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Home > Cats > Understanding Essential Amino Acids in Your Cat’s Diet: Vet-Reviewed Facts & FAQs

Understanding Essential Amino Acids in Your Cat’s Diet: Vet-Reviewed Facts & FAQs

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Dr. Luqman Javed

Veterinarian, DVM

The information is current and up-to-date in accordance with the latest veterinarian research.

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A cat’s diet is very important. Cats need to get the right balance of protein, fiber, vitamins, and minerals without consuming too many calories or carbohydrates. Because cats are obligate carnivores, they should get the majority of their nutritional requirements from meat sources, rather than plant-based sources.

Like all animals, cats need amino acids, which are the building blocks of protein, but they actually have a greater requirement for essential amino acids, which are those that must be obtained through diet because the body is unable to produce them itself.

There are 22 amino acids that your cat needs, and 11 of these are considered essential amino acids. What can you do to ensure that your cat is getting the right amount of these core nutrients? Let’s look a bit deeper.


What Are Amino Acids?

Amino acids perform many functions in the body but are described as being the building blocks of protein. They are responsible for everything from maintaining muscle to generating energy and even determining your ability to concentrate.

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Image Credit: Nils Jacobi, Shutterstock

All amino acids are composed of nitrogen, carbon, hydrogen, and oxygen. Although cats, like most animals, are capable of producing the majority of the amino acids they require themselves, there are some that they must get from their diet. These are called essential amino acids.

What Are Essential Amino Acids?

Essential amino acids must be obtained through diet because the body is not able to synthesize them. Despite this, they are vital to the growth and sustenance of various functions and systems.

Humans require 9 essential amino acids, while dogs need 10, but cats need 11. The 11 essential amino acids of cats are:

  • Arginine
  • Histidine
  • Isoleucine
  • Leucine
  • Lysine
  • Methionine
  • Phenylalanine
  • Taurine
  • Threonine
  • Tryptophan
  • Valine

While all of these essential amino acids are critical to survival, we will take a closer look at two in particular that are key to maintaining feline health.


Taurine is found in meat-based products and cannot be obtained from plant products. Cats use it to aid in vision, digestion, heart function, and throughout pregnancy to ensure proper fetal development. It is an essential amino acid, which means that your cat cannot naturally synthesize it, so they must get the taurine that they require from their diet. This is the only amino acid that’s essential for cats but non-essential for dogs, which is why cats should not be fed dog food on a long-term basis.

A taurine deficiency can take several months to show signs. When it does, it will usually start with trembles, a wobbly gait, weight loss, and difficulty seeing, as well as through heart conditions like dilated cardiomyopathy. Because taurine is also used in bile production, a deficiency in this essential amino acid can cause digestive complications.

In most cases, good quality cat food that is made from a decent meat source contains adequate levels of taurine. Your cat will get all the essential amino acids that they require, and you should not need to offer any other sources. Some foods are supplemented with additional taurine, further ensuring that your cat receives enough of this vital ingredient.

Please note that some fish don’t have taurine, so cats cannot be sustained on a fish-only diet for the long term. Raw fish isn’t recommended for cats (even those on a raw diet). The enzyme thiaminase found in many species of raw fish can lead to a thiamine deficiency in cats that consume raw fish.

There are no known incidents or problems associated with excessive taurine consumption, which means that it is generally considered safer to overfeed this amino acid than underfeed. If your vet has recommended that you supplement additional taurine into your cat’s diet, you should follow veterinarian guidelines or the guidelines on the supplement product.


Arginine is another essential amino acid for cats. Unlike most of the essential amino acids, your cat is actually able to produce arginine, but only in very limited amounts, and it is considered essential because it is not possible to increase the amount produced without adding it via diet.

blue Somali cat
Image Credit: Nataliya Kuznetsova, Shutterstock

Cats use arginine to convert ammonia into urea, a waste product, and deficiency can lead to diarrhea, vomiting, loss of weight, and ataxia. It can also cause hyperammonemia and aciduria. Feeding a diet with no arginine whatsoever can cause death quickly, such is the importance of this protein.

Like taurine, arginine is found in meat. In particular, it is found in muscle meat and is also found in eggs. Although arginine is found in dairy and some grains, cats are not recommended to be fed on these staples. Meat is the primary source of this amino acid for cats.

Good quality foods that feature meat as their primary ingredients should contain enough arginine to maintain a healthy diet for your cat, but you can look for foods with supplementary arginine.

You can also complement this information by knowing the quantity and calories to feed your cat with our calculator tool here:

The exact amount of calories an individual animal needs to maintain a healthy weight is variable and influenced by many factors including genetics, age, breed, and activity level. This tool is meant to be used only as a guideline for healthy individuals and does not substitute veterinary advice 



Amino acids are often referred to as the building blocks of protein. There are 11 essential amino acids for cats, which are those that must be obtained through dietary sources because a cat’s body is unable to naturally produce them. Arginine and taurine are just two of these acids but are two of the most important. If your food does not provide ample levels, you should consider changing to different cat food or supplementing to ensure that your cat remains healthy and strong.

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Featured Image Credit: Philippe Sonderegger, Shutterstock

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