People make decisions about what to eat based on their beliefs and backgrounds, including health, political, environmental, cultural, or religious ideals. For some people, that carries over into what they choose to feed their dogs and cats. In one study, 100% of people who fed cats a vegetarian diet reported eating vegetarian diets themselves.
Amy Short from Brooklyn, N.Y., tells WebMD that she began feeding her domestic shorthaired cats, Olive and Georgia, a commercial vegan diet as 3-month-old kittens. “Because I am a vegan, I strive to live my life as compassionately as possible,” she says. “I had real dissonance with the idea (and brief practice) of buying animal-based food for my pet animals.”
Besides a little dental trouble for Georgia and springtime allergies for Olive, Short says the cats, which are now 8 years old, are “healthy, happy.”
Short says she hasn't gotten much pushback from veterinarians, in part because she hasn’t told some of them about the cats' vegan diet.
But feeding dogs and cats a no-meat diet is controversial and can be risky. Here's what you need to know if you're considering it.
Lew Olson, PhD, author of Raw and Natural Nutrition for Dogs, makes this analogy: “Trying to feed a cat a vegan diet would be like me feeding my horses meat. You’re taking a whole species of animal and trying to force it to eat something that it isn’t designed to handle.”
“For cats, it’s really inappropriate. It goes against their physiology and isn’t something I would recommend at all," says Cailin Heinze, VMD, a board-certified veterinary nutritionist and assistant professor of nutrition at Tufts Cummings School of Veterinary Medicine.
"For dogs, certainly vegetarian and vegan diets can be done, but they need to be done very, very carefully. There is a lot of room for error, and these diets probably are not as appropriate as diets that contain at least some animal protein," Heinze says.
Vegetarian Dog and Cat Food Risks
Dogs and cats process certain nutrients differently than people do. Here are two examples:
Vitamins A and D: Dogs and cats cannot make vitamin D in their skin, so it needs to be in their diet. And the vitamin D needs to be D3, which comes from animal sources, not D2, which comes from plant-based sources. “People and dogs can use D2 to some extent, but cats really need D3,” Heinze says.
Taurine. Dogs can make taurine if provided the right building blocks through dietary protein. Cats cannot make their own taurine at all, so it is regarded as an essential amino acid in this species and must be present in adequate amounts in the diet. Both species can suffer taurine deficiencies.