Is tuna bad for cats?

A steady diet of human grade tuna is not healthy for cats.

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.

Commercial canned “tuna” cat foods are not just straight tuna, but have other added ingredients. The added vitamins, minerals, and the amino acid taurine (which is essential to cats), make the food nutritionally complete for your cat. Additionally, although cats may develop a craving for tuna, many cats are sensitive or allergic to fish.

Tuna is high in unsaturated fats.

While it’s healthy for humans to choose unsaturated fats in their diet, too much is unhealthy for cats. Consuming too much tuna can cause your cat to develop a Vitamin E deficiency. This may lead 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.

Tuna is higher in mercury than other 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, resulting in an increased risk of mercury poisoning. In particular, canned white tuna (albacore) has mercury levels almost three times higher than skipjack tuna (light tuna).

What should you feed your tuna-loving cat? Make sure the basis of your cat’s diet is a high-quality pet food formulated specifically for cats. Healthy, grain free canned cat foods such as Taste of the Wild Rocky Mountain Feline Formula or Blue Buffalo Wilderness have salmon as the first ingredient and may satisfy your cat’s craving for fish.

If you choose to feed your cat human-grade canned tuna, limit it to an occasional treat. Try to choose “chunk light” tuna in water rather than “white” tuna. Better yet, consider a healthy cat treat such as Grizzly Salmon Fillet Treats, or PureBites which are freeze-dried, single ingredient treats.

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  1. Reading alot of comments and Im surprised at the amount of folks who question other peoples choices. At the end of the day so long as you have a happy AND healthy cat that’s all that matters. I’ve always had cats along with many other animals, the benefit of growing up on a farm, and I can say I didnt always know what they ate. They hunted rabbits, mice, and yes birds. These where the happiest and healthiest cats I have ever know. Now I live with my boyfriend away from the farm and we have two indoor rescue cats. One who is old and eats senior cat food and the other is 3yr. I have to control his diet to the extreme as he is prone to blockage which could kill him. (Very scary when it happens, and sometimes he fakes the symptoms to let us know whose in charge) . Due to this he has to have a very low protein diet, which is where I am surprised at some of you feeding the ‘better quality cat foods’. The protein content on some of these high priced ‘better quality’ foods can be as much as 70%. This may sound brilliant but believe me I almost lost my black bear last year due to high protein cat food, it was traumatic for both cats and both humans. He has for the past 12 months been on specialist vet WET cat food to keep him alive. Dry food is a massive no no in my vets opinion. He did say the tablets we had to give Louie could be ground down and mixed in with tuna in spring water but no more than a teaspoon of tuna to be given. So what Im saying is what you might think is best for your cat might not be the case. Dont get fooled by these over priced ‘holistic or natural’ cat foods, its all marketing at the end of the day. Speak to YOUR vet who knows YOUR pet and if you give treats do so but always in moderation. Old bear as his treat gets a handful of cat biscuits because he enjoys them and helps keep plaque down on his teeth also gives more fibre to help with hairball control. Louie only gets wet food and for his treat on Friday he gets a some tuna with tuna water.

  2. Make their food, then you can control what goes in their bodies. Just made my batch for the week which included 2 1/2 pounds of barely cooked chicken thighs, pumpkin, rice, oil, and a can of white tuna in water to make it yummy to them. Am transitioninng to a raw diet after my male cat had urinary tract issues from him not wanting to drink enough water. Will transition to almost raw, it’s what’s best for them. Once I can obtain a grinder, they will transiton to mostly raw. Their homemade food has yielded softer coats and happier kitties. And it costs only a little more than store-bought cat food. Totally worth it.

  3. I fed both of my cats starkist tuna in water. One lived 22 years, the other 18 years with zero health issues. That was their daily diet , nothing else. My new guy, same problems. I’m sticking with what had worked for me and my guys 💕

  4. I have 2 kittens and have been giving them a can divided into 4 a day, they both eat half a can a day, and they also drink plenty of water and they eat dry food. I have other cats that hate tuna so this is new to me. Is half a can per day bad for them?

  5. Patti #2 Even if it could have gave your cat another few months or a year- I think you did good by giving him 16 years of delicious meals instead of 17 years of flavorless meals. Your cat would have definitely chosen the former. Your job as a cat mom is not merely to prolong the life of your loved one but more importantly contribute to the overall quality of his/her life.

  6. I feed my cat about 3-4 full tins of tuna in spring water, she is 17 and is a very fussy eater. Put tuna down and she takes the lot without any major health issues so unfortunately I think it depends on the individual cat. She will be 18 shortly unless I strangle her for waking me up for a cuddle.

  7. My cat refuses to eat any canned cat food from the store. Perhaps not unrealistically, because all that food smells like hell, don’t know what the companies put in that stuff. And both my cats are picky, they won’t eat bad tasting stuff.. My little one love tuna, people food, that’s expensive too. But, at least it tastes ok, my baby east it all.

  8. I feed my baby(cat) chunk light tuna in water. Occasionally. I don’t believe occasionally will harm hrm. He’s four years old and has no apparent health issues regarding occasionally feeling him tuna. Once again I said”occasionally” I myself wouldn’t eat tuna from can unless I really needed food. I use to eat sushi and sashimi and realized thing’s like. Parasites, heavy metals like aluminum and Mercury. I actually try not to eat anything in aluminum like foods in aluminum can’s especially acidic foods. Antiperspirant is another product I don’t use bc the first ingredient in all antiperspirant is aluminum (next time read antiperspirant active ingredient. As an alternative I use deodorant bc there is no aluminum in deodorant. One day I took a bit of tuna from the can and it had a metallic tastes to it. That’s probably bc it’s been in that aluminum can for years. Finally people educate themselves not to only what their pets consuming but as to what they are are consuming themselves everyday. Reason being if you’re not healthy how can you possible that care of something else that you love and care about. We must love ourselves before we can love anything else
    Makes perfect sense to me. Stay healthy and happy and Remember the mind and body work as one unit . If the mind isn’t functioning properly than this effects the body vise versa. Good luck in the future. Education is everything.

  9. My cat is 4, and a very fussy eater when it comes to shop bought cat foods, be it a tin or a pouch, and personally I dont blame her, the stuff stinks and its completely reformed meat, you dont actually know what is in there.
    Skye gets 3/4 of a tin of tuna in spring water every evening for her dinner, and throughout the day she has access to a full bowl of fresh water and a bowl of good quality dry kibble that she eats when she wants (and generally the bowl is empty by the end of the day) .
    My Vet says he is always very impressed with her condition, she is a house cat, 8 and a half pounds, a big girl for a female, but is NOT fat, shes actually very lean, which I attribute to her Tuna/kibble diet, and he always commends me on her bright clear eyes, shiny coat and body condition.
    Whereas my brothers housecat would literally eat anything, she loves food, but any human food, or any kind of strong high protein content foods such as Tuna, red meats ect. does not agree with her stomach, and so she is on a diet of a mixture of wet pouch cat food and the same dry kibble as my cat mixed together in a bowl and a drizzle of water over the top to encourage her to consume more water as she wouldnt be a big drinker. She gets this twice a day, in the morning and at night, with strictly no kibble left out during the day. Of course both get the odd few treats though 😊

    Two very different diets and routines for two very different cats

    So, I do generally think, you know your own cat the best, feed them what you feel is best for them and what they like, because allergies, and all of the above that this article speaks about really depends on the cat. They are like people, every cat is individual and different, and all react differently to different diets. For one cat it may be the best diet on the earth, like for mine, and for others, like my brothers, it may not.

    My advice is to listen to your cat, and feed them what keeps them happy and healthy, tuna or not.

  10. My three cats get all the dry food they want and 1/3 a can of tuna each every morning. They are all happy and healthy. Although the 17 year old cat drinks and pees a lot of water. Another blog suggested that the Kidneys or liver isn’t absorbing water right but by drinking a lot of water allows her to get enough. Old age sucks. Note it’s hard to sleep late with cats waiting for breakfast treat.

  11. I have a 15 year old stay cat and after all these years of feeding her she ihas been turning her noise up at everything I feed her. I tried everything and tuna has been the only thing she will eat but now she is loosing her hair. Could that be from eating canned tuna?

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