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by tomweingarten 1816 days ago
Hi! I'm not a veterinary nutritionist, but I did used to teach metabolic biochemistry, and I spoke to a few veterinary nutritionists before putting my own dog on a vegan diet. Dogs are omnivores, so there are many vegan diet options dogs can live on healthily and happily. We like to think of dogs as friendly wolves, but they evolved a significantly different metabolism to co-exist with humans. I use a combination of Wild Earth and Bramble. Cats are obligate carnivores, so they require some chemicals (most notably Taurine) that don't naturally occur in plants. But there's no strong scientific barrier to us creating vegan cat diets through supplementation in the near future.
3 comments

I don't really understand why you're being downvoted, this was my understanding as well. There are plenty of vegan dog foods that seem to have a history of success and meet all AAFCO standards.

I think as far as vegan cat food, I'm not sure it will be healthy or feasible at scale until/unless there's something like Wild Earth's mouse-meat kibble based on cultured cells (under development, but no time frame given for expected completion).

I'd love to hear the opposing perspective, though.

It is very difficult to imagine a vegan diet for cats that has enough plant-sourced protein while remaining palatable. Most commercial cat food is far too high in carbohydrates and is usually high in fat. This increases the palatability and lowers costs but is not healthy for the cats.

Cats are picky eaters, and they can refuse foods even when starving.

> Dogs are omnivores

It may be technically true that animals like dogs and humans with meat-optimized digestive systems can survive off plant material alone, but that doesn’t mean it’s advisable. Neither of us can metabolize cellulose, both of us run into metabolic diseases with excessive carbohydrate consumption (e.g. diabetes), etc.

I mean, I think everyone agrees that way too much sugar or eating nondigestible plants is not a good idea.

But a vegan diet has been approved for humans at all stages of life, and the vegan dog food I'm aware of meets all AAFCO standards (nutrients, digestibility, protein:carb:fat ratio) as well as passing tests for dog interest/palatability.

There's a big difference between a well-rounded plant-based diet, and living off sugar or cellulose-heavy raw plants.

> eating nondigestible plants is not a good idea.

Almost every plant is nondigestible.

> But a vegan diet has been approved for humans at all stages of life

Well if it’s been “approved” then no need to worry! Who exactly “approved” it and why do I care what they say?

> There's a big difference between a well-rounded plant-based diet, and living off sugar or cellulose-heavy raw plants.

There are like 4 edible plants that don’t provide 90% of their calories in the form of sugars (starches are a kind of sugar). There are also very few plants that don’t have a huge cellulose content.