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

Calcium in Dog Cancer

Updated: December 17th, 2019

Calcium levels in your dog’s body can be  a tricky business.

Like any medical care step, there are different sides of the coin that need to be looked at for your dog with cancer.  First, many dog lovers are feeding their dogs home made diets.  Since these dogs are not eating pieces of a carcass skeleton, they will need to have calcium added to meet their basic needs.

The body uses calcium to maintain the bones, for muscle use, for the heart to pump, for neurotransmitters and more. The daily amount of calcium for an adult dog is 119 mg per kilo of body weight of calcium.

In humans, it has been shown that diets low in calcium increased the risk of cancer of the colon and rectum.

The problem though is that dogs with cancer may have high blood calcium already from their cancer.  Some cancers secrete a substance (PTHrp) that causes the kidneys and bone to act together to raise the blood calcium.  Anal sac apocrine adenocarcinomas do this commonly.

If the blood calcium level is too high, the kidneys can start to mineralize. This hurts kidney function and can cause kidney disease.  High calcium can also cause urinary stones (calcium oxalate).  And moving cells, in particular moving cancer cells, require calcium to travel (if you would like more information on how cancer works, read the Guide).

So we have a delicate balancing act with calcium.

What about calcium sources?  Years ago, I wrote that oyster shell calcium and bone meal were  good sources, but later found that some of these supplements contained lead.  So I eliminated this recommendation and instead focused on chicken necks and/or calcium citrate.

Calcium citrate does not create lead accumulation in the body.  It is also gets into the bloodstream well after taking it in food, where other forms had lower absorption.

Supplementing dogs on commercial foods that are balanced and complete do not need additional calcium supplements.  However, if your dog is on a home made food, you will need to supplement with calcium.

For more information on diet and how to give necessary calcium to your dog, there is a free download on the top of this blog page.  There is more information in the best diet to feed your dog with cancer in the Guide.


Dr D



Leave a Comment

  1. Diane on October 9, 2021 at 4:15 am

    I am trying to find the amount of calcium citrate to put in Barley’s food. I can’t find citracal max without extra vitamin d.

    • Molly Jacobson on October 11, 2021 at 10:05 am

      I don’t believe there is a version of Citrcal Max without vitamin D 🙂 … that’s the “max” part. Use as indicated in the book if this is how you are giving calcium!

  2. Deb on September 24, 2018 at 8:42 pm

    Also wondering about use of eggshells for calcium. My cancer dog has one jaw and no teeth.

  3. Cassandra on May 23, 2013 at 4:08 pm

    What is the mg/kg of calcium citrate recommended for small dogs?

  4. Heather C on May 9, 2013 at 7:53 am

    I also have the same question as Anita. Would you recommend eggshell powder as a good source? I’ve been using it for a little while but if it isn’t an appropriate source I’ll gladly change to something else.

    Additionally, what are your thoughts on PetTabs Calcium formula (daily vitamin supplement).

    My Bear had surgery yesterday.. still waiting on the pathology but I went ahead and ordered your book anyway. Hoping for a holistic way to treat whatever it is he has. I just can’t imagine putting him through chemo and radiation.

    Thanks, Heather

  5. Sandra Dighton on July 30, 2012 at 7:36 am

    I have a friend whose cat has lymphosarcoma. Are there any books out there for her like yours?

  6. Laureli on June 6, 2012 at 10:19 pm

    Are you saying supplemental calcium is also appropriate for the raw diet when we add bones to every meal?

    Lastly, really, you are going to let that Tums comment go unaddressed? That made my head spin. Stop the Tums madness! It’s useless for pets and humans. Find a viable, absorbable source, like Dr. D’s suggestions, and a holistic vet who will test the dog’s levels (ex. blood test, hair analysis) and provide a balanced treatment plan. All the nutrients work together, singling one out could be a mistake for the synergy of the body.

  7. Deb Graf on May 29, 2012 at 2:08 pm

    Question- I am feeding my dog (72lb mix-being treated for anal sac cancer) a home made diet plus about 1/4 to 1/2 cup dry Blue Wilderness each meal. She had a high calcium prior to surgery and after surgery it dropped quickly and was advised to supplement with Tums until blood work stabilized-which it has. Do you think additional calcium is necessary in this case? Thanks-

    • Dr. Demian Dressler on May 30, 2012 at 4:00 pm

      Dear Deb,
      I am sorry but you will need to check with your veterinarian on the calcium recommendations for your dog as this requires individual, fine tuning-
      Dr D

  8. Anita Chaplin on May 29, 2012 at 2:01 pm

    I read the free version about cancer, and this article also about calcium. What is your take on egg shell powder calcium? I’ve been using it for my dogs for some time (they do not have cancer), but it is an excellent source of calcium. I buy organic eggs. I rinse the eggs shells after I have used the egg, allow to dry for at least 24 hours, then run through the coffee grinder until it is a powder, and sprinkle it on my dog’s food twice a day. People can use it too!


  9. Roxanne on May 29, 2012 at 8:35 am

    Hi Dr. D,
    Regarding the issue of calcium, I noticed you didn’t mention dehydrated seaweed as a source. This is what our holistic vet (we have two vets) recommended for us when we started making our pup’s food from scratch. This would seem to bypass some of the other concerns, since it’s just a food source. ??
    Thanks for all you do. Though it looks as if we are finally losing our battle with mast cell cancer in our little Callie, (you may recall the letter and picture we left at your door 2 years ago when we were visiting Maui) she has had more years of thriving than she ever would have, thanks to your help and your assistance in making me a much more informed advocate for her.

    • Dr. Demian Dressler on May 30, 2012 at 4:04 pm

      Dear Roxanne,
      Thanks for your commments! There is some evidence that seaweed based calcium may enhance absorption…so yes!
      Dr D

Scroll To Top