He gets saline every other day, a kidney diet and a tuna flavored liquid medication. He hates the diet and liquid so I mix these in with a spoonful of tuna daily so that he will take the medicated food and liquid. If I didn’t then he would never eat the kidney food or take the liquid. Not sure if I’m doing more harm than good, but at least he’s taking the meds this way. Hopefully I’m not making this worse….

    • Julie, this isn’t on the topic of tuna, but I also have a kidney cat (diagnosed 6 1/2 years ago) and I’ve been giving him Azodyl almost the entire time, along with periodic saline as needed, and he eats regular canned cat food since he won’t touch the kidney food. Azodyl is a veterinary probiotic intended especially for cats & dogs with kidney failure, and it has helped him tremendously. He takes 3 capsules daily–2 a.m. & 1 p.m. Check it out online if you’re interested. It facilitates enteric dialysis–meaning that many of the toxins normally filtered by the kidneys are eliminated in the intestines instead via this probiotic. Not quite as efficient as the kidneys, but pretty close. It has worked really well for us. Just FYI.

  7. I have a burmese that eats dry food and seems to only want to eat “fish”; Applaws, states it all natural, Dolphin friendly, no additives, rice is added. My previous Burmese ate fresh raw steak, this one tried mince for a little bit, then i tried chicken. Although she has Science diet dry food available all day she eats minimal amounts and looks for something else occasionally. She a gets a tin 70g over two days at the most. Any suggestions on what else to try rather than “Fish”

    • Hi Wendy. A fish variety of cat food is fine. The concern is in regards to feeding large amounts of plain canned tuna which, on its own, is not a balanced diet.

  8. “wendy…SCIENCE DIET IS AWFUL FOR YOUR CAT and that is why she doesnt eat it. Cats are very smart and are as sensitive as humans. If they arent eating it then CHANGE BRANDS…They add sooo much garbage in these pet foods…do you KNOW what is going into them? READ THE LABELS and do the research,,then you will know why the cat doesnt want to eat it.

  9. My 7 year old Burmese is on a dry prescription food diet, but he recently developed a taste for tuna and since I’ve discovered that I can hide his daily heart pill in it (better than shoving a pill down his throat every day), I give him a table spoonful a day. He doesn’t like wet food (just licks the gravy off it), so perhaps I should find something of a similar texture that’s just as appealing so we can alternate.

  10. I have a 10 yr old boy and have wasted lots of money over the yrs, as he ll just walk past wet foods, some he used to eat.
    The one type he doesn’t pass up, is tuna flavors. Ill take my chances now. Hes 20 lbs, he’s on prescription dry, and to prevent him scratching or waking me up meowing for wet food, ill continue this tuna wet.
    If you have an HEB, try Fortis canned food – my boy loves that and cleans the plate. Plenty of times he’d lick only the juices up.

  11. I have a problem. My cat wont keep anything down except tuna! She is losing weight. Please help

    • I hope there has been an improvement. If your cat isnt eating enough, she will get hepatic lipidosis (skin will have a yellow tint & she will vomit bile). Catsure has helped my cat, but take her to the vet as it is a deadly condition. There are several options for treating this & getting her back to eatng normally.

  12. My past cat, Vanilla died from kidney failure. He ate can of tuna every day for 10 years. He loved it. He hate can of cat foods. So I stopped feed him with can of tuna. Then I feed him with special k-d food for 5 years. Vets told me that tuna was bad for cat. I wish I would not feed him can of tuna but he was stubborn. He always want to have can of tuna. I don’t feed my present cats with can of tuna. I feed him can of cat food with turkey and chicken. No tuna.

    • Please make sure the kitty has No-GMO food !! Means you buy Organic. Cats hunt for meat in wilderness, they do not eat cooked food… but in the wild cats eat fresh blueberries, some grass and even green peas, as these are fantastic against kidney problems :))) Please make sure the kitty eats some fresh, uncooked meat, 1-2 table spoons of non-GMO raw meat, mix with cold-press flexseed oil/ sunflower daily ~ Also add a few green raw Organic peas per day, you can buy them frozen :))) Please choose safe canned food, like Paul Newton’s canned food, even if with brown rice instead of a Carrageenan additive .
      Just mix all that together with daily canned food. I learn very hard way…. my heart is still bleeding for my gorgeous Jake, fed for years with horrible doctor’s “formula” dry food….suffering kidney bloody horrors long before I even met him…
      About 5 years ago I rescued a small kitten – browsing the streets, deadly undernourish, so very ill… He is the most healthy and happy cat right now -no medications whatsoever ~ I just wrote about his diet that works wonders 🙂
      Fresh purified water – everyday!!!
      Blessings, wishing all of you a very long sweet life !!

  13. My cat Baba was diagnosed with kidney disease 2 years ago. She would not eat the kidney food. So for the last 2 years she ate her regular dry food and tuna with water. She recently went to the vet for a check up and her blood work had returned to almost normal. The vet couldn’t believe it. The only thing different was the tuna with water. She will be 18 in January. So I take what is said about tuna with a grain of salt.

    • Thank you Laura! My cat eats tuna in spring water EVERY DAY FOR EVERY MEAL. He loves it and refuses to eat any type of wet cat food. He does eat regular dry Adult Original Science Diet cat food. We have had him now for 3 years and he is very healthy and active. We adopted him from a shelter, and he had been homeless, which is how I think he acquired the taste for tuna, as some people would have probably fed him that since he is very friendly. We think he’s about 4-5 years old now. I bought every possible brand and flavor of wet cat food at first, and he would not touch any of them! So now it’s white tuna in spring water only! With biscuits on the side. Surf & turf…

  14. My Husband insists on feeding our 17 r old cat(with kidney disease) tuna made with mayo and other additives. Usually from a tuna salad made at a restaurant. When I try to explain that this is not healthy for the cat. he gets upset at me. What are your thoughts about this practice.

    • cats should definitely not eat mayo, doesn’t matter if you husband gets upset. and 17 years old is great- but all that added salt in people food will not help

  15. guys heres a simple trick to wean your cats OFF tuna…NO tuna is safe NONE…and NO SALMON either…contaminants and pollutants our oceans is saturated in polymers…plastics environmental waste etx….BEST TO FEED SPRINGWATER SARDINES Brand BRUNSWICK they are about $1.80 per tin. GIVE 1-2 tins per week or fortnight but NO more. SARDINES ARE PERFECT Sardines are at the bottom of the aquatic food chain, feeding solely on plankton. As a result, they do not concentrate as much heavy metals like mercury and other contaminants found in most fish. HERE’S THE TRICK…start buying CHICKEN NECKS get a meat mallet and wack it to pre-crush the chicken neck bones to help kitty ‘ease into’ eating them and then roll the chicken neck in a bit of the tuna juice kitty has been used to – you may have to sprinkle a little of the tuna onto the neck – and SPRINKLE a little of NUTRITIONAL YEAST FLAKES-non active yeast (they are yellow in colour and smell a bit like cheese flavor-buy from health food store – don’t buy brewers yeast as its an active yeast and causes fermentation in the gut-owch!) If kitty still won’t eat it try throwing the neck and praising kitty for chasing it – it may take some coaching but what you’re doing is reverse psychology. NEVER give in to tuna it’s one of the most dangerous fish meat. It’s like people who have junk food have to use a lot of discipline and encouragement. REMEMBER CATS ARE CARNIVORES and MUST eat the whole carcass incl organs for optimum well being. NO PROCESSED CAT FOOD WET OR DRY can compete with raw food for cats (and dogs). PLEASE STOP FEEDING CATS TIN AND PACKET foods. And never feed a cat dog food they lack specific nutrients for cats. Farmed fish is too terrible. Not only is it unethical shooting aquatic birds that pick out farmed fish like pelicans etc they pollute and contaminate our oceans with GMO engineered fish excrement and food loft waste.The salmon are confined just like battery chickens and sows and is incredibly horrific. They are force fed and injected with SOY and PESTICIDES and many more agriculture and pharma toxins – oh yes and they are injected with dye to make it pink red again because they are so malnourished from their lifestyle…you wouldn’t buy salmon if it looked slightly grey or white would you. Well anyway guys I know you can do it stay strong and focused. Move from the isles and to the meat fridge section buy LAMB, CHICKEN, CHICKEN NECKS AND CHICKEN GIBLETS-offal. WARNING even though the lamb offal is inspected for HYDAYTID PARASITE not all is 100% CYSTS lye dormant within the organ tissue and when consumed the parasite will emerge. DO NOT FEED LAMB OR BEEF OFFAL to DOGS ESPECIALLY and CATS, CHICKEN DOESN’T’ CONTAIN THIS FATAL PARASITE.. Also don’t get caught in the trap of thinking worming your pets is ok to feed lamb and beef offal because worming is a neuro-toxin which stores in the animals body and is NOT water soluble resulting in cancer and immune suppression diseases either chronic or acute. REMEMBER GUYS SARDINES. ARE BEST either fresh and pan fry in coconut oil or brunswick in NO ADDED SALT Springwater. You can get the olive oil one but it has salt. NEVER buy food with added salt EVER. PS…AVOID ALL PET FOOD FRESH MEAT IT IS LACED WITH SULPHITES which seriously depletes Vit B1 in felines and dogs and is a high carcinogen. SULPHITES must never be fed to pets. ALL ROO meat is a disgusting meat and is also laced with poisons. Propaganda will tell you otherwise. MERCURY is in SHARK (FLAKE), COD, SALMON, PREDATORY FISHES AND YES TUNA. Even cat food tuna contains heavy metals.

  16. Thanks Eve. Yes my cat will only eat canned cat-food tuna (I’ve tried about 10 other wet cat food brands) but this past year has been starting to act so strange that I’ve been wondering if it’s from the mercury in the tuna…as I know it goes right to the brain. I’ve been reading that there is a lot more mercury in fish nowadays then they’ve let on…and even more than 10 yrs ago…and tuna has some of the highest mercury levels. My cat has started to become paranoid and fearful…even scared of a sock or my purse when on the floor…even gets scared of a blanket when I am just spreading it out a little….to the point where he won’t go near it again. I’ve tried chicken …and also sardines…but he wouldn’t touch it.

  17. Boy Eve that almost makes me wish I didn’t have two cats. you are making it sound way too complicated to feed them. I have chronic pain and have trouble even feeding myself. I feed my cats dry purina food and friskies canned cat food is what I fed my other cat who lived sixteen years. Maybe healthier people can do all that but this 65 year old arthritic cannot.

  18. nobody feeds their cats perfectly. im sure we all wish we knew how to make them live forever… the important thing is they are loved, safe, sheltered and fed. do the best you can and dont be hard on yourselves. just love em up!

  19. I have a 4 year old cat , that is now 18lbs , i got him from the shelter an the whole first week she would not eat the dry food, only nibbled 4 or 5 pieces, he had alot of dental work so i thought maybe the dry was to hard, i tried caned cat food an i noticed he ate a small portion, an licked all juice , he wont drink water or milk , an after a family gathering, i noticed he went through the trash an ate chicken an chicken bones, this cleared up about the dental work not being so bad , but he wont eat his food , some one suggested tuna in water , an i gave him a can an he cleaned the plate , i was so happy to see him eat , so i ran out an got 10 more cans of tuna , an ive been feeding him tuna twice a day for a month now, i never knew tuna was bad, now i dnt know what to do , should i just take it all away,

  20. Very interesting thread. I was actually looking up whether it would be ok to give my two cats tuna in brine instead of tune in spring water as I had none of the other, they only have it as a treat but usually daily. After reading this I will certainly make it just a rare occasion now and not daily, I didn’t realise the dangers!

  21. I mix a small teaspoon of albacore canned tuna in water into high-end wet food. They love it! One can will last a long time. Add water to the can of tuna to keep it nice and wet and keep it tightly sealed and in the fridge.

  22. “limit it to an occasional treat”. Vague statements do not provide guidance to cat owners. How often is too often? How much is too much? Should the amount of tuna per week be based on the weight of the cat or is weight irrelevant? Is there a difference in consumption amount for males versus females (our boys love tuna, not as much for the girls)?

    We typically give half a can of tuna to each cat once per week, usually Sunday as a treat; however, the women in the family tend to treat the cats more often, especially if the cats turn up their nose on other wet food. Although it’s half a can per cat, some don’t eat all their tuna while others go foraging later to eat what others left behind. When I feed them tuna, I add filtered water to make it soupy. All the cats like the tuna soup better than they like the tuna (they drink all the juice and leave behind some of the tuna flakes). Alas, the women in my family just don’t get why water should be added or they think it is too much bother (gee, they can open a can, dish it out, but can’t manage to stir in some water).

    But again, “limit it to an occasional treat” gives no clue as to how often the cats should get the tuna treat and how much they get for each treat time. I have a feeling that not much is really known so the suggestion is just a guess.

  23. I fed my cat bee tuna fish in a can labeled no gmos is that ok

  24. Yesterday I discovered a cat living outside on our street and have been feeding it human food (chicken nuggets milk taco meat and cooked steak) I’m worried that human food will hurt it so I want to make some homemade cat food or treats. I thought tuna would be good in a cat treat with whole wheat flour and then baked but now that I have read your post I am having second thoughts. Is tuna baked inside homemade cat treats bad? Should I make something else? If so what would you recommend?

  25. My cat is taking medicine and the only way I can get him to take it is to crush it up in tuna. Is this bad for him?

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