Are Carbs Bad for Cats? - Cat Info Detective

Are Carbs Bad for Cats?

Skye Blake-updated, white background

Greetings curious cats! Skye Blake here with answers to the question… “Are carbohydrates bad for cats?

Some people are concerned about cats eating things like wheat and potatoes.

So, let’s discover the facts…

paw prints coming in from a distance

Who Is Skye Blake?

Skye Blake-updated, white background

Skye Blake, Cat Info Detective, is a curious cat researcher (not a veterinarian) who sniffs out expert, reliable sources about cats, studies their information, then passes it on to you! 

Sometimes there’s not enough evidence for easy answers, so Skye gives you all sides, explains the situation as thoroughly and clearly as possible, and links you to experts on each page. 

All sources are at the bottom of each page so you can do more snooping. 

Carbohydrates (CHO) – Good or Bad?

whole grain bread, wheat, food, carbs

Carbohydrates have become a controversial topic in the cat food world, with some misunderstandings fueling certain claims about them.

What’s a Carbohydrate?

A carbohydrate is a molecule made up of carbon (C), hydrogen (H), and oxygen (O).

Carbohydrates are macronutrients that give your cat about the same amount of energy as protein.

heads of wheat - close up - litter, food, carbs

There are simple and complex carbs with distinct differences between them.

They also have fiber for good digestion and are in starches, sugars, and cellulose.

Cats eat carbs as starch (long branching chains of glucose molecules) but cannot eat sugar.

There are four types of carbs…

corn cob with kernels showing
  • Absorbable – (monosaccharides) a cat’s body digests these into glucose, galactose, and fructose and then absorbs them through the intestinal walls.
  • Digestible – carbohydrates that breaks down in the digestive system into usable forms of energy.
gold, white potatoes, food, carbs
  • Fermentable – the short chain sugars that easily break down in the digestive system (oligosaccharides, disaccharides, monosaccharides, polyols, etc.).
  • Nonfermentable (non-absorbable) are things like cellulose, bran, and lignin (structural components of plant cell walls). They don’t break down; instead, they travel through the intestinal tract intact.

Simple Carbohydrates

2 calico cats drink milk from bucket

The main difference between simple and complex carbs is that “simple carbohydrates are quickly digested and absorbed by the body whereas complex carbohydrates take time to be digested.” 1 “Difference Between Simple and Complex Carbohydrates | Definition, Digestion, Absorption” (

Simple carbs are sweet and are in foods like milk, fruit, and vegetables (things we cats can’t eat).

They have names like glucose, fructose, lactose, and sucrose.

Complex Carbohydrates

yuca (cassava) root peeled, carbs, food, litter

“Complex carbohydrates are more slowly digested and take time to absorb [in]to the body.

Green vegetables, starchy vegetables such as potatoes and corn, peas, lentils, beans, whole grain and food produced by the whole grain are composed of complex carbohydrates.” 2Difference Between Simple and Complex Carbohydrates | Definition, Digestion, Absorption” (

corn kernels used in cat litter, food, carbs

Fortunately for most cats, digesting grain and other complex carbs isn’t a problem when in small amounts.

But too much can cause some digestive upset like gas or vomiting.

Benefits of Carbohydrates in Cat Food

feed corn kernels, cat food, carbs

The various sources of carbs in good quality cat food are typically complex like whole grains and potatoes.

They give us other nutrients as well, like antioxidants, fiber, omega-3 and omega-6 fatty acids (among others), vitamins and minerals.

For example, wheat and beans are high in protein, while oats are high in soluble fiber.

Sweet potatoes have a lot of potassium and beta-carotene.

sweet potatoes, carbohydrates, food

Fiber in various carb sources helps us have healthy gut bacteria and makes our poop nice!

Feline nutritionists who formulate pet food include grains and other carb sources to provide nutrients and fiber, not as fillers.

Misunderstandings About Carbohydrates

Carbs, Fats & Calories… Oh My!

cat licking mouth

A common misunderstanding about carbs is that they make cats fat.

This isn’t true… weight gain comes from eating too many calories, not carbohydrates.

Carbohydrate sources, like grains and vegetables, have more calories than proteins but half as much as fats.

longhaired grey, white cat eating kibble by glass of water, food

So, a high-protein, low-carb diet may actually have more calories because there are more fats.

Replacing fats with carbs is one method nutritionists use to deal with obesity and manage diabetes.

Carbs & Diabetes

kibble (dry) cat food in bowl, carbs

There’s a misunderstanding about carbohydrates and diabetes.

The truth is that carbohydrates don’t cause diabetes but can be helpful in managing it.

If your cat has a specific medical condition like Diabetes Mellitus, your vet or vet nutritionist can help you determine the amount and types of carbohydrates to include in your cat’s diet.

Discover more at “Dry Cat Food (Kibble)“.

How Well Do Cats Digest Carbohydrates?

black cat upside down with canine teeth showing, waiting for food, carbs

There’s a popular theory that cats can’t digest carbs based on the fact that their natural prey contains only small amounts of whatever plants they happen to have in their stomachs.

However, as often happens, the evidence shows something different.

tabby, white kitten stretched out on back lounging

“Early studies by Morris et al. observed that adult cats could efficiently digest all carbohydrates added to a meat-based diet, despite the described evolutionary adaptations along the feline gastrointestinal tract…

The total apparent digestibility of starch is reported to be 40–100%, depending on source and treatment…, which proves that cats can digest and absorb carbohydrates.” 3Cats and Carbohydrates: The Carnivore Fantasy? – PMC (

2 dark tabby cats eating from same dish, carbs

“As in other mammals, proper processing and cooking is necessary.

Carbohydrate sources are not provided to cats as raw ingredients.

Typically, carbohydrate sources are ground and cooked during the extrusion or canning process, which improves digestibility.” 4Cats and Carbohydrates: The Carnivore Fantasy? – PMC (

dark tabby cat lounging in dining chair, waiting for food, carbohydrates

“Poorly digestible carbohydrates or excessive amounts of highly digestible carbohydrates that are not digested in the small intestine provide substrate for microbial fermentation in the colon.

High carbohydrate intake in cats therefore increases colonic and faecal organic acid concentrations and reduces faecal pH…

Also, adverse digestive effects, such as diarrhoea, flatulence and bloating, may be induced…” 5 Cats and Carbohydrates: The Carnivore Fantasy? – PMC (

2 tabby cats running, chasing

“The vast majority of carbohydrates in pet foods are provided by plant-sourced ingredients.

Digestible carbohydrates are separate from fiber, which while biochemically is considered a carbohydrate, cannot be digested by the digestive enzymes in pets’ guts, and is instead utilized to varying extents by their gut microbes.” 6 Carb Confusion Part 1: The Role of Carbohydrate in Pet Foods – Clinical Nutrition Service at Cummings School (

Can Carbohydrates Cause Health Problems?

breakfast rolls, wheat, carbs

The only evidence of health problems involving carbohydrates is what we just discussed about calories and digestive upsets.

Beyond that there’s no evidence that carbohydrates, even in high amounts, cause any health problems for cats.

As long as the food is complete and balanced the amount of carbs doesn’t seem to make any difference.

sick cat vomiting the food

There are also claims that many cats are allergic to carbs but there’s no evidence this is true.

True food allergies are rare in cats and are usually related to animal-based proteins not than plant-based ones.

If you think your cat has digestive problems or possible allergies, have your vet do a health check and discuss the situation before making any food changes.

Tabby cat eating from plastic bowl

This is an important step because it’s a complex process to diagnose any true food allergies.

Discover more at “Cat Food Allergies & Sensitivities“.

Now that you’ve discovered the scoop about carbs, check out more about cat food and nutrition at “Cat Food!


Sources used on this website are either primary or secondary.

Primary sources are always preferable and have the most reliable information because they’re original and directly referenced.

Scientific abstracts and data are good examples of primary sources.

Secondary sources are weaker because they usually consist of opinions or articles that give no sources of their own. Sometimes they refer to primary sources.

When I use secondary sources, most are those with some authority, such as veterinarian or cat behaviorist books and articles.

List of Sources

Carb Confusion Part 1: The Role of Carbohydrate in Pet Foods” – Clinical Nutrition Service at Cummings School (

Carb Confusion: Part 2 – Measuring and Comparing Carbohydrate in Pet Foods” – Clinical Nutrition Service at Cummings School (

Cat Nutrition: Guide to Cat Food Nutrients“, PetMD

Cats and Carbohydrates: The Carnivore Fantasy?” – PMC (

“Dietary Carbohydrates are NOT “Toxic” to Cats”,

Difference Between Simple and Complex Carbohydrates | Definition, Digestion, Absorption” (

Digestion and Absorption of Carbohydrates, Proteins and Fats” by Sagar Aryal,, March 25, 2022

Everything You Need To Know About Nutrient Bioavailability“, Nutrova, April 5, 2021

Front Matter | Nutrient Requirements of Dogs and Cats“, The National Academies Press

What Are Fermentable Carbohydrates?” By Janet Renee, MS, RD,

What’s a carnivore?” – nutrition rvn

Updated April 12, 2024

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