Answers: What Dry Food Does to Your Cat's Teeth

Updated: Saturday, May 04, 2019 09:05 PM

Published: Saturday, April 04, 2015 12:33 PM

Written by Guillermo Díaz. MV

For years, I've been feeding my cat the commercial dry diet my vet recommended. In the last visit to the clinic, however, he told me she was developing tartar on her teeth, her gums were inflamed and she needed to go under anesthesia for a dental cleaning. How can this be? I've followed his instructions verbatim. I feel like there's something missing here.

The fact that we humans have taken the cat with us to live under a roof doesn't change their marvelous biology and evolution as true, obligate carnivores. In fact, what we have taken home is a miniature tiger, lion or leopard. You name it. Domestic cats have kept the carnivore instincts they evolved with intact as they moved in with humans. We are the ones who are making a mistake when we stray from what evolution and nature has provided the cat.

During my veterinary internship, one of the rotations I was required to do was at the zoo working with big cats such as pumas, lions and tigers of different ages. During that time, I never encountered a single big cat with tartar built up on its teeth. This was in sharp contrast to the great number of domestic cats I saw who did. The questions popped up instantly in my mind: How have these big felines managed to keep their teeth so neat? Why do we fail to get the same results with our cats at home?

The answer is simple: the difference is in the food.

Big cats and domestic cats share the same body form and the same dental structure and shape. They all have big canines designed to rip and tear a carcass, and upper and lower molars and premolars that close perfectly like scissor blades, designed to shatter bones and slice flesh. When eating raw meat and bones, the act itself of chewing and gnawing serves as a polisher of the surface of the teeth, preventing the buildup of plaque and tartar. This is the equivalent of humans brushing and flossing our teeth. This happens every day with each meal, which means felines consuming raw meaty bones get a daily dental cleaning and brushing.

Unfortunately, the opposite occurs when we feed our cats commercial dry food. The shape of the kibble is generally small in size which makes it difficult for a cat to chew, so they generally swallow the whole pellet as presented. This has zero polishing effect on the surface of the teeth. Moreover, when in contact with the saliva, the high content of carbohydrates, or polysaccharides, in the pellet is released and adheres to the surface of the teeth, causing the first stage in the formation of tartar and periodontal disease, dental plaque.¹

Once this plaque has set in, stage two begins, the buildup of tartar, also called calculus. From here onwards, we can find different levels of periodontal disease. This gradation exceeds the aim of this article, but the important thing for owners to remember is that the calculus on the tooth carries millions of bacteria which reproduce at a high rate. The byproduct of this is stinky breath, ingestion of toxins, drooling, sore and bleeding gums, loose teeth, tooth loss and destruction of the jaw bone. The damage can reach different and vital organs such as kidneys, lungs, heart and liver as the bacteria spreads beyond the mouth. In the worst case, this can be life threatening. Your cat's oral health needs to be taken very seriously.

A small test with dogs conducted in Australia showed how quickly dry foods can affect the teeth.² Four dogs, who were all raw meaty bone eaters, were fed only dry kibble for 17 days. At the end of the experiment, the dogs had developed stinky breath and yellow teeth. Some of them lost weight. All of them had behavioral changes, itchy skin, bad breath and intestinal disorders including larger volume of stools, offensive smell and runniness. Even though this test was with dogs, not cats, the effect is the same for carnivores that evolved to eat a prey-based diet.

So the lesson is clear, give your cat what Mother Nature intended her to eat. A raw cat food diet should include meat chunks and raw meaty bones to provide the scraping/cleaning action and encourage your cat to gnaw and chew using the scissor-like side teeth. Avoid carbohydrate-based foods that can set your cat up for dental problems. While every cat is different and some are genetically more predisposed to dental problems, feeding the right kind of food can give your cat the best possible chance for a healthy mouth.

Note: Feline Nutrition provides feline health and nutrition information as a public service. Diagnosis and treatment of specific conditions should always be in consultation with your own veterinarian. Feline Nutrition disclaims all warranties and liability related to the veterinary advice and information provided on this site.

Dr. Guillermo Díaz and family, including their four dogs (Leroy, Xica, Moza and Pepa) and six cats (Michalina, Tigger, Vladimir, Yellow, Mongo and Chirusa) moved to Buenos Aires, Argentina in July of 2017, where he expects to continue supporting different animal rescue groups, spread the benefits of raw food for cats and dogs and write articles about nutrition.

1. C Zambori, E Tirziu, I Nichita, C Cumpanasoiu, RV Gros, M Seres, B Mladin and D Mot, "Biofilm Implication in Oral Diseases of Dogs and Cats," Scientific Papers: Animal Science and Biotechnologies45, no. 2, 2012.

2. Dr Tom Lonsdale, Science Death Experiment, 2015.