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Featuring Demian Dressler, DVM and Sue Ettinger, DVM, Dip. ACVIM (Oncology), authors of The Dog Cancer Survival Guide

Help overcome dog food dangers: which oils for cancer??

Updated: December 12th, 2018

Rochelle Lesser, who created and manages a great site for Golden Retrievers (and dogs in general), asked about krill oil on a recent post.  Here’s the skinny on why I like its cancer-fighting benefits (krill are those tiny shrimp that whales eat).

First,  krill oil helps offset the omega 6 fatty acid excess I wrote about in the post before last, by supplying needed omega 3 fatty acids.  This helps block the inflammation and suppression of cancer-fighting white blood cells caused by excess omega 6’s. Too much omega 6 fatty acids are found in many commercial dog foods in corn products, vegetable oils, meat fats and more.

Other good sources of omega 3’s are fish oils of various kinds, with Chinook salmon, mackerel, menhaden, and sardine also being up there. So giving these oils stimulates cancer-fighting white blood cells, and decreases inflammation (inflammation is a central part of cancer development). Omega 3’s can also help fight cancer weight loss (cachexia), slow tumor growth, and lessen spread in many cases. So krill and fish oil both are good in these regards.

However, with our understanding of the link between depression in people and cancer, it becomes obvious that this is a massively overlooked problem in dogs.  To my knowledge, this is an area that has not been addressed in any formal way and will be viewed at as “out there” by many conventional vets.  I firmly believe that this line of thought is on the leading edge of a whole new way of looking at dog cancer.

With this in mind, back to krill oil.  Krill do not accumulate heavy metals, so this is not a concern in their oil.  Additionally, they are rich in EPA, the omega 3 fatty acid that has been shown to fight depression and inflammation.  Krill has more EPA than fish oil.  Here is more info. Since depression in people increases cancer, addressing this in dogs is very logical. On top of this, Krill has the capacity to actually restore the size of brain parts that have literally shrunk in depression. This may be due to its phospholipid content, of which krill has more than fish oil. Amazing!

Yes, krill oil costs more than fish oil.  However, you can get away with less, probably about 1/4 less than fish oil. I would recommend about 4-6 of the 500 mg krill oil capsules daily for a 40 lb dog, costing roughly $3 daily.  Not cheap, but good!

To be safe, stop fish oil or krill oil about 10 days before your dog has any surgery.

Thanks to Rochelle of The Land of Pure Gold for the great question!


Best to all,

Dr Dressler


Leave a Comment

  1. brittandpuggle on March 4, 2014 at 4:04 pm

    for a dog with MCT is fish oil ok? I saw that Dr. Dressler suggest no fish for MCT cancer. Does this include oils?

    • Susan Kazara Harper on March 5, 2014 at 8:34 am

      Hey Britt, We’re preparing the full blog on MCT diet as I write, but as to the question on oil:
      Although the processing of the oil alters the original material, fish itself is on the ‘no’ list. However, Dr. Dressler recommends krill oil over other fish oil supplements for many reasons which he explains in the book. We have found that Mercola Krill Oil and Jarrow Formula Neptune Krill Oil both contain histamine “below detectable levels” which is about as good as it can get. So the benefits of giving krill oil outweigh the infinitesimal amount of histamine which may be present. Both of these oils are available through the Dog Cancer Shop. I hope this helps.

  2. Greyhoundadoptee on October 21, 2013 at 5:28 pm

    I have myself switched from fish oil to red krill and find it much better to relieve my achy joints. I have a greyhound, and a greyhound mix, both have occasional stiffness, and I was wondering about krill for them also. Who do I believe?

    • Abby's Mom on October 26, 2013 at 1:21 pm

      My Abby at age 13 developed osteosarcoma in her thoractic cavity–not in her skeletal system. Never had any symptoms until I found a lump towards the back of her stomach. WSU Vet Hospital has only seen one other case. I always had Abby on vet recommended (Arctic) fish oils. My question is: could this have helped to somehow have thwarted/re-directed the disease and perhaps extended her life?

  3. Leanne on December 30, 2012 at 11:58 am

    I really need some advice. My dog was diagnosed with Multiple Myeloma August 18th 2012. She had a tumor that seemed to appear overnight. It was on her underbelly left side by her leg.

    My dogs name is Roxy. A Yorkshire that turned 11 in June 2012. She has never had any health issues.

    I found your website as I was trying to learn about what to do. My vet is not a specialist but sought out advice from a cancer vet. She had surgery and the lump removed but vet said it crumbled and he could not get it all… I am currently giving her Chemo (mylanthen)every day and Steroid every other day. Chemo is .25 liquid form. She tolerated and her blood work was pretty steady for the last few months. I have been taking her every couple weeks to check blood work.

    Latest Stats:
    Total Protein : High 8.0
    Total Globulin High 4.6
    A/G ratio LOW 4.6
    BUN High : = 60mg/dl
    Bun Creatinine ratio high 75

    I downloaded your diet I took her off dog food completely and have been trying to make chicken, turkey and hamburger for most part. I don’t think I have the diet right its a struggle. She wont eat the rice and now wont eat cottage cheese and cottage cheese does have sugar in it and salt. I’m not sure about that. I bought the Apocaps a few weeks ago and have been giving one a day. ( they are very large capsules.) and add 1/2 capsule of fish oil to her food twice a day. They are 1000 mg each. The diet I broil, boil and or cook in pan. Usually chicken breast with parsley, garlic, ginger and I found a salt free spices that have onion, parsley, basil oregano, thyme, red pepper, garlic, lemon peel and paprika. Is this OK? I sprink on meat for flavor. I just bought a powder form of cranberries to sprinkle in her food but I’m not sure that’s ok either so I have not given to her yet.

    I try to get cauliflower mushed up in her food and sometimes she eats it. But I’m afraid she’s not getting the complete diet. I have been giving her treats that are freeze dried – chicken and salmon treats. That’s the only ingredient in them.

    My vet told me to take her off chemo for a week and since her blood work was not good. I could not get back for blood work for 10 days so I asked him if ok to give every other day ..he agreed. I just took her Saturday and will get results Monday.

    Do you have any suggestions with her diet or recommendations on what else I can do.

    Shes been ok so far.. SLower and trouble now getting upstairs but she has not vomited or lost any weight .. Shes always been around 10 pounds and shes 9.8 now. Shes overweight she should be 7 or 8 ANY advice would greatly appreciated because I don’t know what to do anymore.

    • Dr. Demian Dressler on January 2, 2013 at 12:17 pm

      Dear Leanne,
      I am having trouble getting to the root of your question so i will do my best. It seems you are concerned that she is not getting a balanced diet because she won’t eat certain ingredients or is finicky in general. The problem is less likely the diet and more likely that either the chemo or her cancer is making her lose her appetite. First, when you have decreased appetite, you need to talk to your vet about what to do to get the appetite up. This may mean switching the present treatment plan if it is making her sick. Appetite stimulant options include mirtazapine (one my my favorites), ondansetron, and also famotidine, omeprazole, sucralfate and other meds may help. Additionally you can give your dog a little ginger and slippery elm. Discuss these with your vet please.
      Dr D

  4. JLWW on January 3, 2012 at 8:44 am

    Dr Dressler, thanks for all of your great information above. Our dog is a cancer survivor and we do give him fish oil to keep his immune system up. However, the fish oil makes him extremely gassy and is not pleasant to live with. We were told by one vet who was giving out free advice at a dog food store that higher EPA and lower DHA would help the gassiness issue. He also receives immune system building tablets which work great and eats Taste OF the Wild Food which he has done well on now for a few years. Rather than give him more supplements to offset the gassiness, I am wondering if there is a different fish oil we can give him , or a different ratio of EPA to DHA we can give him that will slow the gassiness down. THe ratio he is currently taking is 1000 mg 2 x per day and he weighs 26 pounds. If we give him less, he gets hot spots and licks himself excessively. This has stopped it completely, but man does he stink. No diarrhea though. Any suggestions? Thank you!

    • Dr. Demian Dressler on January 4, 2012 at 4:56 pm

      Dear JLWW,
      beta glucans are more effective (found in apocaps, along with a host of other beneficial constituents).
      In addition, try Krill oil, might help instead of fish oil. This is discussed in the Guide.
      Remember to make all health steps under veterinary supervision.
      Dr. D

  5. Tammy Johnson Mayer on June 18, 2011 at 3:51 am

    Hello, May I ask a question about some Krill OIl (Organika – bought in Canada) that I bought for our dog yesterday? She’s about a 13 1/2 lb. bichon and is in remission from a sarcoma.

    It says on the label that it contains no artificial sweeteners, but it then lists gelatin, natural vanilla flavour, glycerin and sorbitol as non-medicinal ingredients. My concern is the sorbitol. They are 500 mg capsules. I’m aware that sorbitol is safe in small amounts, but can cause intestinal tract upset potentially. The reports about toxicity are confusing. Should I try to take this stuff back?

    Thank you,

  6. Michelle on March 23, 2011 at 10:16 am

    Hello, I currently am using Carlson Super Omega 3 fish oils and I noticed they now have the “ELITE” super omega 3 oils which has a little higher concentration of omega 3’s but they contain lemon flavor. Is it safe to give my dog Lemon Flavored fish oils or is it better to just stick with the non flavored kind. Also I have a 90lb Rottweiler and my vet suggested for her to take 1000mgs daily. I was wondering if this is enough for her size or if I should be giving a little more. My last Rottweiler was on 2000mgs daily but she was also battling cancer and proudly I can say she was a cancer survivor for 7 years and lived to be 10 years old. But I was wondering if you should only be giving 2000mgs daily to a dog that has health issues like she did. But for a healthy 90lb dog is 1000mgs daily enough.Thanks so much!

    • DemianDressler on April 6, 2011 at 8:58 pm

      Dear Michelle,
      I would lean towards omega 3 without the lemon flavor. This dose of quite low for a dog that size. However, I would hesitate to go against your vet’s recommendation. Maybe you could ask to see whether a higher dose could be considered?
      DR D

  7. Wendy on January 12, 2011 at 11:25 am

    I work in the natural health industry and have referred many people who have pets with cancer to a product called flax hull lignans. My own little Chihuahua had two tumors that dissappeared completely after getting the flax hull lignans in his diet. The lignans have flax oil in them but that’s not all. They are proven to kill cancer cells. There is a doctor with his PHD in immunology from Berkley who says that the lignans cause cancer cells to kill themselves. There is a lot of research out there…some organizations like AIDS Research & Assistance Institute have done lots of studies on it. Many pet owners who have pets with Cushings Disease also are using the lignans with success.

  8. Salmon Oil - Boxer Forum : Boxer Breed Dog Forums on September 24, 2010 at 2:34 am

    […] so young), so I'm linking an article from dogcancerblog on krill's benefits for fighting cancer… Help overcome dog food dangers: Krill Oil versus Fish Oil Krill does not come in liquid form, only softgels. You poke it with a pin and squeeze over food. […]

  9. Cliff on June 24, 2010 at 5:12 am

    I see a lot of articles about using fish oil, krill oil and other sources of Omega 3’s and the necessity to offset excess Omega 6 when fighting cancer.

    We do not feed our dog with cancer any grains. And have taken him off of any commercial dog food due to the excess amount of carbohydrates in the commercial foods.
    Using human grade meats: chicken, lean beef, salmon, sardines.
    Also giving supplements with vitamin E, fish oil and flax hull lignans.

    The question is : The articles all assume that the dog is getting enough Omega 6’s from the commercial food that contains grain or corn. But that assumption is not correct in all dogs as many dog owners do not feed a commercial food.
    With your articles recommending the reduction of Omega 6’s, when treating a dog with cancer (histiocytic sarcoma) is it preferable to eliminate all the Omega 6 as possible from the diet? I do understand that their are Omega 6’s in the meat of the chicken and beef. Are Omega 6’s essential in a diet for dogs?

  10. Mary Parker on May 23, 2010 at 10:36 pm

    thank you for all of the above suggestions and recommendations. My dog has been diagnosed with Cushings syndrome – I am heart broken and spend hours and hours doing research on how to help her feel better and live a longer life. thank you for all your blogs.

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