Fish Oil For Cats: Everything You Need to Know

You may be taking fish oil for all the amazing health benefits, including a lowered risk of heart attack. But what about your furry friend? Is there a benefit to fish oil for cats, too? The answer is yes. Fish oil is a wonderful supplement that can improve your cat’s health and wellness. Surely you have a lot of questions, so here is everything you need to know about fish oil for cats.

gray tabby cat

What is Fish Oil?

Fish oil, be it for humans, dogs, cats, or even horses, is a supplement created from coldwater fish that are rich in omega-3 fatty acids, like salmon, pollock, trout, and tuna. The two omega-3 fatty acids present in fish oil is eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These fatty acids are essential, meaning that cats cannot produce them on their own and must ingest them through other food sources.

For example, kittens receive DHA for brain growth and development from their mother’s milk.

Is Fish Oil Good For Cats?

Yes, fish oil is a fantastic supplement for cats for a couple of reasons. First, the fatty acids help promote healthy fur and skin, which is necessary for optimal feline health. Secondly, fish oil boosts the immune system, thereby warding off common illnesses.

Veterinarians recommend giving fish oil to cats for other reasons as well. This is because there are many benefits and uses to a high grade fish oil.

Fish Oil For Cats: Benefits

Here are the main benefits of fish oil for cats:

Brain Development and Cognitive Function

The fatty acids in fish oil are known for enhancing brain development and functioning in both kittens and adult cats. In older felines, supplementing with DHA and EPA can slow the effects of aging on the brain, delaying cognitive dysfunction and dementia.

Anti-Inflammatory

One of the main reasons people pick up fish oil supplements is the anti-inflammatory elements. EPA and DHA, the two essential fatty acids, work to reduce inflammation. In turn, the progression of heart disease is slowed, and arthritis is less painful. If your cat has inflammatory skin conditions or skin allergies, fish oil reduces the itchiness.

Decreased Tumor Growth

If your cat has cancer or a tumor, the veterinarian might recommend a fish oil supplement. Why? Because fish oil makes cancer cells differentiate or turn into other forms of cells. When this happens, the cancer cells can no longer divide correctly and start to naturally die off. In other words, tumor growth slows or stops altogether.

Other Health Benefits

The fatty acids contained in fish oil supplements help with joint, heart, and eye health. You can also use fish oil for cats with irregular heart rhythms or seizures (to reduce the frequency).

Will Fish Oil For Cats Cause Side Effects?

Although fish oil supplements are not toxic and cannot be overdosed, they may cause side effects. The most common is fish breath—which anyone who takes fish oil will understand. Other side effects include oily or flaky skin and gastrointestinal issues.

If you have been giving your cat fish oil and note these symptoms, be sure to speak with a veterinarian.

Can I Give My Cat Human Fish Oil?

You might think to save some time and money by giving your cat a taste of the fish oil supplements you take. Think again!

Human fish oil supplements and cat fish oil supplements are not the same. Please be sure to use fish oil products that have been formulated and tested for cats.

In the US, there are state and federal regulations in place for how much fish oil should be in a supplement. Secondly, many human-grade fish oils contain rosemary as a preservative. Rosemary is not safe for cats and should not be consumed.

Furthermore, many fish oils produced for humans contain other vitamins, such as vitamin A and D. Should a cat take a human-sized fish oil supplement, they may consume a toxic amount of vitamins. This is also why you should not give your four-legged companion cod liver oil.

In short, only buy fish oil that has been formulated specifically for cats. The fish oil should be distilled, reviewed for cat consumption, and follow the standards for pet supplementation from AAFCO, CVM, and USDA.

How Many Mg of Fish Oil Should I Give My Cat?

Generally, a 10 pound cat needs about 200 mg of DHA per day. This means around 25-30 mg/kg of body weight of DHA and 40 mg/kg of EPA daily. Before starting your cat on fish oil supplementation, be sure to consult with your vet. Also, check their food. Many cat food companies have started adding fish oil to food as a way to boost the amount of DHA and EPA.


For instance, if you pour ½ cup of dry food for your cat to eat, they will be receiving around 200 mg of DHA. This means you would not have to supplement. Keep in mind that too much fish oil could cause gastrointestinal discomfort, especially for cats who are smaller in size.

What Is The Best Way to Give a Cat Fish Oil?

There are many fish oil supplements made for cats. Most are oils, not capsules or pills, that can be measured out and poured directly onto food. As long as your cat is about 15 pounds or less, you can mix in ½ teaspoon of fish oil with either wet or dry food. After three weeks, lower the dose to around ¼ teaspoon, once a day.

Larger cats will require a little more fish oil—around 1 teaspoon per day. As their condition improves, maintain the benefits with a ½ teaspoon.

Here Fishy, Fishy

Hopefully, you now know a little more about fish oil for cats, such as the dosage, benefits, side effects, and more. Fish oil is a great supplement for cats that may not be getting enough fatty acids or that have medical conditions like cancer. By giving your friend some fish oil, they will live a longer, happier life for sure!

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