This is a transcript of the Gastropod episode A Dog’s Dinner: What Should We Really Be Feeding Our Pets?, first released on May 19, 2026. It is provided as a courtesy and may contain errors.

CLAUDIA GEIB: So it is just about seven o’clock, which means that Oona is starting to give me some looks as if she’s never been fed before. …Hey, Oona. Do you want to have dinner?

[TAG JINGLING, FAINT BUMP]

GEIB: [LAUGH] That was her nose hitting the microphone.

CYNTHIA GRABER: If there’s one topic we’ve heard many requests for over the years, it is for a pet food episode. It’s probably our most requested episode.

NICOLA TWILLEY: You, dear listeners, have been looking at us with those big sad eyes and wagging your tails—honestly, pretty much begging us for it, and we just can’t deny you any longer. We, of course, are Gastropod, the podcast that looks at food through the lens of science and history. And I am Nicola Twilley.

GRABER: I’m Cynthia Graber, and our producer is Claudia Geib and her dog is named Oona.

GEIB: Okay. So Oona eats Purina Pro Plan, performance, 30/ 20. Chicken and rice.

[BAG CRINKLING, SCOOPING INTO BOWL]

GEIB: And because she is a Gastropod dog, she gets some of the vegetables left from whatever we’ve made for dinner. So tonight she gets some cauliflower and some kale stems.

[CHOPPING, SCRAPING INTO BOWL]

TWILLEY: Yum. Or at least, that’s what Oona is thinking.

GEIB: Okay. Sit. Down. Up! Little song and dance. Wait. Wait! I’ve got to put the microphone by it.

[ENTHUSIASTIC DOG EATING NOISES]

GRABER: Dinner served! That is one happy dog. But pets have been around a lot longer than we’ve had packaged food, so what did we feed them in the past? Has it always been some version of that dried kibble?

TWILLEY: And what is really in those dried brownish shapes? Is it good for your pet or should you be feeding them chef-crafted meals instead?

GRABER: When it comes to our own food, some of us try to take into account not just how healthy it is, but also what the environmental impacts are. So what about pet foods? Are any options better environmentally than others, and at the end of the day, does it matter? Would changing what you feed your pet even make a difference?

TWILLEY: Join us at the kibble buffet this episode for the behind-the-scenes story of pet food. This episode is supported in part by the Alfred P. Sloan Foundation for the Public Understanding of Science Technology and Economics. Gastropod is part of the Vox Media Podcast Network in partnership with Eater.

GRABER: We know you’re jumping up and down excitedly because you’ve been begging for a pet food episode for years, but first: we haven’t mentioned this in a while, but we wanted to remind all you listeners that while give you Gastropod for free, it most definitely isn’t free to make.

TWILLEY: To be able to make the show, we rely on three main pillars of support: foundation grants, revenue from advertising—which is way way down right now—and donations from generous listeners like you.

GRABER: Generous can mean at absolutely any level! If you can give a dollar an episode or the equivalent in a one-time donation, like 25 bucks, that’s great. If you can give more, that’s fantastic. We have lots of fun listener perks, like stickers, and special supporters’ newsletters, and even birthday shoutouts on the show.

TWILLEY: So get on board the Gastropod train and do your bit to help keep the show going at gastropod.com/support!

[MUSIC]

RACHEL KELLY: Around 50, just over 50 percent of US households own a pet. And dog ownership has kinda steadily increased over the years.

GRABER: Rachel Kelly has researched both what we’ve fed dogs historically and what we feed dogs today. More than half of all the pets in America are dogs.

TWILLEY: In fact, there are more than twice as many dogs living in America as there are people living in California. Globally, there are so many pet dogs that if you weighed them all, they’d weigh more than all the other wild mammals left on earth. Which is a lot of dog!

GRABER: In America, there are also a lot of cats, more dogs than cats, sure, but almost half of all pets in the US are cats. The two together, cats and dogs, they make up nearly all pets. And we collectively spend a lot of money to feed them.

MICHAEL COREN: It’s become a $66 billion market in the United States, and 140 billion globally.

TWILLEY: Michael Coren is a columnist at The Washington Post. And it is true, the world of pet food is vast and varied.

KELLY: You know, there’s dry foods, dry kibbles. Um. All an assortment of, of those for different life stages. Be from puppy to adult to senior. Wet food, canned food, dehydrated foods. You have fresh foods, which is a big growing market.

GRABER: You can wander down entire aisles in the grocery store just shopping for your pet, you can go to a big box store that sells practically nothing but pet food, you can order home delivery of specially crafted meals—but, of course, this wasn’t always the case.

TWILLEY: Dogs and cats have been our constant companions for much longer than we’ve had kibble. Cats began hanging out with humans shortly after we started doing the whole agriculture thing, which led to grain storage, which attracted rodents.

COREN: Cats are sort of like, work together with us. So they decided to eat a lot of mice in our graineries. And when it’s convenient, they like to hang out with us. And when it’s not, they—they’re outta there. And in fact they’ve never been domesticated which I think a lot of cat owners probably realize. So they are at best, maybe cohabitators.

TWILLEY: All cats are descended from something called the Near Eastern Wildcat, which is still around today, and which looks exactly like a cat! They’re so indistinguishable that scientists studying populations of wildcats can’t tell which cats are actually wild and which are just feral escapees.

GRABER: Dogs are a different story—we did actually domesticate them from their wild relatives, wolves. Wolves started nosing around campsites even before the dawn of agriculture, enjoying what food they might be able to forage from our garbage. And over time the relationship they had with us transformed them.

COREN: What I understand about the genetic distinction between wolves and dogs is that dogs have evolved the ability to eat a lot of different foods that are not just carnivorous, compared to their wild ancestors. And they’re also able to recognize human emotions and expressions, and they just relate differently to us. That’s a clear sign that over time, their genetic- their DNA has kind of adapted to hu- the human environment as much as the wild one.

TWILLEY: Today, dogs are an entirely different species from their wolf ancestors, but no one can pinpoint exactly when that transition happened.

EMILY ANTHES: There’s deep disagreement about, you know, was it just over 15,000 years ago that dogs emerged? Was it 30,000 years ago? There’s a big debate about that.

GRABER: Emily Anthes is a science reporter at the New York Times, and she has a column there called Pet Theory. She says, when it comes to figuring out exactly when dogs diverged from wolves, scientists can use a couple of different types of evidence.

ANTHES: So one is archeological specimens. So we can and do dig up, you know, skeletons, animal remains from archeological sites. And archeologists sometimes say, like, oh, hey, that looks more like a dog to me than a wolf. But you can imagine, especially in the very early years of dog domestication, dogs and wolves probably didn’t look that different. So it’s hard for archeologists to tell. So the more definitive method has been considered looking at, and analyzing, DNA. The problem is DNA, that old also degrades and is hard to piece together.

TWILLEY: The oldest piece of DNA from a domesticated dog came from about 10,000 years ago. Until just this March, when an exciting new paper came out. Emily spoke to the scientists who made the discovery—they had found much older genetic evidence for a dog.

ANTHES: This was a dog that probably lived about 15,800 years ago in what is now Turkey. They looked at the DNA and said, yes, that’s definitely a dog. So it’s a big deal because it pushes the genetic evidence of dogs back by 5,000 years.

GRABER: In a way, that’s not super surprising. Like Emily said, many scientists had thought that we’d domesticated dogs at least 15,000 years ago, and maybe even further back, we just didn’t have definitive evidence. But what’s even more interesting about the new research is that it helped scientists take a second look at other skeletons and DNA that had already been found at ancient sites, but it hadn’t been clear whether they were wolves or dogs.

TWILLEY: That’s because they only had little bits of the DNA from these other sites, not enough to be sure. But these little bits were exact matches for the pretty complete DNA from this new find. And that means we can say that these other finds are indeed dogs after all.

ANTHES: At the end of this process, they had identified five paleolithic dogs, so these were dogs from back when humans were still hunter-gatherers, that came from sites across Europe. So they ranged from the UK to Turkey, and you know, some in central Europe in between.

TWILLEY: So now we know that not only were there dogs fifteen thousand years ago, but those dogs were also relatively widespread.

ANTHES: And they were widespread enough that they seemed to be living alongside several different hunter-gatherer societies. So it wasn’t a case of sort of one society had happened upon the dog, and it was just at the birth of this thing. It means that the actual first dogs must have been much earlier than that, and that by this time, sort of multiple human societies had—had discovered dogs.

GRABER: So dogs have been dogs for a really long time, way before humans started farming. But what’s also fascinating is that the dogs in these communities were pretty similar genetically, but the humans were actually pretty distinct. So scientists believe, maybe one group of people domesticated wolves into dogs and passed them along, and the dogs were so useful that everyone kept trading them around.

ANTHES: But these societies lived in very different environments. They had different cultures, different tools, different languages.

TWILLEY: And so they would likely have had different uses for these new dog friends, some might have used them for help hunting, some might have used them to haul things, some might have used them to guard against predators.

ANTHES: A metaphor one of the scientists used that I loved was, you know, maybe these dogs were like Swiss army knives that were pretty good at doing a lot of different things.

TWILLEY: We’re used to thinking of dogs as being bred to specialize at different tasks, like a border collie for herding, or a terrier for hunting rats, but that’s a very recent development in dog history. These first dogs seem to have been multi-talented.

GRABER: Those useful dogs did have to be paid for all that usefulness. And not just in belly rubs, but of course in food. It turns out that the scientists were able to figure out kind of generally what the dogs were eating—not like three pounds of moose liver per day or anything that specific, but they could figure out their general diet.

ANTHES: In the British site, what they were able to tell was that the diets of the humans and the dogs were similar. Which maybe raised the possibility that humans were, were giving food to the dogs.

TWILLEY: In Turkey, the data from the dog bones showed that the dogs had actually been eating quite a lot of fish.

ANTHES: And fish are something that these dogs probably would not have been able to get on their own. You know, there are occasionally reports of, you know, dogs going out and, and catching live fish. But in general, this isn’t something dogs do. So sort of the conclusion there, that they tentatively make, is that if the dogs were eating fish, it was probably because humans were giving them fish. Or providing them in some, in some way, whether it was giving them to the dog or throwing the scraps on the ground.

GRABER: And so at this point in history, 15,000 years ago, dogs were definitely dogs, they weren’t wolves and probably hadn’t been for a while, and also, they were likely eating the scraps from our tables, they were eating human food.

COREN: They would eat whatever was left over. They would steal what they could which is still, you know, a modus opera operandi for a lot of them, including mine.

TWILLEY: Of course, these scraps would have been quite different from what you might have in your compost today. Historically, households would be wrangling very different pieces of meat than a chicken breast or a burger patty—they would be boiling calves feet, and deboning pig heads, and all of that generates a fair amount of scrap.

GRABER: Same with the grains and vegetables, a lot of the processing was going on at home, and so there would have been a lot of non meat scraps as well that dogs would have enjoyed.

TWILLEY: For millennia, this is how dogs ate. Rachel told us that this all started to change around the time that human food was also going through a big change, when Britain started to industrialize and urbanize.

KELLY: So the commercial dog food industry originated in Great Britain in, around in the late 1700s.

GRABER: London was already a huge city at the time, it was well on its way to becoming the largest city the world had ever seen. It was full of people living close together. The streets were teeming with horses to help all those people get out of town or from one part of town to another.

TWILLEY: And when those horses got old and tired or sick and injured, they made perfect pet food. London was famous for street vendors selling boiled horsemeat on skewers—they were known as Cat Meat Men and they would call out as they roamed the streets looking for customers.

GRABER: There were thousands of these Cat Meat Men all over the city, and they sold horsemeat not just for cats, but for dogs, too. This was really convenient at a time when a lot of people were living in really close quarters and they didn’t necessarily do all the meat processing at home. Those jobs were getting outsourced.

TWILLEY: For a lot of folks in the city, that was the meat part of dog food sorted. For the grain part—well, at the same time the horsemeat trade was taking off, people who made biscuits for humans started making them for dogs, too.

COREN: And it was based on ship’s biscuits. So this is the food that you would, you know, feed to sailors. It was never very good, but it was cheap and plentiful.

GRABER: A few decades later, as we get to the 1800s, dogs had become even more important in England. They were being bred and specialized into, say, hunting dogs, or racing dogs, also inside lap dogs. Brits held the first dog shows. Many of the dog breeds we know today emerged at this time, not all that long ago.

KELLY: And the dog’s role kind of began to slowly shift to more of one asa family member as opposed to this distinct animal entity who lived outside and, you know, did whatever dogs do outside.They more transitioned to live into the home, with people.

TWILLEY: The first commercial dog biscuits seem to have been aimed at some of the more valuable hunting and racing dogs: greyhounds, and fox terriers, and pointers that gentlemen would take along with them on shooting weekends. Various different brands of biscuit were advertised in sporting magazines, with testimonials from the owners of prize-winning dogs.

GRABER: The most famous brand, and the one that started the whole commercial dog food movement in the US, was called Spratt’s.

KELLY: There was a, a person called James Spratt, and he was actually an American who was living in Britain. But moved to the US like the 1870s or so. And he had these biscuits that he advertised as nutritionally enhanced biscuits, and they were kind of marketed for hunting dogs or purebred dogs to kind of improve their performance in the field or in the show ring.

TWILLEY: Spratt’s most famous product was his Celebrated Patent Meat “Fibrine” Dog Cakes, which apparently included beets. These were large, square, very fiber-filled biscuits, and dog owners would add water and break them up to feed to their dogs, typically alongside meat scraps.

GRABER: But still at the time this was a really small market. Most pet owners were still feeding their pets entirely on kitchen waste and leftovers. So how did we get from dogs and cats just eating what was around, to entire meals specially crafted for their shiny coats and their gourmet delight? That story, after the break.

[BREAK]

TWILLEY: In the pet food world, food is divided into two major categories: wet and dry. Dry is kibble. Wet—which is truly an unfortunate term to apply to food but never mind—wet just means canned.

GRABER: As we’ve reported many times on the show before, canning was invented in the early 1800s, the can opener was invented in the 1850s, but canning didn’t start to become more common until the end of the 1800s, beginning of the 1900s. It was still a pretty expensive technology.

TWILLEY: The first canned pet food was introduced in 1916, and like the food sold for pets on the streets of London, it was mostly horsemeat. The biggest brand was called Ken-L Ration, and it was produced by a company that started out supplying horses to the US military during World War I.

GRABER: Those were horses for people to ride, not of course for pets to eat. But a couple of things happened. The war ended, and more importantly, cars were replacing horses on city streets. This started in, like, the early 19-teens, and horses kept losing to cars throughout the 20s. So, well, there was a ready supply of meat from a retired form of transportation.

TWILLEY: Street scraps rather than table scraps.

GRABER: And then World War II came along, and again, we’ve covered this on the show about a zillion times, but after the war, almost everything changed in the world of agriculture and food.

KELLY: You had the industrialization of agriculture. We saw an increase in the consumption of processed foods. Those became a lot more mainstream and affordable. And you had more women kind of entering the workforce as well, after the war. And having less time to be at home cooking for families. So there were kind of these socioeconomic changes happening. And then you kind of had a post-war economic boom.

TWILLEY: All of that added together meant it began to make more and more sense to buy ready-made dog food at the store, alongside your boil in bag peas and TV dinners. It was convenient, it was affordable, and it was also heavily advertised.

GRABER: Because it was still more convenient and cheaper to scrape off your plate into the dog’s bowl. In the early 1960s, the National Pet Association’s manufacturer’s committee even said their biggest competitor was table scraps. People weren’t buying much pet food at the store.

TWILLEY: And so pet food manufacturers began a campaign to change that. The first job was to convince Americans that doing what they’d always done and feeding their dogs scraps was practically animal abuse.

KELLY: More and more people considered their dogs family members. So why would you feed your family members scraps?

GRABER: And they hired vets to be the voices of reason, the ones to tell Americans that it was the pet food manufacturers who knew what to feed your beloved dog or cat, you should trust them. That was the message in the ads.

KELLY: Pet food manufacturers and veterinarians kind of filled that role of being an expert of canine nutrition. Whereas like your average pet owner couldn’t really necessarily do that, reliably.

TWILLEY: What was sort of underhanded about this message was that in the 1950s and 60s, commercial dog food was still pretty much scraps—it was just industrial scraps rather than table scraps.

GRABER: And even though people appreciated the convenience of packaged pet food, they also started to get concerned about what might end up in the final product. This concern was justified at the time: the labels weren’t always accurate. Horse meat was sometimes labeled beef, diseased animals that were culled sometimes ended up in pet food.

TWILLEY: These kinds of shenanigans had also happened in human food, and the resulting outrage had led the government to set up the FDA. Something similar happened with pet food: a nonprofit organization called the American Association of Feed Control Officials, or AAFCO, which was basically a forum for state level officials to establish shared standards for livestock feed—they set up a pet food committee in the 1950s.

GRABER: And by the end of the 1960s, they created pet food standards. Everything that was on the label had to be accurate—I know, shocking. And like human food, it had to be listed in the order of which ingredients there was the most of. And then on top of that, they copied what the government was doing with RDAs and the food pyramid for humans and they developed the standards for meals that would keep pets healthy.

COREN: And that’s called the complete and balanced criteria. So basically, if you buy an AAFCO commercial, complete and balanced food, you’re getting the same thing, more or less wherever you are. And that has you know, a set minimum and maximum for different nutrients. There’s been some feeding trial protocols for dogs and cats. And then manufacturers have the right to then put “complete and balanced” if they’ve met those criteria.

TWILLEY: So basically, with the introduction of these standards, it meant that the pet food companies could develop recipes that combined ingredients in a way that met the AAFCO nutrient profile, that pets wanted to eat, that humans wanted to buy, and that made them a profit. And that’s how we get today’s pet food.

GRABER: Pet food today contains a bunch of different ingredients. What will probably not surprise most of you who have pets is that nearly half of it is some form of meat.

KELLY: So it’s, it’s really across the board. I would say most—most of the foods you find at your store will be like chicken, turkey, beef, fish, but. A lot of those are meat. Meat and or meat byproducts.

TWILLEY: Meat meat, for people, means things like chicken breast or pork chop. In pet food though, the AAFCO definition of meat also means the slurry of leftover meat, fat, and bone chips you get after mechanically deboning a carcass. That sounds like a byproduct, but actually, under AAFCO rules, that counts as meat. A meat byproduct is something else.

GRABER: These are other parts of animals: things like lungs, brain, bone, stomachs, cleaned-out intestines. These are just some of the animal byproducts that are allowed in pet food.

KELLY: I mean, you have people who would be grossed out by the idea of dogs eating, like, hooves, for instance, or, or chicken feathers or whatever else they use in meat byproducts. And then,my own dogs will try and snatch up, you know, [LAUGH] gross things that we find on our walk. So dogs certainly have a different different taste for, for different things.

TWILLEY: Meat and meat by products make up just under half of the typical pet food recipe. The rest is mostly some form of grain.

KELLY: Probably rice and corn being the two biggest ones.

GRABER: But no matter what animal’s meat is being used, which part of the animal, which grain the pet food includes—if it has an AAFCO label for their standard pet food, called complete and balanced, it is literally all the same nutritionally. Unless your vet tells you your pet has a particular health issue, your pet will get everything they need even if they eat the exact same thing for every meal.

TWILLEY: AAFCO issued its standards for the first time in 1969, it’s updated them since to reflect updates in the nutritional science, but that means that since the 70s, pet food has been pretty standardized.

ANTHES: So when I was growing up you know, in, in the eighties, I remember basically all dogs ate was kibble. You know, you gave them dry kibble or, or maybe canned food, but, there wasn’t a lot of choice.

GRABER: Maybe not a lot of options, but there were some very memorable ads and jingles from that decade:

DOG: Kibbles and bits, kibbles and bits, I’m going to get me some kibbles and bits, kibbles and bits. [PANTING] I’m gonna get me some kibbles and bits…

CAT: Meow, meow, meow, meow, meow, meow, meow, meow, meow, meow, meow, meow, meow, meow…

VOICEOVER: Meow Mix! A taste so good, cats ask for it by name.

CAT: Me-ow!

TWILLEY: But over the decades, your basic kibble started to seem… well, kinda basic.

[DOG SNORING]

VOICEOVER: Believe it or not, dogs get gray whiskers too. And as they get older, their needs change.

ANTHES: So, you know, you now have kibble for large dogs and small dogs, and for large dogs that are old.

COREN: There are, I would argue, almost an infinite number of variations. Based on, you know, activity level and age and breed.

VOICEOVER: This is a Labrador retriever. This is a golden retriever. They may seem similar, but when you take a closer look, the details tell a different story. These dogs eat, digest, and process energy differently. At Royal Canin, we obsess over these details.

GRABER: AAFCO now recognizes different life stages and has minimum nutritional requirements for those. Like, say, a kitten or a puppy will need more protein in their feed, as they’re still growing. But the different diets for different breeds?

COREN: I would venture to guess a lot of that is marketing.

TWILLEY: This is how you charge more for something that is otherwise essentially the same. James Spratt realized this a hundred years ago: he started selling Greyhound Cakes, and Puppy Cakes, and Patent Cod Liver Oil Old Dog Cakes, in addition to his regular Patent Fibrine Cakes.

GRABER: This approach is super profitable. Pet food already has a high profit margin—it’s about the same as human junk food, which you have heard is pretty cheap to make and so makes companies quite good money. And the science-y versions of pet food have even higher profit margins.

TWILLEY: But more recently, there’s been kind of a backlash against Big Pet Food. These days, the cool pets are all being fed ancestrally appropriate raw foods, and carnivore diets, and fresh, never-frozen gourmet meals. So are these premium options the best way to feed our pets? That’s coming up, after the break.

[BREAK]

GRABER: Over the past few decades, there have been a number of human food trends that we’ve talked about on the show before. There’s the paleo diet, and the carnivore diet, and the ancestral diet. These started a few decades ago and became increasingly popular over the years. And, surprise surprise, these trends have shown up in pet food too.

TWILLEY: The father of paleo for dogs is an Australian vet by the name of Ian Billinghurst, and he called his diet the Biologically Appropriate Raw Food diet or BARF for short. Here he is explaining the BARF diet in a recent interview.

IAN BILLINGHURST: This is the simple understanding you need to have of why you feed raw, because it’s what dogs, and cats, are designed by evolution to eat. It’s the gold standard. So, so what I discovered over time was the further you vary the diet away from what evolution designed for our dogs and cats, the greater the problems you get. So that was BARF.

GRABER: The idea is that dogs are descended from wolves, and so they should be eating what wolves eat. Companies now sell foods that are raw or super heavy on the meat.

VOICEOVER: So we’ve created a food that satisfies many dogs’ wolf spirit. Grain free Blue Wilderness. It contains more of the meat dogs desire.

ROB LOWE: I’ve done a ton of my own research. And hooked up with some of the most well-known dog experts in the world to compile this information.

TWILLEY: Celebrated expert—sorry, *actor* Rob Lowe is one of many celebrities who feel strongly about the importance of raw, grain-free pet food.

LOWE: And that’s when I hooked up with Dr. Gary Richter. The guy voted America’s favorite vet. I asked him my number one question. If you want to avoid kibble, what should your dog eat so they can stay healthy, energetic, and full of life? His answer, raw food. But not just meat. Raw food includes dog healthy nutrient dense foods, including organ meats, certain fruits, veggies, and herbs. These are the foods your dog evolved to eat in the wild.

GRABER: These trends started to emerge in the 1990s, but they really picked up steam after a massive pet food recall in 2007.

NPR HOST: The Food and Drug Administration has blocked imports of wheat gluten from a company in China because they were contaminated. Tainted food is suspected to have caused kidney failure in dogs and cats across North America.

TWILLEY: The wheat gluten was contaminated with melamine and cyanuric acid, which made it seem higher in protein. But was also unfortunately toxic.

KELLY: So, they recalled like 200 brands of cat and dog food. Which was just huge. Really sweeping. And the FDA estimates kind of vary, but thou, you know, thousands of cats and dogs died from that. ‘Cause they ate the products before they were recalled.

GRABER: This gave a boost to alternative pet foods, like that Rob Lowe raw food diet. But it turns out that Rob Lowe and Gary Richter and Ian Billinghurst, Dr. BARF, they’re wrong.

TWILLEY: First of all, as we’ve already discussed, dogs are not wolves. They haven’t been wolves for millennia, and like us they are evolutionarily adapted to an omnivorous diet, not a carnivore diet. Because they are adapted to eating grains, it’s not surprising that scientists have found that feeding your dog a diet that doesn’t include grains—and especially whole grains—is associated with health risks, including heart problems.

GRABER: Cats are carnivores. What that means is they do need particular amino acids that are not found in plants—they only come from meat. It doesn’t mean that they can’t digest grains. They can, they can extract a lot of important nutrients from grains, and there’s even some evidence that consuming grain-based fiber helps them regulate their glucose levels, which is why researchers have concluded that a moderate amount of grains is a good thing in cat food.

TWILLEY: But most importantly, grains or no grains, neither cats nor dogs should be eating raw food. There is no good scientific evidence for any benefit to dogs and cats from eating raw food, and there’s plenty of evidence of harm.

ANTHES: Most foods for pets are normally heat treated, cooked, pasteurized. Raw foods are not processed that way. So that means that if there are pathogens in there—salmonella, E. coli, things like that, that might be destroyed by heat treatment. They are not destroyed. This is a problem that surfaced recently in terms of the bird flu epidemic. Bird flu is infecting a lot of the commercial poultry in this country, and some of that poultry gets used in pet food.

BROADCASTER: A warning is going out about raw pet food now that new cases of bird flu are being reported in two New York City cats. And one of the pets, a little kitten, died from the infection. The city is investigating the outbreak and warning pet owners to avoid using raw foods and milk. A vet says the sick kitten was fed Savage cat food. The kitten had to be euthanized.

TWILLEY: So raw food is not the answer. But like we say, especially since that big recall, people have been looking for alternatives to big industrial pet food, and they’re willing to spend money on it.

KELLY: I mean, we do see dogs as family members, so. We want to feed them the best and make sure we’re feeding them something that we trust is healthy for them.

GRABER: This view of pets as family members isn’t the way it’s always been, it’s relatively new. As we said, we first saw both cats and dogs as kind of things that were useful to have around, and then over time they moved into our homes. And now they’re family, even more so today than just a few decades ago.

ANTHES: They’ve sort of become more humanized. More and more of us—and I include myself in this—sort of treat our pets… not that differently than children. Or than any other human member of the family.

KELLY: With millennials and, and Gen Z, those generations have, have fewer kids. You know, dogs do become kind of- more of that fill that kind of role of the, the… child, I guess, so to speak. And so, yeah, I think people are willing to kind of go above and beyond to… to feed their dog certain things that even you know, fifty years ago would’ve been kind of un unfathomable.

TWILLEY: When Rachel says unfathomable, she’s not wrong. This is a clip from a recent docuseries about neighbors on HBO. This is a real live person describing what she feeds her dog.

WOMAN: With Cooper in my life. You know, I feel like I have a child in the house all the time. So, Cooper’s meal consists of sushi grade salmon, chia seeds. Organic broccoli, goat liver. Beet kraut, chicken heart, chicken foot. Sardine head, flaxseed oil. And bee pollen. He’s on a raw diet and the first thing he goes for is his chicken foot.

GRABER: This woman is not the only person who makes her pet food at home—even if most people don’t include bee pollen and goat liver. But for people who want those premium steak dinners or that sushi grade salmon for their pet without the work, there are lots of companies who will make that for you.

COREN: It’s Texas style barbecue beef, or Spanish paella. as the, you know, the farmer’s fresh food. Many, many of the pets eat better than I do.

VOICEOVER: At Fresh Pet, we believe that feeding fresh food is the best way to keep our pets healthy and happy. That’s why we make our food with only fresh, wholesome meats and veggies. Now we’re introducing Fresh Pet custom meals. Fresh food that’s perfect for your dog. Delivered right to your door! Always fresh, never frozen.

TWILLEY: Saying fresh never frozen is the quickest way to drive me completely bananas—it is totally meaningless, as you’ll know from reading my refrigeration book. But anyway. I’m sure all these gourmet meals are delicious. I mean, I love Spanish paella.

GRABER: But are these special options better for your pet? We’ve already established that raw food diets are not a good idea, but what about these seemingly home cooked versions?

TWILLEY: One interesting data point about today’s premium foods is that they result in less poop—less than a quarter of the poop you’d get if you fed your dog 1980s style generic kibble. And the poop you do get is apparently firmer and easier to clean up.

GRABER: That’s great for people taking their dog on a walk, or for owners who have to be at the office for a lot of the day, but it’s actually not so great for dogs. As we said, they’re omnivores, they’re meant to eat a lot of different foods, not just mostly meat. Historically, over the past however many thousand years, their diet had a lot of fiber in it. And so they apparently used to poop more in line with that generic kibble diet poop. It’s a better option in terms of colon health.

TWILLEY: Apart from that end of things, it’s actually really difficult to tell if pets are healthier when they eat premium pet food, or even if they’re healthier eating commercial pet food versus table scraps. We’ve talked on Gastropod before about how hard it is to measure how changes in human food affect health over time. But for pets, it’s even harder, because there’s no baseline data and very few independent studies.

GRABER: There’s some evidence that pets are living longer these days than they had in the past, but that’s nearly impossible to pin to their diets. They also go to the vet regularly, and get shots, and eat food that’s heated and pasteurized, so it’s safer, and aren’t exposed to all sorts of harms that they would have run into just nosing around outside.

TWILLEY: What we do know is that, like us, our pets are now obese.

ANTHES: Obesity in pets is an enormous and, and growing problem. The latest statistics I’ve seen suggest that more than 60% of American pets are overweight or obese. It can increase the risk of diabetes and, and other illnesses in older pets. My dog’s aging now and, and probably could lose a few pounds. You know, it can increase the risk of, of arthritis or, make the heart have to work harder. So it’s widespread. But there’s still a lot sort of we don’t know about all the health consequences.

GRABER: One more than slightly overweight dog is a star in the delightful TV show All Creatures Great and Small.

MRS. PUMPHREY: I don’t know why this keeps happening. I only feed him the very best food.

JAMES: Ah, well. That could be part of the problem. What exactly is it you’re feeding him?

MRS. PUMPHREY: Oh! The usual. Chicken, beef Wellington, plum duff. And he absolutely adores trifle.

TRISTAN: Who doesn’t? Good boy.

MRS. PUMPHREY: And cake. Of course.

TWILLEY: Of course. Life without cake is hardly life at all. How could you deprive a dog of cake?

ANTHES: Food is very much how a lot of us connect with our pets. You know, they, they can’t… speak. They can’t express themselves in the same way that that humans do. But we know that, that most of them like food. They- you know, when you’re trying to bond with a new dog or cat, it’s often by giving them treats. It’s how we sort of show our love to them.

GRABER: We do this for our fellow humans, too, obviously, it’s a large part of why I love to have friends over for dinner.

ANTHES: But I think it’s especially pronounced for animals because a lot of the other tools we have to sort of connect with and, and bond with other people aren’t available to animals. So we show our love to and bond with our pets often through food.

TWILLEY: But as in the case of Tricki Woo, the pampered Pekingese of All Creatures Great and Small, this kind of treat-based love language can backfire.

JAMES: Tricki Woo is becoming dangerously overweight. He’s struggling to breathe.

MRS. PUMPHREY: But he’s been so listless, Mr. Herriot. I thought he must be suffering from malnutrition. So I, I’ve been giving him a little extra between meals just to build him up.

JAMES: Dare I ask…?

MRS. PUMPHREY: A little calves’ foot jelly. Cod liver oil. Beef Wellington, and um… A bowl of Horlick’s at night. To help him sleep.

GRABER: Mrs. Pumphrey, Tricki Woo’s owner, she is absolutely certain that Tricki Woo couldn’t possibly enjoy life without his beef Wellington.

TWILLEY: And a classic British sugary malted milk drink for sweet dreams!

GRABER: But Michael says that our pets don’t come into existence craving the finest pate.

COREN: So yes, every dog—it seems like every dog loves bacon. Or would love a little bit of your steak. And that is probably true on some level. But when I talked to veterinarians, they actually said most of the preferences that our pets have are preferences that we create. And we create them because we basically give them things over time. And they learn to like those things.

TWILLEY: So Tricki Woo could survive and maybe even thrive on kibble. But, apart from the microbial dangers of raw food and the health implications associated with overindulgence, and of course the damage to your bank balance from the cost of feeding your pet a premium diet—is there any real harm from your dog or cat dining on the finest foods in the land? Assuming you do it safely and in moderation, and can afford it?

GRABER: Well, there’s certainly an environmental impact. If you listen to Gastropod, you likely know that the industrial meat complex has some environmental issues.

COREN: Obviously, you know, the meat industry is huge source of emissions. And it is about 20% or so estimated, about the animals that are slaughtered in the United States do come from sort of the pet food for the pet food industry. It’s not just castoffs and, and extras. The number varies, but we’re talking on the order of two billion animals each year.

TWILLEY: You might think that because pet food is largely made of parts of the animal we don’t typically eat these days, that in reality its impact isn’t too bad. That’s certainly the argument that gets made: that the pet industry is a way to reduce waste.

COREN: That’s what I assumed as well.

GRABER: But actually, it’s not that simple.

COREN: So two things are happening. One is a lot of these are prime cuts, like some of the fresh meat—the high end premium are just cuts that you would normally human grade food. And then when I looked into the industry at large. When you look at the economics of the livestock industry and sort of like what it, what it takes to raise them and what makes it economical. The pet food industry was just a, a big source of demand and it wasn’t just things that would’ve thrown in the trash.

TWILLEY: In other words, if there were zero pets at all, the meat industry would still have no trouble selling all its byproducts to go into fertilizer and glue, lubricants, soaps, drywall, baseball mitts, cosmetics, pharmaceuticals, you name it. The pet food industry isn’t using waste, because if the pet food industry didn’t exist, the byproducts wouldn’t be waste. There’s a big market for them.

GRABER: And so because the pet industry DOES exist, and those industries still also need animal byproducts to make their products, that means that even more animals need to be raised to feed all the pets.

COREN: Yeah, this was, this was eye-opening for me as well. This is not just things that would’ve been wasted, it is just part of the food system.

GRABER: You all know that the environmental impact of meat isn’t just a climate change issue, it’s also water and polluted runoff and land use—the land used to raise all that meat.

COREN: It’s, it’s something on the order of the area size of Mexico. So that is, you know, quite a large, large area just for using livestock for the world’s pets.

TWILLEY: And premium brands have around triple the impacts of normal kibble, because they have so much more meat.

ANTHES: So if you live in a city, you don’t have a car, you don’t fly very much, but you have one or two huge dogs who are eating high-end human grade dog food every day, that could be a substantial part of your carbon footprint. So it’s not the main culprit by any means, but it certainly contributes.

TWILLEY: So what is a climate conscious pet lover to do?

GRABER: Well, there are new more environmentally-friendly protein options, like insects.

ANTHES: You are seeing companies making like, insect-based snacks for humans and, and things like that. For a variety of reasons, they’ve been sort of a hard sell. And so some companies are now exploring the pet food market.

TWILLEY: We’ve made an entire episode about eating insects too, and Emily is right, many humans in the developed world have been slow to add them into the mix. But they are typically a much more sustainable source of protein than basically any livestock or fish, in basically every way you can imagine, so if pets are cool with insect protein, that sounds like a real win.

ANTHES: I conducted my own in-house taste test. I have two cats and a dog. The two food motivated pets were happy to eat anything I put in front of them. Which I think is another reason some of these companies have their eye on the pet market. You know, pets usually aren’t picky. I have a third pet, a, a cat who’s picky and wasn’t quite as sure about the insect food. But certainly my experience—my dog and one of my cats were happy to eat insect treats and insect kibble. I’ve heard anecdotally about lots of other pets that are too.

COREN: Miska, my husky, loves the Jiminy Cricket treats. She prefers those over the other ones at this point.

GRABER: That sounds great, but as we discussed on our insect episode, insect growing companies are still having a hard time scaling up and making money, so it’s not clear that they’ll be able to meet the needs of the broader pet food market in the near future, even though it’s certainly a good option.

TWILLEY: So what about just cutting out animal protein altogether? I mean, going vegetarian has huge environmental benefits when humans do it, not to mention avoiding the animal cruelty that is such a huge part of industrial meat. Could our pets go veg, too?

GRABER: It turns out that yes you can buy entirely vegetarian pet food today.

COREN: So it, you know, it’s, it’s emerged over the last few decades. And it hasn’t really taken off until very recently. It’s not always been feasible to do. We, you know, first had to understand what all the nutrients were, and then understand how to, how to synthesize them. And, and do them, and then do, do food trials. And basically see if it was effective.

TWILLEY: Feeding pets a plant-based diet does intuitively sound wrong. But we’ve already established that dogs are not wolves and so they, like humans, can be perfectly healthy on a vegetarian diet. That said, cats do need amino acids that you don’t find in plants.

COREN: Without that they have heart problems, and things like that. The difference today, though, is that you can actually get a lot of those nutrients from non-animal sources. And the veterinarians I talked to were much more blasé about dogs than about cats. But there have been studies that shown that cats have have thrived on these diets as well as long as they’re carefully formulated.

GRABER: Studies on dogs also show that they’re totally fine and healthy eating vegetarian food.

COREN: And in studies they’re actually finding that: that not only are most pets fine with it, but they’re actually healthier and living longer.

GRABER: These studies are still pretty early, and they’re showing maybe a year, a year and a half of extra life, which is not insignificant for dogs. But like all these nutrition studies, there are a lot of variables at play. And also some studies don’t show any increased life expectancy.

TWILLEY: But they’re also not showing harms—and in fact, there’s even been a big benefit at least for pets that have allergies. I had no idea this was an issue, but Michael says almost all of pet allergies are to meat proteins. And so switching pets to a vegetarian diet avoids all those triggers.

GRABER: And in fact, it’s the health aspect that’s a bigger sell for pet owners. That’s what the insect pet food companies told Emily.

ANTHES: They told me they learned pretty quickly that the sustainability argument was not enough to win over pet owners. Or at least in, in most cases. And that what pet owners care about most, which is—maybe should not be surprising to anyone, is their pet’s health. And so, you know, more sustainable pet food is great, but is it going to be good for my pet and can I afford it?

TWILLEY: The owners do buy the food, so what they think probably matters the most. But we were curious: what do the pets themselves think of vegetarian food?

COREN: The one I have tried is veggie supreme. So it was Wild Earth. And it’s basically a mixture of barley and oats and dried yeast and sorghum and potato protein and millet, canola oil, spinach, vitamins and minerals.

GRABER: When Michael says “I” have tried it—he hasn’t tasted it himself, he’s talking about his husky Miska.

COREN: We’ve transitioned to that over about a week or two, and she’s kind of never looked back. I mean, she, she obviously would love to eat everything on the table, and she often does. But in terms of her daily kibble, she asks for it and she’s excited about it. And we, we really haven’t had a problem.

TWILLEY: The potential benefits of switching pets to vegetarian diets are huge. People who have done the math say that if all dogs switched to a vegetarian diet, it would reduce global greenhouse gas emissions by six percent. Which is more than if all of us never flew on a airplane again.

COREN: So basically when you look at how much emissions is emitted per pound of pet food for plant-based, it’s going to be about 10 times less than it is for meat-based ones. And even more if it’s beef.

GRABER: Michael recently wrote a column for the Washington Post about this topic, about the climate benefits of vegetarian pet food and his experiments with it. We were wondering: what was in the comments section?

COREN: [LAUGH] I would say people have very strong opinions. Some were, some were very, very supportive and, and have done this for a long time and say it’s great. I think the biggest feedback I got in support of it was that it helped their pets with their dietary and health issues. People are shocked at how many of these issues are related to the diet, and it clears them up. Because you just don’t have a lot of these allergens and, and, and other issues. And, and tends to be a little lower calorie.

TWILLEY: But not everyone was on board.

COREN: A lot of people were very negative. Because they felt that either dogs were carnivores, which they are not. Or cats are carnivores, which they are, and they could not possibly survive on something without that.

GRABER: Despite this widespread belief, Michael says that if the pet food has the AAFCO stamp of approval, then it has the nutrients your pet needs, even if it’s insect-based or plant-based. And so even if that fresh human-grade turkey dinner seems more delicious to you, maybe it’s not what’s best for your pet, or the planet.

COREN: You know, we love our pets, we love our family, and so we want to give them the best. And. I think we may be project a lot about what the best is. And what’s best for your cat or dog is just not the same as what’s best for you. Yeah, I think, I think we need to take a little bit of a step back and, and just think about, you know, what do they really want? What do they really need? And maybe less about what I need or want. [LAUGH]

[MUSIC]

TWILLEY: Before we get to our thank yous this episode, we just want to ask again: if you can support the show, at any level, we would be eternally grateful. We’ve got lots of fun rewards, including, at the special supporters level, a bonus newsletter for each episode.

GRABER: The newsletter for this episode is all about GLP-1s for pets! Emily told us that a lot of pets in the US are obese these days, and she wrote in the New York Times about treating obese pets with these new drugs. In the newsletter: is this a good idea? And what are the ethics of giving pets these drugs? Sign up and find out!

TWILLEY: Thank you so much to all of you who help us make this show. We could not do it without you. And thanks this episode to Rachel Kelly, Emily Anthes, and Michael Coren, we have links to their work on our website, gastropod.com.

GRABER: Thanks also to our fantastic producer Claudia Geib and her dog Oona, who so patiently waited for Claudia to mic her before she chowed down on her kibble and vegetable stems. We’ll be back soon with a brand new episode, till then!