Animals (human, and non-human alike) need nutrients to survive. They don’t need those nutrients to have come from some other poor animal, and carnists that insist that is the case are engaging in anti-science magical thinking. We can do amazing things with science, including synthesizing almost anything you can imagine.

However, last I looked around for plant-based dog food, it was pretty heavy on lentils, which I’ve heard can cause heart enlargement in dogs. Have further studies been done on this, or, have plant-based dog foods that don’t rely on lentils been made available?

FWIW, the lead author of this paper is an advocate for plant-based animal diets. Doesn’t necessarily make the study less valid. The data is what it is. But knowing the author is already of a particular mindset going into the study is worth understanding. Also worth noting, the paper is based on people filling out a questionnaire and is not a clinical study. Again, doesn’t mean the study is not valid, but I think it is good to understand.

My take away from reading it is that it seems like dogs can do well on an appropriate plant-based diet. But I think it is overstating the results to say that plant-based diets are better. At best I think you can say they are no worse than other diets. But even then, the sample size of respondents whose dogs were on a plant-based diet was much smaller than the other diets. They controlled for that statistically, but even so the study only included 336 plant-based dogs, which does not seem like a particularly large sample size.