Are Cats Obligate Carnivores? Why Do They Need Meat?

Plant-based diets are popular with people, and many dog owners are interested in adding more fruits and vegetables to their dog’s diet. Dogs are omnivores like us, which means they can eat both meat and plants. But before you think about changing your cat’s diet, you should know a few important facts about the specialized nutritional needs of cats. Your domestic cat is what’s known as an obligate carnivore, just like lions and tigers. Let’s look at what an obligate carnivore is, and what that means for your cat’s diet and overall health.

What is an Obligate Carnivore?

An obligate carnivore, also sometimes called a strict carnivore, is an animal that has to eat a diet that consists of animal proteins to get all of the nutrition it needs to survive. All cats, wild and domestic, are obligate carnivores. Studies of feral domestic cats have shown that the bulk of their diet is made up of small rodents, birds, insects, and even frogs. Foods that do not consist of animal protein are not a healthy dietary choice for cats. They need certain nutrients that come from meat sources only. While it is possible for humans, and even dogs, to metabolize certain important nutrients from plants, cats can only absorb all the nutrients they need from meat. Why is this?

Why Do All Cats Need to Eat Meat?

Cats have a long evolutionary history of eating a meat-only diet. They cannot process nutrients from plants in the same way we do. Their bodies are not designed to digest plant-based starch, sugar, and carbohydrates the way omnivores can. A cat’s digestive system can be easily upset by certain vegetables that you might see in dog food, for example. The most important reason why cats need to eat animal protein has to do with how cats make vital nutrients in their bodies or process them from outside sources. There are certain substances that cats and other animals can either manufacture in their bodies or, in some instances, get from plants. But some very important nutrients that are critical to a cat’s survival are not made in the body and can only be obtained through eating meat. What are some of these substances that cats need to get from a meat diet? Here are a few:

Many of these dietary components are critically important to cats. You may have heard of taurine in connection with feline nutrition. Let’s look at taurine and a few other nutrients that cats must get through eating meat.

What is Taurine for Cats?

Taurine is an amino acid that is only found in animal protein. It is essential for healthy bodily function. Unlike other animals, cats cannot make taurine, so they must regularly get it from the animal proteins they eat. Lack of enough taurine causes serious health problems in cats, including degeneration of the eyes and heart, as well as abnormal development in kittens. Most commercial cat food diets contain enough taurine to keep your cat healthy, so there’s normally no need for supplements unless your cat requires it as a veterinary treatment to reverse damage from too little taurine in the diet.

Why Do Cats Need Cystine?

Cystine (sometimes called cysteine) is an amino acid that is required to produce a unique compound found in cats called felinine. Felinine is a substance that is excreted in the urine, particularly in male cats. Like pheromones, felinine is used for scent communication between cats, especially territory marking. It is part of the reason why cat urine has a famously distinctive and pungent smell.

Why Do Cats Need Arginine?

One other vital component of the feline diet is arginine. Arginine is an essential amino acid that cats can only get from eating animal protein. Arginine is vital in helping your cat remove ammonia from the body. Ammonia is a waste product that comes from broken-down proteins and must be eliminated. Lack of arginine can cause serious problems, even after just a couple of deficient meals. Symptoms include lethargy, vomiting, and convulsions.

What is the Best Diet for Cats?

Now that we’ve seen why cats are obligate carnivores and must eat animal protein to survive, what type of food is best for cats? Commercial cat foods are designed to give your cat the right balance of essential nutrients. Cat food manufacturers use a set of established standards. All foods will have at least the basic minimum standards, some have higher. You can read the nutritional information and the ingredients list on the label of your cat’s food. Choose a food that is made for your cat’s life stage (and health if you are feeding a veterinary diet). You also want to make sure that animal proteins are the first ingredients listed. A cat’s complicated nutritional requirements are the reason why most veterinarians do not recommend that your feed your cat a homemade diet. An occasional homemade treat like a bit of plain cooked chicken or fish is fine, though. If you have any questions about your own cat’s nutritional needs, be sure to talk to your veterinarian for advice.

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