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"Cats can't be vegan."
They make claims about the body or nutrition that the evidence does not support. When they fall, they take the speaker's credibility with them.
Why it is weak
Many vegans repeat this as if it were established fact, but the available evidence points the other way. In a study of 1,369 cats published in PLOS ONE in 2023, the 127 fed a vegan diet tended to be as healthy or healthier on all seven general indicators, and a 2021 study of more than a thousand cats in Canada and the US also found no harm. A vegan cat food tested at the Federal University of Lavras, in Brazil, met the cats' needs on the measures assessed.
What a cat needs is nutrients, not meat. Taurine, preformed vitamin A and arachidonic acid can be supplied synthetically, and the taurine in ordinary cat food is already synthetic. No extruded dry food is "natural".
If current foods aren't enough for some cat, that's a food engineering problem to solve, not an impossibility. Precision fermentation and cultivated meat already produce ingredients without killing animals: the UK approved cultivated meat in pet food in 2024.
The chickens, cattle and fish that become cat food want to live too, and there are many of them. Saying cats can't be vegan closes the door on saving those animals before even trying.
How to say it better
The evidence suggests cats can live well on complete vegan foods, carefully formulated and with veterinary follow-up. Where that still falls short, the answer is to develop better foods, not to give up on the animals that become cat food.
What the studies support is "may be adequate", not "proven to be better": the data come from owner reports, most differences were not statistically significant, and the Lavras study used only 18 cats. An unformulated home-made diet is risky, with or without meat, and a cat may refuse a particular food.
See also
Sources and further reading
- Can cats be vegan? What science says (in Portuguese)
- Vegan versus meat-based cat food: guardian-reported health outcomes in 1,369 cats
- A cross-sectional study of owner-reported health in Canadian and American cats fed meat- and plant-based diets
- The Impact of Vegan Diets on Indicators of Health in Dogs and Cats: A Systematic Review
- Meatly gets UK approval for use of cultivated meat in pet food