Taurine for Cats: What It Does and How Much They Need

Cats need taurine in their food every day, because their bodies can make only a little of it. Taurine supports normal vision, heart function, digestion and reproduction.

The reassuring part: a complete and balanced cat food that meets AAFCO's nutrient profiles already contains the taurine a healthy cat needs.

So if your cat eats a complete cat food, you're very likely covered already. The sections below explain why cats are different, how much taurine the food standards call for, and the few situations worth a closer look.

Why can't cats make their own taurine?

Taurine is an amino acid, one of the building blocks the body uses. Cats can make only a small amount of it themselves.

A 2023 review in the Journal of Animal Science and Biotechnology traces this to two enzymes. In cats, both work at low levels, so the body can't keep up with its own needs. The rest has to come from food.

That's why the Merck Veterinary Manual calls taurine an essential amino acid in diets for cats. Merck lists ten essential amino acids for dogs. Cats need those ten plus taurine.

Here's a small piece of history. Taurine was first isolated in 1827, from ox bile, and its name comes from Bos taurus, the Latin name for cattle.

The stakes are real, which is why pet food standards take it seriously. Merck notes that a long-term shortage can damage the retina at the back of the eye and weaken the heart muscle.

It's also why complete cat foods are built to carry enough, as the next sections show.

What does taurine do in a healthy cat?

The ASPCA describes taurine as important for normal heart function, vision and reproduction. The 2023 review adds skeletal and metabolic health to that list.

It also has a job in digestion that most people never hear about. Bile acids help the gut absorb fat. The body joins them to another molecule first, which makes them dissolve more easily in bile.

People use a mix of taurine and glycine for that step, roughly one to three. A 2020 study in Scientific Reports notes that in cats, bile acids are joined exclusively with taurine.

Taurine starts early. The 2023 review reports that a mother cat's milk has the highest concentration of taurine of any domestic mammal's milk. Kittens get it from the start.

How much taurine does a cat need?

For a cat on commercial food, the numbers that matter are in AAFCO's Cat Food Nutrient Profiles. A food formulated to these profiles must contain at least these amounts to be labeled complete and balanced.

Type of cat food	AAFCO taurine minimum
Dry (extruded)	0.10% of dry matter
Canned	0.20% of dry matter

"Dry matter" means the food with its water taken out, which lets a canned food and a kibble be compared fairly. AAFCO sets the same taurine minimums for growing kittens and for adult cats.

Why is the canned minimum twice as high?

AAFCO's table doesn't give a reason. One study offers a surprising clue. Researchers at UC Davis followed a labeled dose of taurine through cats fed the same commercial food, either heat-processed or frozen.

In the cats eating the heat-processed version, gut bacteria broke down far more of it: 9.4% of the dose was breathed out as carbon dioxide, against 0.09% on the frozen version.

The researchers concluded, in the Journal of Nutrition, that processing changes digestion in a way that lets gut microbes break down more taurine. The amount in the bowl and the amount a cat keeps can differ.

None of this needs working out at home. Cornell Feline Health Center explains that foods carrying the AAFCO statement are considered nutritionally complete and balanced. Look for that statement on the label, and the math is done for you.

Can cats eat dog food or a vegan diet?

Not as their main diet. The Merck Veterinary Manual states that cats can develop nutritional deficiencies when fed diets formulated for dogs.

Taurine is a clear example. AAFCO's cat profiles set a taurine minimum. Its dog food profiles list none at all, so a dog food has no obligation to carry the amount a cat needs.

Plant-based diets have a similar gap. Merck notes that plant proteins contain no taurine, which is why cats need some animal-based protein. The 2023 review is blunt: "all plant-sourced foodstuffs lack taurine."

Merck names homemade diets that aren't balanced, dog food and vegetarian diets as the most common routes to nutritional problems in cats. If a recipe hasn't been checked by a vet, it's worth that conversation.

For a kitten, a food labeled complete and balanced for growth covers taurine along with everything else. Our guide on what to feed a kitten walks through choosing one.

Does my cat need a taurine supplement?

For a healthy cat eating complete and balanced food, the veterinary sources point the same way. The ASPCA advises that a vitamin or mineral supplement is unnecessary on a complete diet unless a vet diagnoses a specific shortfall.

Cornell Feline Health Center goes further: supplements can be harmful and should never be given without your vet's approval. None of the ASPCA, Cornell or Merck pages cited here recommend extra taurine for a healthy cat on complete food.

So a supplement is optional at most, and your vet is the right person to set any amount. If you'd like to offer an occasional extra anyway, keep the main diet complete.

If you do, Choolip's Berry Good Milk is one option. It's lactose-free Grade A cow's milk with added lactase, and it contains taurine along with calcium, vitamins D3 and E, and omega-3.

It's an extra that sits on top of a complete diet and never replaces it. It is not a milk replacer and is never for newborn or orphaned kittens. Our article can cats drink milk covers how much is sensible.

Call your vet promptly if your cat:

• eats mostly dog food, a homemade recipe, or a vegetarian or vegan diet
• is pregnant or nursing and not on a food labeled complete and balanced for growth and reproduction
• shows any change in eyesight, energy or breathing, whatever you think the cause is
• is already taking a supplement a vet hasn't approved

Questions new cat parents ask

Is there taurine in all cat food?

A food formulated to AAFCO's profiles must meet the taurine minimum. AAFCO notes that snacks and foods for intermittent or supplemental feeding don't have to, so check for the AAFCO statement.

Do kittens need more taurine than adult cats?

AAFCO sets the same minimum for growth and for adults, as a share of the food. A kitten food labeled complete and balanced for growth covers it.

Is canned or dry cat food better for taurine?

Both work when they meet AAFCO's profile. Canned food has a higher minimum, and one study found gut bacteria break down more taurine from heat-processed food.

Can a cat get taurine from a vegan diet?

Plants contain no taurine. Merck notes a diet can be supplemented with synthetic taurine. Merck lists vegetarian diets among the common causes of nutritional problems in cats. Talk to your vet first.

Where does omega-3 fit in?

It's a different nutrient with different jobs. Our guide to omega 3 for cats covers what the research says.

Sources

• Merck Veterinary Manual: Nutritional Requirements of Small Animals
• AAFCO Dog and Cat Food Nutrient Profiles (Methods for Substantiating Nutritional Adequacy of Dog and Cat Foods)
• ASPCA: Cat Nutrition Tips
• Cornell Feline Health Center: Feeding Your Cat
• Li P, Wu G. Amino acid nutrition and metabolism in domestic cats and dogs. Journal of Animal Science and Biotechnology, 2023
• Miyazaki T, et al. Bile acid metabolism and taurine conjugation in taurine-depleted cats. Scientific Reports, 2020
• Hickman MA, Rogers QR, Morris JG. Effect of processing on fate of dietary taurine in cats. Journal of Nutrition, 1990
• Baliou S, et al. Protective role of taurine against oxidative stress. Molecular Medicine Reports, 2021

This article is for general information and is not veterinary advice. Talk to your vet about your own cat — they know the animal in front of them.