Are cats obligate carnivores?

Yes. ASPCA veterinary guidance states cats are obligate carnivores: their metabolism requires nutrients obtained from animal tissues, including taurine, which cats cannot synthesize adequately.

Why are vegan cat diets risky?

Without adequate taurine and other animal-dependent nutrients, cats can develop dilated cardiomyopathy and retinal disease. MSD Veterinary Manual notes taurine-responsive DCM historically drove fortification of commercial cat foods; noncommercial diets (including vegetarian/home-cooked) remain a risk setting.

Are cats carnivores?

Short answer: yes — obligate carnivores. Dogs are more metabolically flexible (often described as facultative carnivores / scavengers), but that does not mean a plant-only diet is automatically complete for either species without careful, specialist formulation.

Sources: ASPCA · MSD Vet Manual (DCM) · Pion et al. 1987 (PubMed)

Cats: obligate carnivores

Per ASPCA, cats need meat-sourced nutrition to thrive. Their gastrointestinal tracts and metabolism are adapted to animal prey — they are not designed around a plant-based staple diet.

Taurine — the hard requirement

Taurine is an amino acid essential for cats. ASPCA notes cats cannot synthesize it the way humans and dogs can, and must obtain it from the diet; plant foods do not provide it. Deficiency can cause dilated cardiomyopathy (DCM) and severe eye disease, including blindness.

The clinical landmark is Pion et al. 1987, which linked feline DCM to taurine deficiency (PubMed 2951927). MSD Veterinary Manual states incidence of feline DCM fell dramatically after that discovery as taurine was added to commercial cat foods; most feline DCM today is not taurine-responsive, but the disease still occurs occasionally in cats fed noncommercial diets (examples given include vegetarian food, baby food, and home-cooked food).

Dogs: more flexible, not “herbivores”

Dogs can synthesize taurine more readily than cats (ASPCA contrast). That metabolic flexibility is why dogs are not labeled obligate carnivores in the same way — not because a random vegetarian recipe is automatically complete. Completeness still requires meeting canine nutrient profiles (see our homemade diet evidence page).

Educational only — not veterinary advice. Diet changes for sick or at-risk pets belong with your veterinarian (and a board-certified veterinary nutritionist when homemade or complex diets are considered).