Cat Nutrition: What Makes a Nutritional Cat Food?

Jennifer Coates, DVM
By Jennifer Coates, DVM on Feb. 15, 2021
Cat eating

One of the best ways to keep cats healthy and happy is to feed them well. Cats need all the right nutrients in just the right proportions to grow, maintain their bodies, be active, and prevent and recover from illness or injury.

With healthy eating being so essential, pet parents need to know what goes into finding the best cat food. Here is breakdown of what you need to know about cat nutrition.

Cat Nutrition 101: What Are the Essential Cat Nutrients?

Nutrients are components of the diet that perform specific jobs in the body. Cats can get the nutrients they need from a variety of ingredients. For example, calcium (a nutrient) can come from ingredients like bone, bone meal, dairy products, organ tissues, meat, legume plants, and a mineral supplement.

Nutrients fall into one of six categories:

  • Protein

  • Fat

  • Carbohydrate

  • Vitamin

  • Mineral

  • Water

Energy is not technically a nutrient, but it is still an important part of a cat’s diet. Dietary energy, measured in kilocalories (also called calories), comes from fats, proteins, and carbohydrates.

Which Cat Foods Have All the Essential Nutrients?

An easy way to ensure that cats get all the nutrients they need is to only purchase foods that have an Association of American Feed Control Officials (AAFCO) statement of nutritional adequacy on their labels.

Look for something along the lines of one of these two sentences:

  • Animal feeding tests using AAFCO procedures substantiate that Yummy Cat Food provides complete and balanced nutrition for adult maintenance, growth and reproduction, or all life stages.

  • Yummy Cat Food is formulated to meet the nutritional levels established by the AAFCO Cat Food Nutrient Profiles for adult maintenance, growth and reproduction, or all life stages.

Now let’s take a closer look at the role that nutrients play in a cat’s body.

Protein in Cat Food

Cats are carnivores and need to eat a lot of protein in comparison to many other animals. Dietary protein is used to develop and maintain muscle, skin, fur, nails, tendons, ligaments, cartilage, enzymes, hormones, antibodies, and more.

In cats, protein is also an important source of energy.

Plant vs. Animal Protein

Cats need animal protein because their bodies need the nutrients it provides. When a cat eats protein, their digestive tract breaks it down into building blocks called amino acids, which are then reassembled into the type of protein that the cat needs at that time.

A cat’s body can make many of the amino acids they need (nonessential amino acids) from other amino acids, but there are 11 essential amino acids for cats that must be supplied in a cat’s diet:

  1. Arginine

  2. Histidine

  3. Isoleucine

  4. Leucine

  5. Lysine

  6. Methionine

  7. Phenylalanine

  8. Taurine

  9. Threonine

  10. Tryptophan

  11. Valine

These essential amino acids, as well as other essential nutrients for cats, are best supplied by meat and other animal tissues, which makes sense when you think about it. Why should the body waste resources making nutrients that are abundant in the prey animals that cats evolved to eat?

What Does Crude Protein Mean?

Protein, especially animal protein, is expensive. Some cat food manufacturers keep costs low by including only the minimum amount of protein that cats require to survive, not more to help them thrive.

A cat food’s crude protein level should be included in the guaranteed analysis section on the label. Crude protein is an estimate of a diet’s protein level that is determined by measuring the amount of nitrogen present.

By looking at crude protein levels, you can compare how much protein different cat foods contain. However, you’ll need to do some calculations to compare a dry food to a wet food. You’ll also need to do some simple math to see whether a cat food meets or exceeds the amount of protein a cat needs.

How Much Protein Does My Cat Need?

To be considered nutritionally complete and balanced, AAFCO mandates that a cat food for adult maintenance contain a minimum of 26% crude protein on a dry matter basis. The minimum for growth and reproduction is 30%.

You’ll need to do some math to convert the “as fed” crude protein levels listed on most cat food labels into dry matter levels:

  • Find the percent moisture in the guaranteed analysis and subtract that number from 100. This is the percent dry matter for the food.

  • Divide the crude protein percentage by the percent dry matter for the food and multiply by 100.

  • The resulting number is the crude protein percentage on a dry matter basis.

When it comes to protein, more than the AAFCO minimum is almost always better for cats. Research has shown that a diet that provides around half of its calories from crude protein fits with what cats seek out when left to their own devices.

Can Cats Be Allergic to Certain Proteins?

Protein can be problematic; too much protein, particularly low-quality protein, can worsen symptoms associated with kidney disease in cats.

Proteins are also the primary trigger for food allergies in cats. If your cat has health problems, be sure to discuss what type of cat food would be best with your veterinarian.

Fat in Cat Food

While proteins are an important energy source for cats, fat is the most energy-rich nutrient in the diet. Fats also act as transport molecules, and they help conduct nerve impulses.

Essential omega-3 and omega-6 fatty acids are also important for skin and coat health, wound healing, and inflammation.

Sources of Fat

Fat and essential fatty acids are part of ingredients like salmon, chicken, liver, or beef that are included in cat foods.

Sometimes extra fat is added to a diet, and in these cases, you will see fat sources specifically noted in the ingredient list—beef fat, fish oil, or soybean oil, for example.

What Does Crude Fat Mean?

A cat food’s crude fat level will be listed in the guaranteed analysis section on the package and is estimated by extracting the fats that are present using ether.

How Much Fat Does My Cat Need?

The AAFCO minimum for fat in all cat foods is 9% on a dry matter basis.

Significantly higher levels of fat may be appropriate for cats who are highly active or have trouble maintaining their weight. Diets designed for weight loss will usually contain less fat in comparison to adult maintenance cat foods.

Carbohydrates in Cat Food

For many animals, carbohydrates are important sources of energy, but this is less true for cats since they have evolved to get most of their energy from protein and fat.

Even though cats can digest small amounts of carbs and use them for energy, they should play just a small role in a cat’s diet.

Sources of Carbohydrates

A diet containing large amounts of carbohydrates is not natural for cats and may promote weight gain and related health problems, like diabetes.

Studies have shown that cats with food allergies may also react poorly to certain carbohydrates, although this is less common than being allergic to ingredients like beef, chicken, or fish.

How Many Carbs Does My Cat Need?

Ideally, cats should get less than 10% of their calories from carbohydrates.

Dry diets require relatively high levels of carbohydrates to maintain their form, so this level can only be met in wet foods. Feeding wet food only is a simple way to reduce your cat’s carb intake.

Vitamins in Cat Food

Vitamins are organic compounds (meaning they contain carbon) that are necessary in small amounts in the diet. Without vitamins, many enzymes (substances that promote chemical reactions) that are essential for normal feline metabolism could not function.

Sources of Vitamins

Vitamins are found naturally in many cat food ingredients, including animal tissues, vegetables, fruits, vegetable oils, seeds, and grains.

However, it is almost impossible to provide all the vitamins a cat needs at just the right levels without including a vitamin supplement in the manufacturing process.

Which Vitamins Do Cats Need?

According to AAFCO, cat foods should contain the following vitamins:

  • Vitamin A: Important for vision, bone and tooth growth, reproduction, and maintenance of skin and mucous membranes

  • Vitamin D: Increases blood calcium and phosphorous levels to support growth and maintenance of bones

  • Vitamin E: An important antioxidant

  • Vitamin K: Necessary for normal blood clotting

  • Thiamin: Plays a role in carbohydrate metabolism

  • Riboflavin: Releases energy from carbohydrates, fats, and proteins

  • Pantothenic Acid: Needed for metabolism of carbohydrates, fats, and some amino acids

  • Niacin: Necessary for processing fats, carbohydrates, and protein

  • Pyridoxine: Helps metabolize amino acids, glucose, and fatty acids

  • Folic Acid: Needed for synthesis of DNA and the amino acid methionine

  • Biotin: Helps make fatty acids, some amino acids, and DNA/RNA

  • Vitamin B12: Required for fat and carbohydrate metabolism and nerve conduction

  • Choline: Essential as a neurotransmitter, as part of cell membranes, and for lipid transport

Do Cats Need Vitamin Supplements?

As long as a cat is healthy and eating a nutritionally complete and balanced cat food, additional vitamin supplementation is not necessary, and under some circumstances, may actually be dangerous.

Talk to your veterinarian if you think your cat could benefit from a vitamin supplement.

Minerals in Cat Food

Minerals are inorganic compounds (meaning they do not contain carbon) that are required in the diet if the body is to function normally.

Sources of Minerals

Some of the minerals that cats need can come from animal and plant-based ingredients (bone meal, for example), but to be nutritionally complete and balanced, cat food manufacturers almost always have to add mineral supplements to their formulas.

As long as your cat is healthy and eating a food labeled with an AAFCO statement of nutritional adequacy, you should not have to provide additional supplementation on top of that.

Which Minerals Do Cats Need?

According to AAFCO, the following minerals must be present in a cat food in sufficient amounts:

  • Calcium: Vital for the growth and maintenance of bones and teeth and as an intracellular messenger

  • Phosphorus: Essential for the growth and maintenance of bones and teeth and vital to normal metabolism

  • Potassium: An electrolyte that’s important for nerve function, muscular contraction, and heart rhythm

  • Sodium and Chloride: Electrolytes that help with hydration, acid-base balance, transmitting nerve impulses, and muscle contraction

  • Magnesium: Important for enzyme function and the metabolism of carbohydrates, protein, and fats

  • Iron: Needed for oxygen transport throughout the body

  • Copper: Plays roles in iron absorption and transport, skin pigmentation, and skeletal growth

  • Manganese: Important for metabolism, immune function, and bone formation, as well as acting as an antioxidant and more

  • Zinc: Necessary for carbohydrate, lipid, protein, and nucleic acid metabolism

  • Iodine: Needed to make thyroid hormones

  • Selenium: An important antioxidant that works in conjunction with vitamin E

What Are Chelated Minerals?

Minerals are inorganic substances that are sometimes difficult for animals to absorb from food.

Chelation is a process that binds a mineral to an organic substance like an amino acid. Chelated minerals may be more easily absorbed and used by cats than nonchelated minerals.

Water in Cat Food

Now on to the most important nutrient for cats—water.

Water makes up most of a cat’s body and is essential to almost every metabolic function. Domestic cats have evolved to get most of their water from their food, not from a water bowl.

Cats will typically let themselves become more dehydrated (8%) in comparison to dogs (4%) before seeking out a drink of water.

What Is Water Sufficient for Processing?

Some ingredients, like whole meats, are rich in water. Water is also added to commercial cat foods as part of the manufacturing process to facilitate mixing. You may see this on the ingredient list as “water sufficient for processing.” Most of the water is subsequently driven out of dry foods to make them more shelf stable.

Canned foods contain much more water than do dry foods, which makes canned food a better match for the way cats prefer to get their water and an overall healthier choice.

How Much Water Does My Cat Need?

Healthy cats generally need to take in around 4 to 5 ounces of water per 5 pounds of body weight, but this includes both what they get from their food and from a water bowl. Cats who eat canned food only may need to drink very little supplemental water.

Can I Make My Own Nutritional Cat Food?

The safest and simplest way to meet a cat’s nutritional needs is to feed them a high-quality, AAFCO-approved canned cat food.

But what about making your own cat food? Yes, homemade cat foods can be a nutritious option, but they require a lot of extra effort, time, and money.

If you’re interested in a homemade diet for your cat, schedule a consultation with a veterinary nutritionist or make use of services like or that are run by veterinary nutritionists.

Do not make cat foods from recipes you find online or in books. Research has shown that they are rarely nutritionally complete and balanced.

Featured image:

Jennifer Coates, DVM


Jennifer Coates, DVM


Dr. Jennifer Coates is an accomplished veterinarian, writer, editor, and consultant with years of experience in the fields of veterinary...

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