Features September 2012 Issue

The Benefits of Fish Oil to Your Dog's Health

This is one supplement that can benefit all dogs and help with a variety of conditions.

[Updated June 20, 2017]

Fish oil is probably the most important supplement you can add to your dog’s diet, regardless of what type of diet you feed. EPA and DHA, the omega-3 fatty acids in fish oil, provide widespread benefits, but they are fragile and unlikely to survive storage in bags of kibble, or may be rancid even before being added to pet foods. Krill oil and whole fish also provide EPA and DHA that may be better absorbed, providing similar benefits in smaller doses.


Proven benefits from EPA and DHA include:

-Improving the coat and skin.

-Reducing inflammation due to conditions such as arthritis, allergies, and inflammatory bowel disease.

-Regulating the immune system, boosting those that are suppressed and calming overactive immune systems for dogs with allergies or autoimmune diseases.

-Aiding in mental development of fetuses and puppies, and improving cognitive function in older dogs.

-Lowering blood pressure and triglycerides.

-Providing support for dogs with kidney disease, heart disease, and cancer.

-Promoting weight loss in overweight dogs.


Fish oil should be protected from light, heat, and air. Store liquid fish oil in dark bottles in the refrigerator. Purchase amounts that can be used within one or two months to avoid rancidity. If you notice an “off” odor, discard the oil.

Independent agencies have tested many human and pet supplements. None have found mercury, but a few products had unsafe levels of PCBs, provided less EPA or DHA than was shown on the label, or were spoiled. For those concerned about contaminants, look for molecularly distilled products (note the term “pharmaceutical grade” has no legal definition). More concentrated forms, with higher amounts of EPA and DHA per gram, result in lower levels of contaminants.

Liquid fish oil products made for humans often contain flavorings that dogs generally do not like.


Use products made for either humans or dogs. The amount of EPA and DHA in various fish oil preparations varies. Look for concentrated forms when giving high doses so you use smaller amounts of oil.

(If you’re concerned about the possible dangers of fish oil to humans, click here.)

Healthy dogs can be given 100 to 150 mg EPA and DHA per 10 pounds of body weight daily; dogs who have health problems can be given up to 300 mg per 10 pounds of body weight. One ounce of canned fish with bones (sardines, jack mackerel, pink salmon) averages about 300 mg EPA and DHA combined.

The recommended dosage of liquid fish oil products is often too high, adding unnecessary fat and calories to your dog’s diet. High doses of fish oil can interfere with platelets and lead to increased bleeding, and too much can contribute to rather than reduce inflammation.

Cod liver oil is similar to fish oil, but most products also contain high levels of vitamins A and D (molecular distillation removes these vitamins). For those who feed a homemade diet that does not include much fish, give an amount that provides about 100 IUs of vitamin D per 25 pounds of body weight daily. Do not use high doses of cod liver oil. If additional omega-3 fatty acids are desired, add plain fish oil.


There are many different brands of fish oil supplements. Here are a few examples:

-Enzymatic Therapy’s Eskimo-3 

-Mercola Krill Oil

-Neptune Krill Oil (NKO) (available in many brands, including Source Naturals; NOW brand failed two ConsumerLab tests)

-Nordic Naturals, a variety of liquid and softgel products for humans and dogs.

-Sogeval’s Derma-3 Twist Caps, highly concentrated softgels.

Mary Straus is the owner of DogAware.com. Straus and her Norwich Terrier, Ella, live in the San Francisco Bay Area.

Comments (25)

What is dosage of krill oil? My dog is allergic to most fish oils ...


S. Royce

Posted by: AlaskaLabLover | September 24, 2018 1:01 PM    Report this comment

what fish oils do WDJ approve of>??? thank you

Posted by: larryc49 | July 14, 2018 7:46 AM    Report this comment

Great article on the benefits of salmon oil. We tried so many brands and are always switching up the oils to get the most benefits for our dogs. Sometimes its salmon oil, sometimes its coconut oil, sometimes its simply fresh salmon, etc. We buy our oil from a little online store called ecohug, they have tons of supplements , all of which are made in usa which we love.

Posted by: Ecohug | February 8, 2017 12:10 PM    Report this comment

I'm confused... in reference to... if I give sardines packed in water daily, how much sardines should I feed? then Do I still need to give fish oil, if feeding sardines. If so I have a cavalier and a chihuahua, I have no idea on how much to give them... I had considered pink salmon in the can. Is one better than the other sardines or salmon? Can they have the bones in the salmon?

Posted by: Debraroon ... I'm confused.. if I feed sardines packed in water once a day. Or should it be everyday? Should I still give fish oil? If so I have a cavalier and a chichuahu have no idea on the amounts needed for these guys. | January 27, 2017 9:25 PM    Report this comment

Has anyone here heard of Kronch Salmon Oil? I bought some of their salmon oil at a pet show because it's cold-pressed so it's supposed to have a higher nutrient content than the other brands out there. Has anyone dealt with this company before? It's definitely had a big impact on my dog's fur, I was thinking to order more on Amazon

Posted by: AMitchell | July 5, 2016 2:14 PM    Report this comment

Many thanks for sharing these incomparable health benefits of salmon oil, best fish oil supplements for your pet's health. It really helps for all those who wants to give a healthy life to their pets for longer runs. But I'll recommend to shop it from a leading salmon supplier and producers for availing benefits for your pooch. Thanks again Mate :)

Posted by: luisparker | December 10, 2015 12:56 AM    Report this comment

Would anyone know the recommended doseage of fish oil for my 240 lb. English Mastiff. Thanks, yes he's a big boy

Posted by: patvl246 | December 31, 2014 1:32 PM    Report this comment

I do know that omega abb3s in your dog's arsenal to wellness is vital. Did you ever hear this," if the fish doesn't fit in the frying pan, don't eat it", as the mercury levels are too high. Also, dr. Becker for seasonal allergies uses quercetin w/ bromelain, histoplex ab and moducare but she doesn't say how much to give. I have a 2 yr. old golden retriever and in January 2014, she, I feel was overvaccinated and around 1.5 mos later, she developed allergies. Yes, I blame myself for taking the dumb heartless vet's suggestion as I did ask for titering. Now I am going through STRESS as even seeing dermatology specialist and was found to be allergic to dustmites, blackants, ragweeds , bermuda and johnsons grass, dandelions, & about 7 more so she is on this serum made up of all these allergens with a 70/30% rate and I was told to continue my supplements as well. It'll take 3 to 10 mos to see if it works, if not, then I feel inclined to get back at these vets that shorten my best friends' lives and take all my $$$$$.

Posted by: akcBrandy2 | October 23, 2014 1:13 AM    Report this comment

I have two large I year old GSD's and am very careful what I feed them. I am concerned that I do not overdo the Omega 3 that I give them. They each get fed 250g's of dried food twice a day. I do give them sardine/pilchards in oil every day (about 70g's each) mixed in with their dried food for their second meal. In addition I also add a supplement of 50mg's of salmon oil on a weekly basis. So far so good, however I am concerned for their long-term health.

Posted by: albertdog | September 30, 2014 3:34 AM    Report this comment

I have experimented with many oils like Krill & coconut oils and Salmon oil has always been one of my top choices. Its nutrient -rich diet for dogs. Also, I would like to recommend Norway based company Biomega AS, www.biomega.no to pet food producers for fresh salmon oil and salmon meal.

Posted by: luisparker | September 11, 2014 6:29 AM    Report this comment

There have been studies done to show that the Omega 3 in real fish is much more bioavailable to the dog than the Omega 3 in capsules. Studies have shown that a far greater amount of capsules are required to equal the bioavailability of EPA/DHA in real fish.....in other words, the nutrients in the real fish are going to be recognized by your dogs body and utilized more successfully than the capsules.

It is far more beneficial to feed your dog real fish over using capsules. There is so much more in the way of nutrition in real fish, in comparison to feeding a fish oil capsule. Real fish has many valuable nutrients to nourish your dog and keep him in optimum health.

Posted by: DuryLane | March 17, 2014 10:27 AM    Report this comment

I was under the impression fish oil will not only help with inflammation caused by allergies, but the allergies themselves. Is this correct?

Posted by: Annie Klacks | January 22, 2014 1:50 PM    Report this comment

You state that high doses of fish oil can actually contribute to, rather than reduce inflammation. I would be interested to know the source of this information, since I've not heard that before?

Posted by: SueS | November 10, 2013 10:16 AM    Report this comment

I give my dog a large sardine (packed in water) mixed in with her kibble once, sometimes twice a day. They are pretty high in fish oils, and it makes her kibble more appealing, also they are inexpensive.

Posted by: JohnHoz | November 9, 2013 9:52 PM    Report this comment

i have a small (15 lbs) dog and the bottle is rather large. the nordic naturals rep said i could store the bottle in the freezer; i keep a small amount in fridge in a dropper bottle and replenish as needed. keeps a very long time in the freezer and the bottle won't break.

Posted by: chris p | November 9, 2013 2:00 PM    Report this comment

I agree with many of the commenters that it is better to use "the real food". I also disagree with the subtitle and caution Ms Strauss not to make such sweeping statements about being good for all dogs. Many dogs, mine included, do not tolerate fish oil supplements.

Posted by: lsabatini | November 9, 2013 12:46 PM    Report this comment

I would like to know how to find the product test comparisons for myself, since I retail pet supplements and want to evaluate claims. Is there a site where this information is compiled or searchable?

Posted by: LaurieR | November 9, 2013 11:46 AM    Report this comment

Unfortunately we have no idea what happens to a product once it is shipped from the supplier. What may have started out as a very good quality product may be something quite other than that by the time the consumer buys it. Most are transported long distances by rail or truck with no consideration about the temperature. I doubt that many are shipped in refrigerated containers. The better solution might be to feed the dog the real deal. Add some kind of safely harvested oily fish to his regular food each day. My experience is that the cost is not really greater than some of the supplements out there. My aussie's annual vet visit two weeks ago resulted in quite an exclamation regarding the great quality of his coat. As we all know coat condition provides a strong indication of over all health. We have to assume it is as a result of the salmon added to his food every day.

Posted by: Barbara W | November 9, 2013 10:27 AM    Report this comment

I feed my dog Blue Buffalo Salmon and Potato with Salmon as the first ingredient. Do I still need to give him fish oil even though he gets all the fish?????


Posted by: danoon58 | August 16, 2013 2:50 PM    Report this comment

Pet-grade fish oil supplements can be rife with toxins, I would never feed those to my dog. I agree either a human brand like nordic naturals or the pet brand Celavin from nusentia... both are guaranteed pure and free of pcbs and other toxins that usually accompany fish oil supplements.

Posted by: firstlady | May 29, 2013 6:57 PM    Report this comment

I love nordic naturals! However, I don't bother buying the pet products, too pricey. I just give the pooch one of my pills everyday while I take mine. He likes it. I just wonder if he's getting enough...or too much. But seeing the numbers up there: 300 mg for dogs with health problems..And he's 55 lbs. I think maybe he could do for taking two.

Posted by: Andrea J | May 23, 2013 10:10 PM    Report this comment

I take fish oil every day. Can I give the same capsules to my dog?

Posted by: Carol Z | September 11, 2012 12:16 PM    Report this comment

All my dogs get salmon oil on a daily basis and they have great coats and great energy levels. Can highly recommend it.

Posted by: WTDT | August 25, 2012 3:02 PM    Report this comment

Pls friends am just a begin with six different breeds.i need informations on how to grow them

Posted by: Unknown | August 25, 2012 2:30 PM    Report this comment

Thanks for the article. My favorite line is "One ounce of canned fish with bones (sardines, jack mackerel, pink salmon) averages about 300 mg EPA and DHA combined." as I prefer to use "real" food instead of supplements whenever possible. I am working towards fully home prepared meals and these articles really help.

Posted by: Remysmom | August 20, 2012 12:38 PM    Report this comment

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