In the simplest terms, fish oil for cats involves giving your cat a supplement of oil from fish.
Theoretically, it can be as simple as that!
Fish oil supplements for cats can provide needed nutrition and vitamins that older cats may be deficient in. It can also be beneficial for some skin ailments and other health issues that an unwell or elderly cat may face.
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The Benefits Of Fish Oil For Cats
Possible benefits of fish oil for cats may include:
- Full of vitamins and minerals
- Supplements your cat’s fatty acid intake
- Can help to protect older cats from dementia
- Assists with cats dealing with kidney conditions
- A popular treatment for skin conditions
Fish Oil For Cats FAQs
Our readers often ask these questions about the popular supplement.
- Can I give my cat fish oil for dry skin?
- Does fish oil help cats with kidney disease?
- Can you give cats human fish oil supplements?
- What kind of fish oil supplement is best for cats?
What Is Fish Oil For Cats?
Have you seen fish oil for cats either on the shelves at the pet store or advertised online?
Did it leave you wondering if you should be supplementing your cat’s diet with fishy treats?
You don’t need to be a cat owner to know that there’s a lot of healthy eating buzz around oily fish.
Oily fish such as trout, salmon, sardines, mackerel, tuna, herring, anchovies and whitebait, are packed with vitamins and minerals, and a rich source of fatty acids, including the famous omega-3 fatty acids.
Fish oil supplements can then be given to cats as part of a comprehensive and nutritious diet.
Is Fish Oil Good For Cats?
Fish oil supplements have a number of uses and potential benefits.
It sounds basic, but with any supplement, the first thing to consider whether it will actually be absorbed by your cats gut and go on to reach the organs it was supposed to.
Or will it just pass straight through and land in the litter tray a day later?
Intent on answering the same question, researchers at Utrecht University in the Netherlands checked blood samples from cats eating a fish oil based diet compared to cats eating a sunflower oil based diet.
They found that when cats ate a diet supplemented with fish oil there were more of the the fatty acids eicosapentaenoic acid, arachidonic acid, α-linolenic acid, oleic acid, palmitic acid and myristic acid in their blood plasma.
So we can see that the good stuff is getting into their circulation.
They also compared the total cholesterol in the the blood stream for both groups, and found no difference between the fish oil and the sunflower oil group.
Health Benefits
Fish oil is frequently used as a nutritional supplement, to boost the intake of Omega-3 fatty acids. The oil is comprised of as much as one-third fatty acids, making this very efficient.
On the whole, healthy cats eating a high-quality, well-balanced diet are unlikely to become deficient in fatty acids. So if your cat is already young and healthy, fish oil can’t somehow make them younger and healthier.
But for older cats and some unwell cats, it could really help them out.
As listed below, it is used for a number of different issues in cats. Some of these include helping cats with kidney disease, urinary tract problems, and skin issues.
We also know that supplementing dogs’ diets with omega-3 fatty acids could protect them from heart attacks, although we’re waiting on an analogous study in cats.
Is Fish Oil Safe For Cats?
Fish oil supplements are used quite widely, because of their many health benefits. So they are generally acknowledged to be safe.
But it’s always best to check with your vet before you make any major changes to your cat’s diet.
They will take into account the background fatty acids already present in your cat’s main food, their size, age, and other relevant health factors.
Furthermore, ingesting high quantities of fish oil has been linked to vitamin E deficiency in cats, so your vet will help you monitor and correct against this happening.
Please don’t be tempted to give your cat fish oil supplements intended for humans.
Many human supplements, such as cod liver oil, contain large quantities of vitamin A which your cat may not be able to digest safely.
A product designed for pets, and recommended by your vet, is far safer.
Using Fish Oil To Treat Dry Skin In Cats
Supplementing cats’ diets with fish oil to combat dry and itchy skin conditions like flea allergy dermatits and atopic dermatitis has been a subject of veterinary research since the 1990s.
In 2010 a small study on 14 cats found that a diet supplemented with fish oil can reduce skin inflammatory responses in cats with allergies, especially when combined with flaxseed oil.
However, a study submitted to the Veterinary Record in 1993 suggested that fish oil by itself was not enough to resolve miliary dermatitis (the itchy, scabby rash often suffered by cats with a flea bite allergy).
Although when combined with evening primrose oil, it was.
Since healthy skin supports a healthy coat, many cat owners who give their kitty fish oil also report an improvement in the overall condition of their coat too. However, this is currently only supported anecdotally.
Using Fish Oil To Treat Kidney Disease In Cats
Kidney disease and loss of kidney function is a common problem in older cats. Up to 30% of cats over 15 years old will eventually succumb to it.
Kidney disease is all the more distressing since it is a progressive condition which will ultimately result in total kidney failure.
Following a strict veterinary-prescribed diet has long been a key part of extending the lifespan of a cat with kidney disease.
Indeed, if your cat has kidney disease, you won’t be making any changes to their diet without consulting their vet first!
They probably already know that fish oil for cats with kidney disease can help secure a longer period of healthy kidney function.
In particular, the fatty acid eicosapentaenoic acid (no, I can’t say it either, but try and remember the name for later!) found in fish oils has been shown to significantly improve the prognosis of cats with kidney disease.
Using Fish Oil To Treat Bladder Problems In Cats
Another area researchers have recently found promising results from fish oils is in the toilet department.
In 2017, scientists at Oregon State University discovered that cats taking supplemental fish oil had lower concentrations of calcium in their urine, and lower oxalate crystal formation, which in turn meant fewer urine stones.
This is great news for any cat prone to urine stone formation, which of course includes cats with kidney disease!
Using Fish Oil To Treat Constipation In Cats
What about fish oil for cats with constipation? Because oil lubricates stuff… right?!
And it’s true that when we’re constipated, fatty acids and the bile acids we synthesize to digest them can produce diarrhea.
If you’re lucky that will clear the clear the blockage, but if you’ve ever tried it you’ll know the results can be a little, well… sudden, unpredictable and explosive.
So it’s not a great solution for your cat. Besides the uncontrollable diarrhea, the loose feces can leak past the compacted stool which is causing constipation anyway.
This means your cat has diarrhea, they’re becoming dehydrated, and they are still constipated too.
Which is why you should always visit your vet for a gentler solution to constipation, rather than self administering fish oil!
Fish Oil Dosage For Cats
If you think your cat would benefit from this wonder food, what’s the best way to go about giving it to them? What is the best fish oil dose for cats?
A 1998 review article of studies into the effect of diet on skin diseases in dogs and cats found the that fish oil supplements usually take three to eight weeks to take effect.
They also found that several studies returned disappointing results because the amount of fish oil being administered was too low.
This teaches us two things:
- Firstly, if you decide to purchase this supplement for your cat, look for a liquid fish oil for cats that contains pure, high quality oils.
- Secondly, ask your vet to help you work out the right dosage for your cat!
Getting It Right
So, fish oil really does have the potential to help cats with a lot of health problems, as well as improve their overall condition.
Whenever you’re using elevated doses of fish oil to treat particular problem, you should always do so with your vet’s guidance.
These are the kind of products they might recommend:
Cat Food With Fish Oil
A good place to start is with complete foods that already include an oily fish component.
Purina Fancy Feasts Broths – Seafood Flavors
These pre-prepared wet meals for cats* include several seafood options which contain oily fish such as tuna, mackerel and salmon as their main ingredient.
They also also vitamin E to protect against deficiency.
Happy purchasers say they are well-received by their cat, and the single portion size is ultra-convenient.
Canidae Grain Free Pure Cat Dry Food
If your cat prefers a dry food diet, this special recipe for easy digestion* centers around salmon or trout.
This food gets positive reviews overall, but it definitely seems to be the marmite of the cat food world, with some kitties going crazy for it and others running a mile!
Luckily it comes in several bag sizes so you can find out which side of the fence your cat is on without stockpiling huge quantities!
I and Love and You Naked Essentials Grain Free Dry Cat Food
Another grain free choice for cats with sensitive tummies, this recipe contains salmon and trout as main ingredients*, as well as added fish oil and flax oil for omega-3 and -6 fatty acids.
Liquid Or Chewable Fish Oil Supplements For Cats
Alternatively, you can buy liquid fish oil to add to the meals your cat is already eating.
Most fish oil supplements for cats come in bottles with a pump action dispenser to squirt on to meals.
These are the best we’ve found:
Nordic Naturals Omega 3 Fish Oil Liquid
This fish oil comes from wild anchovy and sardines*.
It contains 31% omega fatty acids, including 17% eicosapentaenoic acid (remember the one which which helped cats with kidney disease?)
The bottle comes with a pipette for accurately measuring your cat’s dosage.
Terramax Pro Omega 3 Premium Liquid Fish Oil
This highly-rated supplement includes fish oils from sardines, herring, anchovy and mackerel*, caught using dolphin-friendly fishing methods.
This fish oil supplement for cats contains 35% omega-3 fatty acids, 18% eicosapentaenoic acid, 7% omega-6 fatty acids, and no preservatives.
The pump action bottle makes accurate dosing a little trickier, but can be less messy, if you know you only need whole “squirts”.
Grizzly Salmon Oil Cat Food Supplement
This pure salmon oil* has amassed legions of loyal fans.
The fatty acid content is fractionally lower than other oils – 29% omega-3, 10% eicosapentaenoic acid and 3% omega-6.
But this simply represents the different amount of fatty acids in salmon compared to other fish.
This oil might be an acceptable choice if your cat doesn’t like the flavor of other fish oils.
Bonnie and Clyde Wild Omega 3 Fish Oil
This well-loved oil is derived from sardines, anchovies and mackerel*.
It also contains added vitamin E, to protect your cat against deficiency.
Makondo Pets Skin and Coat Supplement for Dogs and Cats
If your cat rejects fishy flavors, these chewable bacon-flavored supplements* might be just the trick.
Each tablet contains 250mg of fish oil, as well as rich combo of other vitamins and minerals (including vitamin E)
You vet can help you decide how many your cat should have per day.
Fish Oil Treats For Cats
A fun way to get a bit of extra fish oil into your cat is to find treats containing fish oil, and use them as part of games, or as rewards when you’re teaching good behavior.
They might not be a practical way to administer meaningful quantities of fish oil, but they are a bit of fun nonetheless.
We think these fish oil treats for cats fit the bill perfectly:
Zesty Paws Pure Freeze Dried Salmon Filet Treats
These treats are simply chunks salmon, preserved by freeze-drying*, and with nothing else added.
They’ve got a small but loyal following, and they’ll appeal to you if you like your pet food to be low on ingredients, and recognizable for what it is.
Feline Greenies Smart Bites
These treats position themselves as a treat and multi-vitamin all in one*, but really the total fatty acid content is negligible – less than 1%.
However, they’re a tasty reward if you’re teaching your cat tricks, and offer a little health boost as well.
These also come in chicken flavor*, for the cat who doesn’t like fish:
Fish Oil For Older Cats
We know a few ways fish oil can benefit older cats.
In 2012 researchers in Missouri and Canada found that a diet supplemented with fish oil, antioxidants and B vitamins could protect older cats from brain aging and dementia.
This followed a 1979 study at the University of Michigan which indicated that omega-3 fish oil for cats could protect them from strokes.
Fish Oil For Kittens
Fish oil should be safe for cats of any age, though most benefits will had for older cats or cats who are unwell.
Kittens can have fish oil as a supplement or eat kitten food that includes fish oil.
The main thing for kittens, however, is that they eat a diet that gives them the complete nutrition they need as they grow.
Alternatives
Suppose you’re not completely on board with fish oil supplements?
Or suppose that your cat just doesn’t like the taste? That may seem unlikely, but it could happen!
Here are some other possibilities for increased dietary nutrition.
Fish Oil For Cats
Fish oil as a supplement for cats can be a fantastic boost to their overall nutrition, especially if they are older or unwell.
It can also be used to combat certain skin conditions.
Cats tend to love the taste of fish, so it could be an instant favorite, as well!
But remember to check with your vet for the best fish oil for cats dosage, since it varies from cat to cat.
Have you tried giving your cat fish oil? We’d love to hear about your experiences in the comments below.
Affiliate link disclosure: Links in this article marked with an * are affiliate links, and we may receive a small commission if you purchase these products. However, we selected them for inclusion independently, and all of the views expressed in this article are our own.
References and Further Reading
- Fish and Shellfish, National Health Service
- Plantinga, E, et al, 2003, The influence of dietary fish oil vs. sunflower oil, Journal of Animal Physiology and Animal Nutrition
- Watson, T, 1998, Diet and Skin Disease in Dogs and Cats, The Journal of Nutrition
- Yuanlong, P, et al, 2012, Cognitive enhancement in middle-aged and old cats with dietary supplementation with a nutrient blend containing fish oil, British Journal of Nutrition
- Black, K, et al, 1979, The protective effects of dietary fish oil on focal cerebral infarction, Prostaglandins and Medicine
- Culp, B, et al, 1980, The effect of dietary supplementation of fish oil on experimental myocardial infarction, Prostaglandins
- Hendriks, W, et al, 2002, Vitamin E Requirement of Adult Cats Increases Slightly With High Dietary Intake of Polyunsaturated Fatty Acids, The Journal of Nutrition
- Park, H, et al, 2011, Dietary fish oil and flaxseed oil suppress inflammation and immunity in cats, Veterinary Immunology and Immunopathology
- Harvey, H, 1993, Effect of varying proportions of evening primrose oil and fish oil on cats with crusting dermatosis, Vet Record
- Plantinga, E, et al, 2005, Retrospective study of the survival of cats with acquired chronic renal deficiency offered different commercial diets, Vet Record
- Hall, J, et al, 2017, Increased dietary long-chain polyunsaturated fatty acids alter serum fatty acid concentrations and lower risk of urine stone formation in cats, PLOS One
This article has been extensively revised and updated for 2019.
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Almost a week now that I’m giving my 10 month old cat the smallest dose of Grizzly salmon oil with a dropper. I suspect allergies due to excessive scratching even though her skin shows no signs of infections, dry scales or debris of any kind. My concern is that she gags after giving her the dropper of oil. She will not touch food if I put the oil on it. Should I stop?
Linda, I don’t know if you still have an issue, but I can get my cats to eat almost anything – including fish oil, probiotics, and l-lysine – if I mix it into a tiny bowl of rehydrated Honest Kitchen cat food. They love that food-beg for it, even. Good luck!
My cats don’t like grizzly salmon oil in their wet food, or mixed with their crunchies. Long haired car pulls his fur(not till bald, tho), ends up eating a lot of it coz it sticks in his mouth. Hairballs!! Trying to lubricate his digestive tract. Help!!
Every 2-3 nights I break a fish oil capsule over my 11 year old cats dry food.
I have found that he loves it for one and for another it helps with his bowel movements.
I have been doing this for a couple of years with no known side effects.
My two cats hate it when I break the omega fish oil caps over their food. And, I’ve bought two different kinds. Both are recommended and one was mentioned in the article. But they hate them both. I cant blame them because if I had to break open my own omega supplements and smell them, I probably wouldn’t take mine either. I don’t know what else to do. Help!
I just tried putting a pump full on my cats dry food. She was really hungry but she took one sniff & walked away. Lol. I put some regular food without it in another bowl after & she ate that up.
Exactly what mine did. Anything soft or dry food he walks away