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

Preservatives and Cancer: Believe the Hype?

Updated: August 8th, 2019

Do preservatives in dog food cause cancer? Good question.

Dog lovers seem to divide themselves into two camps.  The first camp says, “Well, whatever.  Everything causes cancer.  I’m not going to worry about it.”

Camp two says, “I only feed my dog all-natural food or home-made organic meals. We prefer alkaline water and do not feed our dog poison.”

Interesting. Both sides have merit.  Camp one’s viewpoint infers that we should perhaps have a critical eye before believing everything and becoming paranoid.

On the other hand, camp two’s perspective reminds us to try to widen back and perceive our carcinogen exposure.

(If you are interested in learning more about quite a number of carcinogens, check out the Dog Cancer Survival Guide.)

So, what about preservatives?

Two biggies that deserves mention are sodium nitrate and nitrite.  Sodium nitrite is the pink stuff that one finds in our pink deli meats, ham, hot dogs and so on. It is also used in many different doggy treats and some foods. Sodium nitrate is formed when sodium nitrite reacts with oxygen in the air.

True, they are not carcinogenic.  Sitting outside your dog’s body, there is no problem.

However, there is a problem after they are eaten.

These compounds are converted to other substances in the intestine.  Our dogs have a normal population of bacteria that live in their intestines, just like we do.

These bacteria are quite helpful.  The crowd out disease-causing agents, they help break down certain dietary components, they help with vitamin production and they produce healthy fatty acids, just to name a few benefits.

However, there is a derangement in the normally healthy pathways in the bacteria when you feed your dog nitrates and nitrites.

The bacteria convert these preservatives into N-nitroso compounds.  Unlike sodium nitrate and nitrite, the N-nitroso compounds are quite carcinogenic.

It is exposure to carcinogens like these that produces one of the “hits” to your dog’s DNA.  After enough of the right “hits”, in the right individual with the right combinations and adequate time, cancer develops.

Take home message? Avoid these preservatives.

Best to all,

Dr D

Leave a Comment

  1. LC on September 3, 2009 at 8:24 am

    That’s really interesting. We think about that stuff all the time in regard to ourselves and what we eat, but no one ever really thinks about what we feed our dogs and how that can have the same effect on them. What are some other options for a healthy dog diet if you don’t want to go whole hog on the organic diet?

  2. Beth on July 29, 2009 at 5:59 am

    I was wondering if insulinoma is addressed in the Dog Cancer Survival Guide?

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