Is Grain-Free Cat Food Better?

Matthew Everett Miller, DVM
By Matthew Everett Miller, DVM on Jan. 18, 2021

It goes without saying that as a cat parent, you want your feline friend to enjoy a life that’s as long and as pleasant as possible. A huge part of supporting your cat’s health is ensuring that they have the right nutrition.

As a result, selecting a cat food is a pretty important decision. This is compounded by the fact that there are now tons more cat food options than ever before.

Many pet owners are turning to the increasingly abundant offerings of trendy pet foods: vegan, vegetarian, raw, holistic, organic, human-grade, limited-ingredient, freeze-dried, and grain-free cat food.

Although each of these diets has its pros and cons, grain-free pet foods, especially grain-free cat foods, have proven to be among the most popular and most polarizing developments in pet nutrition in the last 20 years.

But is grain-free cat food really as good for your cat as it seems? Here’s everything you need to know about grain-free cat food.

What Does Grain-Free Cat Food Mean?

Unlike many other terms used on pet food packaging, “grain-free” does have a specific, regulated definition.


Grains are the fruit of grass plants. The term “grain” includes:

  • Barley

  • Corn

  • Oats

  • Rice

  • Rye

  • Wheat

Grain By-Products

You may also see these grain by-products listed on an ingredient label, which indicate the presence of grain:

  • Bran

  • Gluten

  • Hull

  • Flour

  • Starch

If a cat food contains none of these ingredients, that food is “grain-free” by definition.

Is All Grain-Free Cat Food Also Gluten-Free?

Gluten is the protein component of grain, so all grain-free cat food is also gluten-free cat food by default.

Be aware that although gluten allergies and sensitivities are a widely discussed topic in human nutrition, these allergies are exceedingly rare in cats, and food allergies of any sort are also uncommon.

Therefore, pet foods labeled as gluten-free or grain-free are not intrinsically healthier or better for your cat. Conversely, the presence of gluten, grain, or grain by-products in cat food does not necessarily speak to the quality of that diet.

Are Grain-Free Diets Dangerous for Cats?

For cats and their owners, grain-free diets do not pose a health risk. Although there is a suggested link between grain-free dog food and canine heart disease, no such link appears to exist in cats.

How Grain-Free Cat Foods Became Popular

Until recently, grain-free cat food diets were found mostly in the realm of specialists. Veterinary nutritionists and dermatologists might recommend foods with no grains as part of a treatment plan for cats with unusual sensitivities, allergies, or other inflammatory conditions.

After the rise of low-carb diet fads for people in the early 2000s, the pet food industry had a health halo effect in which people assumed that the perceived health benefits of a diet made for people would also apply to pets if they were fed that same diet. We saw a surge in pet foods that were high in protein and low in carbs.

In the 2010s, when gluten-free offerings began proliferating across restaurants and grocery stores in North America, pet parents also started looking for grain-free pet food. 

In these grain-free diets, ingredients like corn and rice were swapped for nongrain carbohydrate sources like potatoes and legumes.

Do Cats Need Grain-Free Food?

Absolutely not.

The argument in favor of grain-free cat food was simple: cats in the wild don’t eat grain. You don’t see lions munching on wheat. So, if my cat is descended from wild cats, why does he need grain at all?

However, the assumption that wild animals naturally eat a diet that is perfectly suited to their nutritional needs is not entirely accurate.

Although wild cats and dogs do not typically ingest starches, dietary studies show that domestic dogs and cats can nonetheless digest more than 95% of starches.

Grains are added to pet food not as fillers, but as a cost-effective and easily digestible source of vitamins and energy. When grains are added to cat food, there are no discernible ill effects and no reduction in a cat’s quality or length of life.

What About Cats With Grain Allergies?

Cats that have been diagnosed with allergies to a grain like rice, corn, or barley should of course eat a diet that’s free of those ingredients.

However, because food allergies are best diagnosed by intradermal allergy testing or expensive blood testing, many pet parents who believe their cat has allergies are relying on their own assumption or a suggestion of possibility by a friend, trainer, breeder, or veterinarian.

Food allergies in general are much rarer than pet parents believe, and grain allergies are present in a vanishingly small portion of those animals that do truly possess food allergies. Allergies to animal proteins such as chicken or fish comprise the majority of food allergies in cats.

If your cat has not been diagnosed with a grain allergy by a veterinary dermatologist or other professional, talk to your regular veterinarian about any symptoms your cat is having that make you worried about food allergies, such as:

  • Hair loss

  • Itchiness

  • Scabs on the skin

  • Intestinal issues

They will be able to make sound recommendations about the role that diet might play in your cat’s condition.

Should You Choose a Grain-Free Cat Food?

In specific circumstances, such as cats with documented food allergies, IBD, or other inflammatory conditions, grain-free diets can offer some benefit, as can any diet with ingredients tailored to a specific cat’s dietary sensitivities and needs.

But for the vast majority of cats, especially those that seem to be in perfect health, grain-free cat food diets are not necessary for your cat to be healthy.

Traditional diets such as kibble-based dry foods and canned foods are generally formulated based on nutritional studies that seek to answer the question: what can we feed cats that will minimize health issues and promote a long and happy life?

When it comes to high-quality pet foods, price does not correlate perfectly with quality, so you can’t choose a cat food solely based on the price. It’s best to talk to your veterinarian about the best food options for your particular cat based on their needs, age, and health conditions.

Featured image:

Matthew Everett Miller, DVM


Matthew Everett Miller, DVM


Matthew Everett Miller is a Kentucky native, veterinarian, and writer whose fiction and journalism have appeared in Slate magazine, the...

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