Summary
- Carnivore is a classification, not a diet requirement.
- The amount of meat that cats eat is significant. Transitioning domestic cats to eating vegan would do much good for the environment and animal welfare.
- Having vegan cats now is not convenient, but we (humanity) should make that so.
- We do not need to wait around for cultivated meat. There are tractable opportunities now.
- We also need randomized control trials with measured health outcomes; funding is the main limitation here.
- Making domestic cats vegan meets all of the Effective Altruism criteria: significant, tractable, and neglected.
Main
Imagine you are a surveyor traveling to remote parts of the world. Within a thick rainforest, you come across an indigenous group long separated from the modern world. They fashion spears to hunt fish and thicket baskets to collect foraged berries. Notably, they wear distinctive yellow loincloths dyed with local fruit. You are not one with words, so you call them the Yellowclothea.
This is not a farfetched story. Most species worldwide are classified similarly–someone observes them and then contrives a classification named on what they see. Carnivora was coined in 1821 to describe an Order of animals by the observation that they consumed the meat of other animals–carnem vorāre is Latin for “to eat flesh”.
Let us go back to the Yellowclothea. You can already intuit that these natives do not have to wear the yellow loincloths–it is simply what you initially observed. If the natives swapped the dye with purple or green, that would work out fine. However, the rainforest lacks those colors, so Yellowclothea is resigned to their monotone. In other words, wearing yellow cloth is not a requirement for them to live, just what works for them and is available.
1821, the year of Carnivora’s naming, is ages ago in the scientific world. It was before the Theory of Evolution, first described in The Origin of Species in 1859. It was before the molecular biology revolution. It was before we understood the basis of metabolism and nutrition. So it is easy to confuse classification/observation with the requirement. It is the same fallacy as assuming that the Yellowclothea people can only wear yellow clothing.
Since 1821, we learned more about nutrition, molecular biology, and metabolism to demystify meat. Meat is mostly muscle fibers with some marbled fat and critical nutrients. Carnivora animals generally have more acidic stomachs and shorter gastrointestinal (GI) tracts than nominal herbivores. The extra acid helps chop proteins into the alphabet amino acid molecules, which are readily taken up, so a long GI tract is unnecessary.
So Carnivora animals cannot have salads or raw vegetables, which are rich in fiber and would not break down in their GI tracts in time. Nevertheless, we can make protein-rich and highly digestible foods for Carnivora starting from plant and microbial ingredients. Just as a cow will chemically process the plants into their muscle–flesh, we can similarly turn the plants into food that a carnivore would thrive off without an animal intermediary. In other words, we can source all the required nutrients from elsewhere, without meat.
There is—at least in theory—no reason why diets comprised entirely of plants, minerals, and synthetically-based ingredients (i.e., vegan diets) cannot meet the necessary palatability, bioavailability, and nutritional requirements of cats
Andrew Knight, Director, Centre for Animal Welfare, University of Winchester
I have written about how succeeding meat, dairy, and eggs with plant and microbial-based alternatives will be one of the best things we ever do–I argue that it is better than curing cancer or transitioning fully to renewable energy. Provided that we continue to innovate, we will complete this transition, and we should not just replace the meat that humans eat; we should replace the meat that cats eat too.
Making cats vegan has been contentious, even among vegans. I have read highly upvoted comments on popular vegan forums r/vegan and r/debateavegan “conceding” that cats are carnivores, so we should continue feeding them meat and just advocate veganism to people. This notion is fallacious and relies on a chain of appeals to authority without an eventual biochemical basis. We can render meat unnecessary for cats, and we should absolutely strive toward this reality for all domestic cats.
Cats eat a sizable amount of meat and replacing the quantity is significant. I estimate that we feed domestic cats about 3 billion kilograms of meat per year in the United States. This quantity is about the same amount of meat as the entire population of Canada consumes.1 Replacing even a fraction of meat consumption has a sizeable impact–a study last year estimated that replacing a mere 20% of beef with microbial protein would halve the rate of deforestation. Therefore, replacing a significant fraction of the meat that cats consume would help prevent trees from being cut down. Moreover, getting cats to eat 20% less meat in terms of chicken in the United States would save nearly half a billion chicken a year from brutal livelihood and slaughter.2
Cat food is also linked to human meat consumption. Cat food tends to be the offal of the animal agriculture industry. Producers repurpose meat unfit for humans into cat food. As The Clean Pet Food Revolution highlights, pet food is a vital income stream for the meat industry. Without it, meat prices would go up because margins in the animal agriculture industry are thin. In other words, the less meat that cats eat, the less that humans do too.
In the United States, convenient retail options for vegan cat food are hard to come by. Ami, Evolution, and Benevo are the principal, nutritionally complete brands for vegan cats, but all three are not exactly available in your local Petco. Ami is persistently out of stock. Ami and Benevo are quite expensive–Benevo sells for about $16 per pound on Amazon, roughly four times more than Merrick, a mid-tier meat-based brand.
Vegan cat owners also have more work to do. When a cat is transitioned to a vegan diet, their urine must be monitored for changes in pH. Meat-based food tends to be more acidic than vegan food, which cats are not adapted to. When a cat’s urine is too alkaline, they are prone to forming mineral crystals in their urine, which are painful to eliminate. Owners must acidify their cat’s food as needed. (EDIT: Researcher Andrew Knight brought to my attention that this is not shown to be an increased risk with vegan food fed to cats. Please see here.)
Nonetheless, studies have supported rearing cats on a vegan diet healthily, and we likely have capabilities now to make this more seamless. The solution here is not to wait for cultivated meat–likely still decades away–or even sophisticated alternatives like Impossible Burger. At this point, we need the tofu and soy milk.
Instead, we should get more approved ingredients for cats that enable more formulations. One limitation for approved ingredients in the United States has been testing at The Association of American Feed Control Officials (AAFCO). This non-profit organization serves as a surrogate to the Food and Drug Administration for the guidance of pet food. AAFCO regulates pet food in two key manners: (1) they approve ingredients for retail pet food and (2) set standards for nutritionally complete cat food in terms of macronutrient composition, for example, the minimum amount of protein and vitamins.
More approved ingredients would mean more possible healthy formulations for vegan cat food. AAFCO approval can be laborious and drawn out per discussion with employees at vegan pet food companies.3 That means novel plant or microbial-based ingredients that enable better vegan cat food can take a long time to come to market. Vegan cat food companies are left to concoct recipes with limited ingredients. It is as if you are a chef with only a few ingredients in your kitchen, and you are tasked with making meals with exacting nutritional requirements. You can do it, but your job would be much easier if you had access to protein-rich kōji. If you had more ingredients at your disposal, you could make something more affordable, tastier, and less sensitive to supply chain issues.
Opportunities
I see many opportunities to help realize the vegan cat world sooner than later:
- Funding more ingredients to be tested - More ingredients available for pet food makers would make it easier for them to make better and more varied vegan cat food formulations. Third-party funding on key ingredients would help the entire industry and reduce the entry barrier on retail vegan cat products. Ingredients should be triaged on how many recipes they open up. For example, using the chef analogy, cooking oil would enable more gastronomy than, say, asparagus.
- Develop a more streamlined, expedited ingredient approval process - AAFCO approval process is noted to be slow, laborious, and costly. Ultimately, the FDA and state governments are the ultimate arbiter of pet food and defer authority to AAFCO. Using other organizations, perhaps in other countries, to test pet food would set a precedent for countries with more onerous regulations.
- Funding more formulations for testing - Pet food is a low-margin business. Most pet food is the dregs of the animal agriculture industry, material that would be disposed otherwise. Testing formulations is proportionally more costly compared to testing a new cancer-fighting drug for humans. Third-party funding would offset the costs that are difficult to recoup with sales.
- Funding long-term studies on the health of vegan cats - Currently, most studies on the long-term health of vegan cats are observational or survey-based, meaning that the authors did not design the experimental conditions and rely on post hoc analyses or owner assessment. Ideally, we can do a Randomized Control Trial, the gold standard, on cats with various vegan and non-vegan diets and measure vitals to assess their health outcomes. Funding is dearly needed to perform these studies and would convince the many who are uncertain about feeding their cats vegan. Note that we don’t want just one long-term study. We should fund the study of many different vegan diets to find the best ones, and we should keep funding studies to find better formulations.
- Repudiating what “obligate carnivore” means - Kindly, but stridently, we have to correct folks that obligate carnivore (EDIT) precludes the possibility of a vegan diet. This outdated thinking ignores the fundamental understanding of biochemistry, nutrition, and metabolism, which has only developed since the initial carnivore classification.
- Advocating to vets - On a similar note, we need to evolve vet’s outdated nutritional understanding of carnivores and appeal to their better nature about helping all animals, not just companion ones. Vets are positioned well to understand the health of cats and to ensure that the owner is rearing vegan cats as well as possible.
- Rearing vegan cats - There is enough evidence that cats can be raised vegan healthily. Since raising cats vegan continues to be pilloried and dismissed, there is an opportunity to do good here by being a leader and an example for others. Be that owner who raises their cat vegan. I have previously argued that pioneers at the start of an S-curve transition do inordinate good by “shifting the curve.”
Responding to Common Concerns
I’ve heard plenty of push back on some of the ideas, so let me respond:
- “These diets are not natural” - The (EDIT) appeal to nature argument is wrong, outdated, and destructive. So much so that I wrote the entire first chapter of After Meat explaining why–you can read or listen to it for free here. Furthermore, the meat-based cat food on the market differs from what cats “naturally” eat. Store-bought meat is what’s unsuitable for human consumption–the scrap animal parts: livers, stomachs, etc. This meat is far from the fresh flesh that cats eat during wild hunting.
- “These foods would be too synthetic, too processed” - Cat food already on the market is highly “synthetic”. Because store-bought cat food meat is often so diseased, it usually has to be boiled for sterilization. The poor quality meat and sterilization depletes vital nutrients such as taurine, zinc, thymine, vitamin E, vitamin A, vitamin K, copper, manganese, vitamin B12, folic acid, potassium, vitamin D, and others. These nutrients often must be supplemented back in. Secondly, I argued why “processed” is an imprecise, unhelpful adjective when discussing food. Long story short, calling a food processed will not tell us if it is healthy or unhealthy.
Conclusion
In After Meat, I concluded we would have plant and microbial-based alternatives better than conventional animal products regarding taste, cost, and nutrition. Relying on animal technology has physical limits. It’s not just winning on ethics and the environment; alternatives can also exceed on purely selfish consumer values. In the same way, we can eventually do the same with cat food and reach a win-win.
Enabling more vegan options for cats is different from animal product alternatives for humans or dogs. First, there’s addressing the confusion about whether we can rear cats in a healthy vegan manner–we can, and funding more studies will show this demonstrably. The second issue is fostering market conditions for more vegan cat food options. The limit is regulatory, and third-party funding is sorely needed to get more ingredients tested and to defray development and approval costs for vegan pet food producers.
Notes
1 There are about 60 million cats in the United States. The average cat is about 10 pounds and requires about 300 calories per day. It’s hard to get a figure on the percentage of meat in store bought cat food, but I estimate around 75%, so that translates to 225 calories from meat. There’s roughly 200 calories per 110 grams of meat. So each cat consumed roughly 125 grams of meat per day. For all the United States, that’s about 2.7 billion kilograms of meat per year for all the cats. Canada consumes about 85 kilograms per person per year * 37.5 million people = 3.1 billion kilograms of meat per year.
2One chicken is roughly 1 kilogram of meat. 20% of 2.7 billion kilograms is 0.54 billion kilograms, so that’s roughly half a billion chickens.
3I discussed with employees at Wild Earth and v-dog.
Could you provide a source for this? In biology, "obligate carnivore" means "obligate meat eater". They cannot get sufficient nutrition from plants alone. This doesn't rule out an artificial diet providing the missing nutrients, or someone incorrectly classifying a non-obligate carnivore as obligate due to bad data. But it does not mean "based on observation". Your description holds for the order carnivora, but that is not synonymous with carnivore because biology as a field is dumb.
In your Opportunities section you suggest doing more rigorous RCTs on vegan cat diets (which I agree with), but the rest of your post feels like you considered the question settled. You link to sources claiming that result, but it feels like an aside rather than your focus. I wish you had gone into these in detail, because the papers look quite bad to me.
The main website you link to links to a review article in which only 4 studies with a combined 39 subjects use blood tests rather than owner reports, and more than half of those were given vegetarian diets, not vegan (even though the table header says vegan). The only RCT didn't compare with carnivorous diets. This is already not nearly enough to consider the question settled, even if the studies strongly supported no-meat diets.
But also I can't find where this paper actually reports results for cats in an organized way? There are tables for dogs, but for cats there are only text descriptions. These mentions multiple problems, albeit one of them preventable. And again, these cats were mostly on vegetarian diets, not vegan (and not necessarily for very long, although 2 weeks was long enough to develop problems)
It very much looks like the authors of this review article wanted to say no-meat diets were harmless for cats, but the data went so strongly against their point they couldn't manage it.
I'm confused why the study both says this as you've highlighted, but then in the discussion and conclusion it says:
Except, as you pointed out, convincing evidence of major adverse effects resulting from feeding cats vegan diets appear to have actually been observed as stated by the same authors saying it has not been observed. I notice I am confused given I do not think the paper is authored by bad actors.
Part I want to highlight in image below: Cats were supplemented. So the adverse affects you highlighted it sounds like you could prevent with supplements. Is this the only reason the authors conclude cats can be fed a vegan diet? But then it sounds like a better and more responsible conclusion by the authors would have been: it seems theoretically possible that a vegan cat food could exist with correct supplementation, but no healthy vegan diet for cats exists yet (all studies show specific supplementation thus far is neccesarry for existing vegan foods otherwise your cats might very quickly develop major adverse health outcomes - am I wrong?).
They also highlight they didn't review the suitability of the supplements? What does this mean - "suitability"? Cant find an answer for that.
I could have the official definition wrong--I edited the post. I'm thinking about it colloquially and repudiating how it's conceived for example here.
I agree that the paper you highlighted is not making its case strong nor clear.
The best evidence seems to be survey based; for example, here: https://faunalytics.org/plant-based-cats-are-healthier-according-to-guardians/
Andrew Knight, a foremost researcher in the area, has a more definitive study publishing this year.
Otherwise, yes, I agree that we must continue to work our way up the Hierarchy of Evidence and campaign for more and better "formal" science.
This is not a semantic issue you can fix with a minor edit. Your post rests on the assertion that cats can be healthy when fed an exclusively plant-based diet, and that these diets are already available. You are sure enough of this to say we should "stridently correct" people who believe they can't.
You can claim people are wrong to categorize cats as obligate carnivores, but you need to demonstrate that with evidence, which you absolutely have not done. You say the best evidence is survey based, but with such a motivated population and minimal reporting I consider it meaningless.
Even in this comment you act as if the linked reddit comment (copied below) is obviously false, but it is using obligate carnivore correctly and you have provided minimal evidence to even suggest reconsidering that designation.
My steel man here is that it might be possible to render cats vegan with new technology, and you think it's worth doing. I don't necessarily disagree with that, but it is such a different claim than "cats are not obligate carnivores and can all happily live on a vegan diet today".
Reddit comment Karthik links to:
> Hello there. Pet nutritionist here, trust me when I say cats ARE obligate carnivores. If you feed them a vegan diet they WILL die slowly and painfully, no ifs ands or buts. If you cannot cope with the idea of your cat eating what it needs to in order to survive. Give it up
The argument isn't solely based on the survey data. It's supported by fundamentals of biochemistry, metabolism, and digestion too. I won't presume to know your biology knowledge. Earlier, you said "biology as a field is dumb", which may or may not be indicative of much personal study of biology. So I apologize if this is over-explaining, but I feel that I may have glossed over it when making the post:
Mammals such as cats will digest food matter into constituent molecules. Those molecules are chemically converted to other molecules--collectively, metabolism--, and energy and biomass (muscles, bones) are built from those precursors. For cats to truly be obligate carnivores, there would have to be something exceptional about meat: (A) There would have to be essential molecules--nutrients--that cannot be sourced anywhere else OR (B) the meat would have to be digestible in a way that's not possible with plant matter.
(A) is very easy to correct for. Just test formulations for missing nutrients (molecules) and add them. So far, there are no "special" meat molecules that can't be sourced from elsewhere. (B) is making a more digestible formulation. If we extract pea protein and measure the digestibility, we'll know if it'll work for a cat or not.
On (A), AAFCO is setting this already with their nutritional guidelines, e.g. minimum amount of proteins, vitamins, etc. On (B), part of the ingredient testing is making sure the food is digestible for cats (also testing for toxicity).
So any plant-based food that passes AAFCO guidelines is nutritionally complete for cats. Ami does, for example.
One of my points is that people's assumptions about carnivory fail to consider biochemistry. Yes, the formal scientific studies are lacking, but it really shouldn't matter based on what's known about more fundamental biology. Do we need long term studies to absolutely know that Yellowclothea people are safe to wear purple?
I agree that more formal studies higher on hierarchy of evidence would convince folks, seemingly like yourself. And to that point, I advocate for more of it. But given what I've researched and what I know about biology, I would feel comfortable raising a cat vegan healthily and recommending others to do the same.
I have a BA in biology. "Biology is dumb" was an attempt to be cute about the inherent messiness of living organisms and attempts to classify them.
You say you've done research satisfying you that this is all biochemistry and we know everything we need. Can you write that up? How are we sure we've identified every useful nutrient? How do we know the bioavailability tests are any good? Without that this is still just an asserton, and a fairly surprising one given the state of human nutrition.
To be clear, this is not what I'm arguing. Biochemistry research is never complete. I'm arguing that it's safe to feed cats vegan based on what's known.
Here's the AAFCO list of required nutrients for cats and what I view as authoritative (pages 13-14):
https://www.aafco.org/wp-content/uploads/2023/01/Model_Bills_and_Regulations_Agenda_Midyear_2015_Final_Attachment_A.__Proposed_revisions_to_AAFCO_Nutrient_Profiles_PFC_Final_070214.pdf
I'm not sure. But these questions persist for Fancy Feast and any other meat cat food as much as they apply to vegan cat food. Are we sure they have every useful nutrient and that the measured bioavailability is good?
Okay, it sounds like your argument is "vegan cat food is capable of meeting the same standard as meat-based food".
From skimming the AAFCO document it's not obvious to me AAFCO thinks meeting its standard is sufficient for health (see screenshot below, from page 2). Perhaps there is something I missed, but I have put a lot of time into reading papers I found shoddy and you didn't find worth defending, so I would like to be sure this why you believe what you believe before investing more time checking it out.
Indeed.
As you pointed out earlier, we don't know everything that we could know. What do you propose we do? It sounds like your concerns are with food testing for cats period, and they're not specific to the vegan formulations.
My stance is that if it's okay to feed cats meat-based food, then it's fine to feed them vegan food.
Feed animals close to their natural diet while researching how to do better. You dismiss this as "appeal to nature", but I would describe it as "the burden is on the attempt to change the default".
> It sounds like your concerns are with food testing for cats period
I assure you I am at least as obnoxious about human nutrition testing, which is better studied and features a more adaptable subject.
"Meeting nutritional requirements" is a far better default standard than what's "natural". Few problems with the "natural" standard:
Yep, human nutrition is better studied. There's more funding and more interest in the subject.
As discussed before, we're both in agreement for more studies. Funding is needed.
I think when she said "natural diet" she didn't mean to invoke the naturalistic fallacy.
She meant the diet that we have the most empirical evidence doesn't harm/kill them. We have some empirical evidence that vegan diets appear to quckly give cats major bad health outcomes without supplementation? The first comment in this thread by Elizabeth pointed this out.
We don't have empirical evidence of the same happening with meat-based diets. So modern nutritionally complete meat-based diets presently have a 100%-wont-cause-major-adverse-health-outcomes rate. Is this not what the studies seem to show?
No, but consider statistical averages rather than semantic absolutes. If you were to consider all possible meals a cat could reaonably be fed today. On average, it seems reasonable to suspect that they would be healthier if more of those meals were meat-based than plant-based. This is an empirical question, not a semantic one. The nutritionally-complete vegan cat food might be better than the diseased corpose (one single comparison). But having nothing but the nutritionally-complete vegan cat food might be far worse than nothing but meat (statistical average across many samples).
Given how nascent the field is and how we're only just finding out what supplementation we might have to give cats, it seems like if we were to tell everyone to feed their cat vegan food that we'd probably get a lot of cats with bad health outcomes.
And this would be pretty bad optics-wise for the vegan movement.
Do we have empirical evidence that a specific meat-based food is consistently safe over many years? My understanding is that many change constantly.
Not really. Check out the recall withdrawals over the year: https://www.fda.gov/animal-veterinary/safety-health/recalls-withdrawals
Best we can do is what AAFCO and FDA already do. AAFCO sets nutritional guidelines and ingredient requirements. FDA regulates the safety.
Why is that diet representative of for example nutritionally complete Ami, which has been around for years? Isn't it much better to just defer to AAFCO's and FDA's standards, which Ami meets?
The most parsimonious explanation is that the lack of supplements was the problem, not the "vegan"-ness. If I get sick from my potato chip diet, it doesn't mean I should avoid a plant-based diet with all required nutrients.
Based on what? I don't intuit this at all. Furthermore, we're not saying any plant ingredients. We're saying the ones that meet nutritional, toxicity, and digestibility requirements for cats.
Both you and Elizabeth have offered something fairly distinct from AAFCO's/FDA's standards. And so far, I'm finding neither to be better.
It's not nascent. AAFCO has been providing guidance on the nutritional requirements for cats for decades.
For me: I agreed with you and felt like my mind was being changed to being pro-vegan-cat - until I read Elizabeth's comment pointed out the issues in the study. So for me it is mostly because you haven't engaged with that specific comment and pointed out why the concerns that are highlighted in her screenshots (from the actual study!) are not something that I need to worry about.
Convince Elizabeth and you, by proxy, convince me I'm pretty sure.
Sounds reasonable to me. I didn't say that a lack of supplementation wouldn't solve it. I argued that meat would. Arguing for X doesn't mean I argued for ~Y.
The study came out January of this year. That's pretty recent.
Does a nutritionally complete vegan cat food exist yet that takes everything learnt from this study and all the studies it references into account without need for additional supplementation? If yes, I'd want to see a study where cats are fed it first before I place my own cats exclusively on it. Till then I'd probably be too paranoid to feed them a fully vegan diet.
I'm confused. By "that diet" you mean to say the diet that was tested in the actual study you use as support for your claims should not be taken as an example of something nutritionally complete?
Ok, after trying to figure out what "Ami" was I see in your post you refer to it as vegan cat food that exists on the market.
Apparently it has also been around for 20 years after a quick Google search. Now I'm just hyper-confused why Ami wasn't used in the Domínguez-Oliva et al. Study instead.
Thanks Cornelis, I sincerely appreciate the good will shown.
I conceded on Domínguez-Oliva et al., and Elizabeth's concerns were entirely valid. However, it's one study and one diet, and I felt that Elizabeth was ignoring the basis of nutrition and biochemistry that I emphasized throughout the post. Thanks for highlighting that the food was lacking necessary, known supplements. That was a key point that would have been helpful to broach earlier.
A RCT study will likely be just a formality for something like the Ami vegan cat food. And yes, it's frustrating that this hasn't been done/published yet! As I understand from Andrew Knight, there's a better study coming out this year.
I haven't found Elizabeth willing to falsify their thinking as much as you and perceive general antagonism and defensiveness.
Nutrition is hella complicated. As someone who drinks a ton of Soylent, I am often surprised by how my own view of "it shouldn't matter as long as the molecules - when you break it down - are the same" is overly simplistic. If you have food substance A and food substance B and their molecules are organized differently, then even if you were to break them down and get the same base nutrients, this does not mean they are equally healthy for you. This is because their different initial arrangement can lead to different biochemical cascades. I recently learnt that antimicrobial mouthwash might influence your mouth bacteria to such a degree that is leads to a decrease in NO production to the point that your blood veins don't dilate as much = causally linked to increased arteriosclerosis. There is an entire scientific journal just dedicated to this pathway. See here.
I would never have intuitively thought this could happen. I can increase my risk of heart disease by nuking the bacteria in my mouth? Lol... wat?
It really is not a stretch to imagine that even if meat and vegan food appears to be nutritionally complete and - if broken down -they yield similar macronutrients - that still because the vegan food has a different composition before being broken down that different biochemical pathways are kicked off leading to harm that the meat-based one does not lead to. Something weird and unexpected like the NO pathway could explain why cats on vegan diets still get health issues as the pro-vegan study Elizabeth linked to shows.
An escape hatch from this would of course be lab grown meat that is to the molecule identical to meat. In that case it wouldn't make sense for one to be any different from the other because they are not only to the molecule identical, but also to the molecules are arranged the same way before being broken down.
So my read is you haven't considered option C: There could be an essential arrangement of molecules in meat before they are broken down, that currently cannot be sourced elsewhere (not until we get lab grown meat anyway).
But we have the same uncertainty with retail meat-based cat food, which I've highlighted is quite distinct from what cats evolved on.
I don't understand the obeisance to molecularly-exact meat. Evolution doesn't select for health and well being. It selects for propagation for a specific niche in a specific environment. Our goals with domestic cats are different than what evolution optimized for.
Consider human evolution. For most of it, life expectancy was far lower than today. The diet of prehistoric times isn't by default aspirational. Instead, current nutrition studies focus on health outcomes, e.g. life expectancy, blood pressure, rate of obesity, etc.
So recommendations focus directly on cause (food eaten) and effect (health outcomes). And that's what we should do with cats. We should not put meat on a pedestal and beeline for that.
Actually, I think we don't have the same uncertainty. Those products have been iterated on for a far longer time than vegan cat food - including multiple FDA recalls as you pointed out. We've had much more of a "trial-by-fire" of retail meat-based cat food over a longer period of time.
Though in the other comment you pointed out Ami, which given it has existed for 20 years, I imagine has gone through the same trial-by-fire. A new post that does nothing but focus on the evidence that Ami is fine for your cat would probably convince a ton more people. As I mentioned in my other comment I'm very confused why Ami wasn't used in the Domínguez-Oliva et al. Study instead.
I'm not interested in molecularly-exact meat. I'm interested in what - via strong empirical evidence - we know wont harm my cat.
Couldn't agree more, which is why, if we get enough empirical evidence that some particular vegan meal will be ay-ok for cats I'm all aboard.
It is worth adding that I do think we have enough empirical evidence to place dogs on a vegan diet without issue. But my read of the study is we're not there with cats yet. I really don't understand why the study authors make the same conclusion for both cats and dogs. The evidence appears to clearly be vastly stronger for dogs than it is for cats.
We should put empirical evidence on a pedestal and while truth-seeking be neutral about whether that includes or excludes meat.
Thanks Cornelis, I agree about the empirical evidence. And indeed, emphasizing Ami and how long it's been around would have obviated a lot of confusion here.
We seem to disagree about (1) the variance of meat-based retail products versus vegan ones and (2) whether or not the "trial-by-fire" standard is more helpful than just simply the criteria that AAFCO/FDA defines regarding nutritional, toxicity, digestibility, and safety.
(1) Sounds like your priors for the intra-variance of meat-based cat food are lower than the inter-variance between validated meat and vegan cat food. I don't share these same priors, and the best I can offer is Chapter 6 of After Meat where I explain in detail how I think about nutrition including the fungibility of food. Long story short, I really don't think there's anything special nutritionally about meat that can't be recapitulated elsewhere, but I understand that not everyone has that intuition.
(2) AAFCO updates their standards in light of new evidence. The "trial-by-fire" is baked into their standards. And I suspect if we had similar priors regarding (1), this point may be moot.
But I appreciate your good faith, and I'll leave it here.