Cat Care For Veterinarians

Myths Debunked #1: Raw Foods & Grain Free Diets

September 28, 2018

Hey Readers!

This is the first in a series of posts where I will debunk common myths about cat care. The first myth I want to tackle is that raw food or grain free food is better than commercial cooked pet food or prescription based food.

First of all, let me say that nothing could be farther from the truth.

So, What Do We Feed Our Pets?

This topic is a controversial one because we get very defensive about what we feed our pets. Somehow, what we feed our kitties becomes synonymous with how good of a cat owner we think we are and how much we love them. We also tend to have the notion that the more expensive the cat food is, the higher quality it is—that the two are directly associated. When I ask owners what they feed their pets, I often get a version of: “I don’t know, but it’s the ‘Gucci’ of pet food.” or “I’m not sure, but I know it’s very high quality because it’s expensive.” Let me just say that price and quality are not necessarily associated.

I’m sure all of us would agree that we try to feed our pets the best food out there.  So, what is the best food? I have two main criteria: The best food is the one that your cat will actually eat that won’t cause vomiting, diarrhea or harm. The next goal with cat food is to find one that will promote long-term health. The latter criteria is the part where we often run into problems.


Marketing plays such a huge role in the trends around us. Who determines what’s “in” in fashion? The fashion industry! They set the trends so they can sell us stuff. It’s a group of people who collectively come together and say: “Weird tiny sunglasses are in” and then before you know it, celebrities are wearing it. Similarly, who determines what’s “in” in pet food? The pet food industry! Do you see a pattern? Marketing is insidious and it permeates the air around us. 

I get it—I’m not immune to trends.  We as consumers and pet owners are constantly trying to find more “natural” foods to remedy ailments, or we cling to the belief that these trends actually can be beneficial. And sometimes, anecdotally they can, but they must also be taken for what they are—marketing tools with no firm scientific basis.

Raw Foods

Raw food diets and grain free diets have been at the forefront of these recent trends. Unfortunately, there is limited data on the efficacy of raw food diets. I can’t argue with owners who swear by these raw food diets and claim that it has helped with their pet’s allergies, intestinal disease, skin condition and etc.  Anecdotal claims only go so far and if owners are convinced that the food has been the sole cause for their cat’s well being, who am I to argue with them? Could it be a placebo effect or something else that the owner was doing that they’re attributing to the diet? Sure. Could it be true health benefit? Sure. But you should always have a reason as to why you’re feeding a raw food diet other than because it’s what is being sold to you by pet food stores because guess what? They are trying to sell you something that the vendor is trying to sell them.

What I do know is that raw foods are not fully cooked to kill all the microorganisms that may be present within them. You can see how from a veterinarian standpoint, we would be worried about the public and pet health risks associated with that, particularly if owners have young children or these pets are around the elderly who tend to be more immunocompromised. Extreme care must be taken into handling the pets’ excrement or fur and even kissing these pets as they may be more prone to having bacterial overgrowth particularly in their stool and their mouths.

Good sanitary hygiene with a pet’s fed raw foods is very important in reducing the transmission of bacterial contamination. Just as we don’t feed raw meats to babies and the elderly, we surely don’t want to feed it to young kittens or geriatric cats, particularly ones undergoing chemotherapy. One might also argue “But cats eat raw food in the wild.” Yes, wildcats, also known as lions, tigers and cheetahs eat raw foods. However, the cats we have here in our homes are domesticated and now live longer lives because of improvement in owner care, advancement of veterinary medicine, and an evolved diet.

Grain Free Diets

And then there are grain free diets. I must say that this has become such a mainstay in the pet food industry that now it’s become difficult to find a diet that isn’t grain-free. We’ve basically  been led to believe that grains are intrinsically bad because they cause allergies, lead to weight gain, cause seizures and etc with no sound scientific basis other than hearsay. Sure, cats can be allergic to certain carbohydrates in their diet, but they can also be allergic to proteins in their food.

What these grain-free diets promote is the idea that allergies come from grains, that there is an overabundance of pets with grain allergies running around. Nothing can be farther from the truth. My concern with grain-free diets is the following:

1. Grain-free diet manufacturers fail to mention that these diets are made in facilities where grain is also incorporated so there can be some cross contamination. 

2. There is new evidence showing that dogs (not so much in cats) on certain legume-based grain free diets may be more prone to dilated cardiomyopathy (heart disease) stemming from a deficiency in taurine (an amino acid).

3. Finally, the more you change your cat’s protein source, the harder it is for us veterinarians to put your possible food allergic cat on a novel protein and carbohydrate source because he/she has already been exposed to so many of them.

Yes, cats are obligate carnivores so you can NEVER make a cat vegan without detrimental consequences and proteins are essential and necessary for cats. However, grains also provide an abundance of minerals, vitamins, fiber, and energy as well. Grains have been singled out as the worst thing for pets when they still provide so many great benefits. Corn has been signed out as the most detrimental—deemed as a vile “filler” with no contribution other than weight gain.

It’s not the grain; it’s how much of it you’re feeding your pet. It’s the calories. Add the fact that cats sleep about 2/3 of the day and that’s how we get obesity. If you look at the nutrients in corn, it has vitamin C, fiber and B vitamins, so why are we so keen on demonizing this vegetable? It’s because somebody out there in marketing land deemed them to be the worst and now everyone thinks corn is the bottom of the barrel.

Prescription Diets

So what about prescription diets? Well, first of all, I don’t recommend them unless there’s an underlying condition your kitty has that requires it. But they can be beneficial. I think there’s a stigma that’s related to the word “prescription” and coupling it with the word “food.” People tend to like key buzzwords like “all-natural,” “organic,” “wholesome,” right? We equate it to “health,”  “vitality,” and “longevity.”

Much of what we recommend in medicine comes from years of research with a handful of information based on anecdotal evidence. What we know about your kitty’s health and medicine thus far has been gathered from years of rigorous study and decades of extensive research that is continually being updated (even as I’m typing this article). To be skeptical that prescription diets are not “healthy” is farther from the truth. We then have to ask ourselves “What is our definition of healthy?”

If we are trying to prolong our cat’s lives, I’d argue that prescription diets fall under the realm of “healthy” because they promote the “state of being free from illness.” They are backed by years of research to target your cat’s ailment and prolong your cat’s life as much as possible. That is the reason I recommend it when warranted. Now, getting your cat to eat it is another issue.

Closing Thoughts

All in all, what you feed your pet is all personal preference, but as a doctor, I deal with hard data and science and rely on this information to give my clients the best medical information possible. I, myself, feed my cats a commercial diet that is AAFCO certified to meet the requirements for a complete and balanced food. If you want to feed homemade food, by all means, go ahead. Just follow this website spearheaded by the UC Davis Nutrition Department to make sure you’re supplying everything in the right proportions to meet the needs of your kitty.

Hope this helps! Please let me know what you think in the comments section below. What works for you? What do you need you cats?


Dr. Theresa Loo

  • Reply
    October 20, 2018 at 9:05 am

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  • Reply
    Freddy Lim
    November 16, 2018 at 3:09 pm

    I have been absent for a while, but now I remember why I used to love this blog. Thank you, I will try and check back more frequently. How frequently you update your website?

  • Reply
    Pasadena Cat Portraits | A Vet and Her Cats | Greyboy Pet Prints
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    […] Don’t forget to check out Dr. Theresa’s to learn all about:• Non-anesthetic dental vs. dentals under general• Vaccination schedule for cats in the USA• Gifts for veterinarians• Traveling with your cat• Myths Debunked: Raw Foods & Grain Free Diets […]

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