Guts
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Terms apply. Learn how to get more out of your experiences at AmericanExpress.com slash with Amex. Listener supported. WNYC Studios. Hey, I'm Alathe Fnasser. This hour, we dive deep into the vault back to 2012 to explore the grotesque tube slide that lives inside all of us. I mean, it seems straightforward, right? It should be like...

Every day, several times a day, put food in your mouth. Sometime later, comes out the other side. But what really happens in between? Now, I so vividly remember listening to this episode when it came out. What I still love about it is it's just this idea that one errant gunshot wound is

opened up this portal for us to peer inside ourselves and to see what's actually going on in there in real time. And that what we saw

so much of what we thought we knew about the kind of messy mystery in the middle of us. I have a feeling, call it a gut feeling, that you're going to enjoy it. So without further ado, I give you Guts, best enjoyed after a meal. Wait, you're listening? Okay. All right. Okay. All right. You're listening to Radiolab. Radiolab. From WNYC. WNYC? Yeah.

Rewind. Hello. We're going to start this show today. Hey, Mary. With Mary Roach. Hey. Tim here. Hi, Tim. Hey, let me see if I can... Mary is one of our favorite authors, mostly because she kind of writes about stuff that's...

Yucky. Gross. I'm the kind of person, if I find myself in an operating room for whatever I'm reporting on, I'm the kind of person where they'll be like, Ms. Roach, you need to step back. Your head is actually inside the body cavity. And for her latest book? Called Gulp. She got really, really into and inside Gulp.

Yeah, the fistulated cows that the agricultural schools have. And what's a fistulated cow? A fistula is an irregular anatomical passageway. And a fistulated cow has a hole right in its side so that you can actually stick your hand into its side and reach all the way down to the stomach.

This is a living cow, right? It's a moving... This is a live cow. And you've done this? Yeah, it was. It was this amazing... Because, really, you know, a cow is... She did it at the University of California, Davis. You're just... You're standing there sort of normally, and for some reason I've worn...

a skirt and kitten heels and my hosts are wearing manure encrusted muck boots and it's a source of great entertainment that I'm here. And it's packed really tightly. You got to really work your arm. The guy I was with, Ed DePeters, he's like, no, keep going, keep going. I'm like, I don't know, Ed. I'm not sure, really. Go further in? Yeah, keep going, keep going. And I'm literally up to my shoulder inside this cow. I so want to do that.

Where are you guys? We're in New York. Yeah, I know where there's one out there. I can get you a fistulated cow. You want to walk them down towards the barn and I'll go get the group? All right. I didn't actually get to do it, unfortunately, but we sent our producer, Tim Howard, out to Rutgers University, where a bunch of high schoolers had come to see Lily, the fistulated cow. Okay, let's give it a go. I'm going to pop the cork. All right.

Did he say cork? Yeah. You have to uncork the hole in the cow. You see all the steam coming out? Ready? All right. This is Tim reaching his hand in. Go straight across the top to the far side. Okay. Oh, my God. It's powerful in there. Oh, God. I mean, I was a little worried it was going to break my hand. You mean like pressure? Yeah.

Yeah. It's a very muscular organ. It's coming to my arm. Mixing and... Wow, I can feel the side of the stomach pushing against me. Squeezing and contracting and... Wow. It's really squeezing. It's groping you back. I'm stuck. So I'm just going to try to go a little bit deeper. And it's hot. It's steamy. I don't know, it's like bubbly. It's physical. It's very...

Yeah. And she is so calm right now. I can't believe it. The cow's bored, and I've got this look on my face like I've seen God or something. I'm like, whoa! Mary says that for all her times in morgues and all the places she's been, this one was really different. The expression I was wearing, I'm sure I've never had cause to use. And here's why.

If you think about it, the stomach is a center of magical transformation. That is Fred Kaufman, who wrote a whole book about the stomach. You take something outside of your body, you put it in your body, and it turns into you. So it's like this conduit between what's outside you

And what's inside? The other thing that's weird is that the human body is a torus. We're donuts. We've got a hole going through the middle of us, all the way through us. So what seems to be inside us, what seems to be inside our stomach, actually is always outside us. Oh, this is getting so deep.

You don't like the Taurus? No, I think it's great. I think I'll go with it. Because I was thinking we could start that way. Because that's what we're kind of doing this hour. We're going to take this thing that's deep inside us. And turn it inside out. Yeah. I'm Jad Abumrad. I'm Robert Krolwich. This is Radiolab. And today, guts. That mystery that lies between our mouth. And our butts. We are these sacks of guts.

And these skeletons, and we walk around, and we never even see them. And for centuries, nobody really knew what's going on in there. But then something happened that opened up a window. Yeah. Do you want to start back at the beginning of it? Yeah, let's once upon a time it. Okay.

So once upon a time, it all begins. And when is this? They first met in 1822. Once upon a time in 1822, there was a guy named William Beaumont. William Beaumont is a farm boy from Lebanon, Connecticut, five brothers and six sisters. And William clearly is the smart one. He was the one with the big dreams.

So at an early age, he leaves home and gets himself a job as a doctor. An army doctor. Up north. At Fort Mackinac, which is this, it's a trading post basically. So Beaumont, he has a little doctor's office at the top of this hill. And at the bottom, there's a general store for fur traders who would come in from Canada. Super hardy dudes. Like it's cold up there and they're going out in canoes and they're running with these huge packs.

I imagine big beards. Sure. In any case, that was all just set up. Here's the actual story. One day, June 6th, 1822, normal morning. All the fur traders come in and are unloading and loading. Getting their coffee, salted meat. Supplies to go out. Trap some fur. When all of a sudden, boom!

Right outside the shop... Somebody's gun went off. Somebody calls Beaumont. Beaumont... Dashes out the door... Runs down the hill, finds this guy... This 18-year-old kid... Really in bad shape. The kid's lying on the ground. He's a big guy, muscular. But he's covered in blood. And he has a hole... Right below his ribcage. About the size of the palm of a grown man's hand. Nobody was sure what happened, but someone's gun had gone off... By accident. And shot this boy point-blank. His lungs are dripping out. There's blood everywhere.

This is what Beaumont sees when he shows up. This is what Beaumont sees. And the other thing Beaumont sees is food coming out of his stomach. Meat and bread and coffee. Yeah. Basically, the remnants of his breakfast spilled out. On the ground, right in front of him. You can kind of see the gears turning in Beaumont's head as if he's thinking, Whoa, there it is. Digestion in action. Which was kind of disgusting. But it was also something of a revelation because in 1822, the stomach was an area of mystery.

Just like today we're aware the brain is an area of mystery. And for centuries, people believed that the stomach, more broadly the gut,

was in a very real way the center of our beings. Yes, in Puritan times, the bowels are the seat of human sympathy. You know, where our deepest feelings come from. If you have bowels for somebody, that means you sympathize with them. Oh, is that something people would say? Absolutely. Oh, we should bring that term back. That's very interesting. I have bowels for you. Point is, medical science was pretty fuzzy in what happens down there. I mean, they knew it was important, but they had no idea how it worked. Like, how does food work?

Become us. Nobody understood it. Because they can't see. You can't directly observe it without opening the person up. But here was a guy open right up. But of course, Beaumont is a doctor, so he's like, wait, I've got to save this guy. So he starts sewing him up frantically. Pretty sure this fellow's not going to make it. And he was surprised that two days later the guy was alive.

Really surprised. And as the months passed, this kid... St. Martin. That was his name, Alexis St. Martin. He gets better, but... A year later, he still has this hole in his stomach. The hole never closes. What happened is he grew a fistula. Just like the cow we talked about earlier, except in this case, he didn't have a cork where he was wounded. He had a flap of skin covering the hole. If you wanted to, you could just pull back the flap and look inside. And we don't know if Beaumont left it that way on purpose...

What we do know is that he sees an opportunity. To make the body give up its secrets. He sees he's got something that nobody else has. Maybe he even thinks. This man could be my ticket out of being a lowly Fort Mackinac doctor. So Beaumont kind of hires him as a man around his house. As a manservant. You know, he said, oh, it was a charitable thing. I wanted to help him. Yeah, because it couldn't work. And I'm thinking, oh, maybe, maybe not. And so about a year later, he starts. Come on in.

he starts his experiments. Oh my lord, this is straight out of a movie. While reporting this story, we ended up visiting the rare book room at the New York Academy of Medicine, which is pretty much the coolest room ever.

It's all mahogany and they've got like ancient skulls sitting on top of bookshelves and the books are hundreds and hundreds of years old. In any case, the librarian Arlene Shainer showed us around and then put on some white gloves, disappeared between some stacks and came out with a little purple book. Beaumont's Observations. Experiment 1 is on August 1st, 1825.

So at 12 o'clock, I introduced through the perforation into the stomach the following articles of diet. So what he does is he takes different foods. A piece of raw salted fat pork. Some corned beef, you know, like a one-inch square of corned beef. A piece of stale bread. And he attaches them to a silk string and he inserts them. Through the artificial opening into the stomach. Into the stomach. And I hope the end.

for an hour then he takes it out like a fisherman yeah yeah he's fishing he's he's doing stomach fishing and he takes it out and he records you know so it was an hour later how much uh was digested withdrew and examined them found the cabbage and bread about half digested

The pieces of meat. This went on for hours. Returned them into the stomach. At 2 o'clock p.m., withdrew them again. In hours. Returned them into the stomach again. For years. Over the next few years, Beaumont puts anything he can possibly think of into that stomach. Pigs' feet soused take an hour. Animal brains boiled take an hour and 45 minutes. Fresh eggs hard-boiled take three hours and 30 minutes.

Soft-boiled take three hours. Fresh eggs fried take three hours and 30 minutes. Fresh eggs roasted take two hours and 15 minutes. Look, it's just the totality of food in America at that point. Whipped eggs take an hour and a half. He's trying everything. Baked custard takes two hours and 45 minutes. Oh my God, that goes on for pages. It goes on and on. Alexis St. Martin is...

becoming increasingly irritable about this whole process. I would imagine. Because a lot of times the things that Beaumont would stick into his stomach would make him sick. Give him a fever, pain in his head, depressed pulse, dry skin, coated tongue. So in 1825, three years after this all started, St. Martin finally bolts, goes back to Canada, gets married, even has a few kids. All the while...

Beaumont is writing him letters, trying to lure him back. And he was offering him, okay, I'll pay for your family. Okay, I'll give you $50 a year. Okay, I'll give you $75. And he was like, I'll throw in the land. Because, you know, he still wanted to know. Like, all right, fine, it takes... Three hours and 15 minutes. To digest a carrot. Oyster soup, three and a half hours. Or soup, whatever. But how does it work? How does the stomach do it?

And eventually, because he needs the money, Alexis St. Martin does come back. Beaumont starts his experiments again. And one night, while Beaumont is peering into the boy's stomach...

He gets his answer. He says he applies a few crumbs of bread to the inner surface of the stomach. Immediately afterwards, small, sharp papillae became visible. He saw little pimples form on the wall of the stomach. And out of the pimples? Exuded a clear, transparent liquor. Outsquirt some juice. Outsquirt some juice. ♪

And that was it. That's the magic juice. Clear, almost transparent. Tasted a little saltish and acid. Ooh. Might apply to the tongue. Yeah. Tasting. A lot of tasting went on. And then... He would collect...

the stomach acid and see if you could digest outside the body. There was this theory that the body had this vital force and that that was necessary for the bodily processes, including digestion. So if you took the stomach acid out, what would happen? December 14th, 1829, at 1 o'clock p.m., I took one and a half ounces of gastric juice fresh from the stomach

put into it 12 drams recently salted beef boiled. The theory at the time was it wouldn't work. You had to have the magical powers of the human body. But digestion commenced. Beaumont, one of his big discoveries was, no you don't. That actually there are no secret forces of sympathy and excitement driving things. It's a chemical. That's what it's all about.

Now, Beaumont didn't know it, but that juice he was seeing? Which he called gastric juice. Those are enzymes. And what enzymes are are like little chemical scissors. They break down food so that you can take something in from the outside, like this carrot, and absorb it. It becomes literally a part of you. The key to the whole thing, the key to life, are enzymes. In a way, they are the magical force.

just in chemical form. That's it. That's the truth. He was the first to understand it, the first to see it, the first to figure out the method of how to prove it. And he proved it.

So Beaumont writes a book about this. And this book is published in 1833. And he becomes famous. People were fascinated by Beaumont's experiments. He would kind of go on these tours. He's called over to Yale University. Gets invited to speak in Europe. Wherever he goes, he brings his gastric juice and he lectures there. From the dude's stomach? Yeah, yeah, he travels around with it. And whenever he could, he would take St. Martin with him. St. Martin was his PowerPoint.

You know, he's like, I need you, man. I need you on the stage so everybody else can come up and stick their tongue in your stomach. For William Beaumont, this works out pretty great. He's thought of as this, you know, tremendous contributor to the understanding of digestion. As for Alexis St. Martin... He was a curiosity. He was a medical curiosity. For the rest of his life... For the day he dies... Even in death... His body is a hot commodity. And his family was very aware of this. They let his body rot in the sun for three days...

and then buried him very deeply and put big rocks over him so he would not be exhumed. Thanks to Arlene Shainer at the New York Academy of Medicine and Fred Kaufman, who wrote a book called A Short History of the American Stomach. And a special thanks to Mary Roach. Her forthcoming book is called Gulp, A Trip Down the Elementary Canal.

Hey, I'm Jad Abumrad. I'm Robert Krolwich. This is Radiolab, and today... Well, we're talking about the interior space that runs down from your mutt to your butt, and it is called... Your gut! Your mutt? What is that? It's just an old person's word for mouth.

Now, as we just heard for a very, very long time, people believed that the stomach was a place of magical transformation. Yeah, but of course, as we know now, it's just a big muscle with acid and enzymes and stuff. But if you travel a little deeper down, down below the stomach, then things get spooky again. We just, you know, we have these sort of shadowy images of what's going on in there.

That's Carl Zimmer, a shadowy figure himself, a science writer, and... Can I get some water? Yeah. And a frequently thirsty man. My throat got a little scratchy. Soren and I called him up, you know, while you were gone on paternity leave? Yep. And he told us, you want a mystery? Yeah, I do. Okay, then the stomach is just a warm-up. Oh, yeah. The 25 feet of coiled, soiled, fetid tubing inside you... You mean the intestines? Yeah, yeah.

That's where the real mystery lies. Because here's the riddle: The part of you that turns the world outside into you isn't just you. It's more like a collective. What does he mean by that? Well, if you zoom into our intestines...

What you'll see is legions of tiny creatures. Bacteria, viruses, fungi, protozoans. And those are all little single-cell? Yeah, we're talking about non-human things inside of me. How many have you got, would you say? Me? Yeah. Probably in the order of maybe a couple thousand species. Mm-hmm.

So there's E. coli, Bacteriodes fragilis, and then another one, another one, another one. It's a whole universe down there. Microbacteria, Fravolbacterium, Bersinia, Dephalopoccus, Acromobacter, Astridium, Acetaminoplasma, Euromonas. Some of them you'll find in all of us. And then there are just a whole bunch of other species that are rarer, might be in one person and not in the other. It's like a rainforest. Oh yeah. There are ecologists now studying your gut, looking at these complicated networks of bacteria

hundreds, thousands of species that are living inside of you and depending on each other or preying on each other. It's just this incredibly complicated pattern that scientists haven't figured out. When you're in an embryonic, what are they called, the sacs? Your amniotic sac. Your amniotic sac. How much bacteria do you have in and about you there? You're sterile. You have none? No. At all? You're clean. Huh. But then as you are coming out...

All of a sudden, you're into this new environment, the birth canal. You're breathing, your mouth is open, stuff is coming into your mouth that's coating your skin. There are lots of bacteria there, the vagina, the birth canal. It's a very complicated ecosystem there. And right after you're born, says Carl, you meet a nurse, then some doctors. You'll go home, you'll play in your backyard, you'll suck on a shoe. You might eat some dirt and get licked by a dog.

And by the time you're going to school, you've got probably about 100 trillion microorganisms. So 100 trillion other kinds of cells in you. Yeah. So if you were to take like all the bacteria in your body and just made them into one lump, it would be about three pounds.

Oh, really? Think of it as an organ. I mean, your brain's about three pounds, your heart's a pound or two. So this is another organ. In this case, it's an organ that helps you digest food. But here's the thing. This place in you, which is filled with foreign critters, somehow this organ gets into your head.

What does that even mean? Wait, just wait a second. Let me introduce you to someone first. Hello, can you hear me? Yes, yeah, we can hear you. John. My name is Professor John Crine. I'm the professor and chair of anatomy and neuroscience here at University College Cork in Ireland. And I'm a neuroscientist. A brain guy? Yep. If someone told me six years ago as a neuroscientist that I'd be here talking about microbes, I would have, you know, laughed it off. But to make a long story short, John found that as he was getting into neuroscience, a lot of the neuroscientists at his university in Cork in Ireland...

They were getting into bugs, for reasons that will become apparent in a moment. And eventually, he got the bug for bugs. And began to work with this one particular strain of bacteria. This is the lactobacillus strain. What was it? Lacto-something? Lactobacillus, sorry. Lactobacillus rhamnosus. It looks like a pill, really. It's kind of an oblong thing. And it's sometimes used to make yogurt.

We were interested in whether if you fed mice with this for a number of weeks, whether it would alter their behavioral state. Meaning if you fed these mice a bunch of this bacteria, would they become very different mice? Different mice? You mean like fatter mice or something? No, no, no, no, no. Would they change their personalities? This is like a profound change.

Because of a bacteria in their stomach? Yeah. Not in their brain? No. Just in their tummies? Just in their tummy. That's insane. That's not going to work. Well, let me tell you what he did. He had two groups of mice. One of them got Palactobacillus. The others, they got just normal mouse food. Yeah, we fed them broth just as a control so it didn't have any bacteria. Then? We looked at how they responded to a mild water stress and...

what we found was that... Mild was a mild one. What does that mean? Sorry. Well, it's water. It's water at room temperature. Basically, what he did is he took these two groups of mice, the bacteria mice and the no bacteria mice, and then he would drop them into a bowl of water.

And all rodents are very good swimmers, but they just don't like water. Oh. Now, what he was looking for was any difference between the two groups in terms of how they dealt with this water situation. Like if one group squeaked more than the other or something? Whatever. You just keep an open mind and you wait and see what's going to happen. Fine.

So here we go. Starting with the first group, the normal ones, he dropped them in. And as you'd expect, they're trying to escape. They're trying to escape. And he timed them to see how long they'd keep at it. Okay. And one minute passes. They swim, they swim to the edge and all around looking for an escape. Two minutes pass. Three minutes pass.

But about four minutes in, he says the mice start to get worn down. And then they decide at this point, there's no point. I'm giving up. Which means what? The ordinary mice just go do a dead mouse float? Yeah, dead mouse float. You know, they just give up. They don't drown. No, no, no. They just sit there and think, I will wait this out until it's over. Exactly. It's been coined behavioral despair. I can't do this anymore.

That is how a normal mouse reacts to being tossed into water. It struggles for about four minutes, it gives up, and then sinks into despair. For the second group, this is the group that ate the bacteria. Yeah. You'd also drop them in the water? Yeah, yeah, yeah. Here we go. At first he says they were just like the first group. They were swimming around frantically for one minute, two minutes, three minutes. But then at the four-minute mark, when the first group of mice had given up,

These mice, they kept going. They kept looking for an out. Past four minutes to five minutes.

Six minutes. So they're not despairing. Exactly. And they might have kept going on and on and on, but he then plucked them out of the water after six minutes. The thing that's kind of strange is like, you know, worrying and scurrying about and panicking. Like that all seems like what it is to be a mouse. And you're saying that bacteria in the gut can change that? Yeah. Wait a second, Sorin. Okay, fine. There seems to be a difference between these two groups, but how do you know?

How does John know that the bacteria had anything to do with it? Well, he didn't just stare at the mice. He looked at their mouse chemistry. By looking at the stress hormones. And what he found is that in the first group, the mice that quit and despaired... We got about a hundredfold increase in corticosterone levels. That's the hormonal version of... Exactly. And in that first group, when he dropped them in the water, their blood flooded with this one.

Which initially, you know, it's not a bad thing because a mouse has to act. But all-out panic isn't great for a little mouse. And after a couple of minutes of hormone coursing through the veins, the mouse just, you know, burns out and shuts down. But in the second group of mice, now these are the mice that ate the bacteria. We found that in the mice fed the lactobacillus, they, well, first of all, they had half as much of that stress hormone. Half. And?

They had another chemical suddenly in the mix. We found very, very distinct changes in the receptors for GABA in a variety of brain regions. GABA? GABA. What's GABA? Well, he says you can think of it as the opposite of a stress hormone. It basically is there to shut down the brain, stop things, inhibit, make us more relaxed, chilled out. And he thinks what's happening is that in these mice that eat the bacteria, they hit the water...

The stress hormones come online. But before things get too intense, in comes GABA, and GABA just goes. And as a result, these mice... They're chilled out, they're relaxed. They're not afraid. They never panic, they never burn out, and they never fall into despair. They behave like as if they were on Valium.

So somehow the mice, the gut bacteria of the mice are sending volume to the brain? Is that what he's saying? That's what he's saying, yeah. But he hasn't said anything about bacteria yet. I mean, it's a long distance. Gut down here, brain up here. Look, John told me that if you look inside a mouse's body, you will find a giant nerve. The vagus nerve. That runs between the gut and the brain. Oh. You mean like a phone line? Exactly. And he thought, well, maybe they chemically tickle one end of the line, send a shiver

signal up to the brain, which then makes the GABA. Now, in order to prove this, he thought, why don't I just cut the line? Basically sever the vagus nerve. Oh, because then if the bacteria are the ones doing it, if he cuts the phone line, they won't be able to do it anymore, and then the mice should go back to normal. Exactly. So, in collaboration with my colleagues at McMaster on

Ontario. He got some mice. We fed them the bacteria again. But this time, before throwing them into the pool, he cut the nerve. And? We found that all of the changes that we had seen... The swimming forever, the not giving up... And the neurochemical changes in the brain... The gaba-shh, making them so calm... Were completely absent.

You cut out the highway and then the communication, the brainy changes stop. Totally. Totally. When they cut the nerve, the mice went back to being quitters? You have to be convinced now. Okay, I'm convinced. So here's my question, though. This is a mouse we're talking about. This is a mouse. Just a mouse. Does this have anything to say about us? I mean, is there any connection to make? Well, I asked Carl that question. There was one study that, where was it?

Oh, oh, you know what? So this was a clinical trial actually done in France last year. That's John Allera, who regularly reports about things neurological for us and others, and he knew about the study too. Yeah, so they fed people just massive doses of probiotics. Does probiotic mean like the good ones versus the bad ones? Yeah, probiotics are the good gut bacteria. They're in yogurt and things like that. So these guys in France, they gave these people probiotics

like sugar-sized packets of powder. And inside the packets, there are two different kinds of bugs. Lactobacillus helveticus and Bifidobacterium longum. Two of my favorites. Oh, yeah. Well, you should like them because I gave them to people. And they showed a fairly dramatic reduction in their basal anxiety levels. They became less stressful and had less anxiety. Because when they took them to high diving boards and threw them off instead of screaming, how do you test these things? Uh,

Basically, they did a little survey and asked questions. How distressed do you feel? You know, they took levels of stress hormone. You know, so they had some quantitative measures. People who took those probiotics said they felt better.

less angry, less anxious, and less depressed. Wow, so the gut bugs have us on a chain too. Yeah. Because we have, you know, one thing to remember is like, you know, our mood, a lot of the way our mood is set is through serotonin. That's like when they do antidepressant drugs, it's the serotonin reuptake something. Yeah, so you're controlling the amount of serotonin that's going in and out of your neurons. Right. You have very little serotonin in your brain, but it makes a huge difference. Yeah.

You have a huge supply of serotonin in your gut. 80% of all the serotonin in your body is in your gut. Really? Yeah, and the bacteria can be feeding on that stuff. It could be that they— You have an oil well of happiness in your gut, and if you get the right pump, you could feel happy more of the time. It's one possibility. So, Jad, when you and I are sitting around feeling all stressed and anxious, or if we're just happy and gay in the old sense—

Now we know this mood is shadowed, influenced, and shaped by the bacteria you have in your intestine. The kinds of studies that show this effect, they've all happened in the past couple years. And that's it, period. But there's this review, it was in the Proceedings of the National Academy of Sciences, where

was just kind of commenting on a couple of these studies and saying like, "Hmm, let's think about which bacteria we should focus on for psychological treatments. Let's think about how we can treat people's psychological disorders with bacteria this way. Let's just think about it." This is in the Proceedings of the National Academy of the Sciences. They're talking about treating psychological disorders with yogurt. Yeah, medicinal yogurt in the future. But medicinal as in Prozac?

Sure. Medicinal as in whatever they give to people with schizophrenia. I don't know. I mean, who knows? I mean, who knows what will work and what won't work? It's just, but it's something that people are saying, like, we need to look into this. There's something for me a little poetic about the fact that a lot of our moods come from the same organ that produces s***. I mean...

I haven't put my finger on what's poetic about that, but it just, I mean, it does make a little bit more sense when you step back and think about this from the perspective of evolution that, you know, our biggest decisions way back when were what to eat. Is this going to kill me and make me sick? Is this food spoiled? So it makes sense that the part of the body which can detect that is also intimately connected with decision-making systems that have to do with this going to make me happy or this is, I should fear this and not eat this. Hmm.

So as outlandish as it seems that, you know, the self is connected with the part of the body that produces s***, it also has a little bit of engineering logic to it. Special thanks to Carl Zimmer. His latest book is called Science Inc. It's a description of tattoos that people get on scientific themes, and you can see them on their arms, their legs, thighs, and embarrassing places.

Okay, ready. Hey, I'm Jad Abumrad. I'm Robert Krolowitz. This is Radiolab, and this whole hour we have been talking about... Go ahead. Guts. Guts. In the last section, we talked about bacteria and the armies of them that are in your gut. Yeah, the problem is that they're a little hard to picture, kind of abstract. Why don't we finish with a story that makes the whole issue real and much more concrete. This is the tale of a troubled relationship between a man...

And his on-again, off-again gut. Yeah. Hello. Hello. Hello. Man's name is John Reiner. He's a writer, lives here in New York. So one day you are eating your way through your life as you usually do, and then things take an odd turn. Yeah. How did it begin? It began with a surprise. ♪

I was at home and I was about to go make myself a tuna fish sandwich. John thought, you know what, let me go to the bathroom first to get that out of the way. So he sits down on the pot to do his business. And I felt a funny twinge in my gut.

Now, John has had gut pain before. I suffer from something called Crohn's disease, which is a gastrointestinal condition. But I had gone through a period of about a year's remission. Excellent health. And so when this pain came on, John figured, no big deal. It seemed to come out of nowhere, and I thought, it'll go away out of nowhere. Like usual. But it didn't. Within about, you know, a minute, what was a small twinge all of a sudden felt like a knife stabbing.

into my gut. Before long, I'm on my living room floor, flat on my back, and I can't move. John calls an ambulance. They rush him to the hospital. When they get there, the doctors take one look and tell him, your intestines were clogged, and now they've burst. And it's now spreading bacteria throughout your system. Basically, you're on the verge of having sepsis. Meaning you could die. So you need emergency surgery, but they also told him that I should recover.

And when he came out of the OR, it looked like he would. But the doctor said, let's play it safe. Stay here for a week. We'll feed you through an IV and give your gut a break. So I'm on an IV for a couple of days. And I've been on nothing by mouth in the hospital numerous times before, but always for four to five days. And after four or five days, John says, what normally happens is that you'll start to feel hungry again. And that's a great sign. That means that your gut is healing and it's ready for food. But this time, that didn't happen.

In fact, he says he got sicker. Nausea, vomiting, chills, fever spike. So the doctors take more pictures of John's insides, and they notice something weird. In the area where I had the tear in my intestine, there's now a fistula, which is a hole. Normally this is something you could sew right back up, but the doctors tell him, in your case... No. No.

The tissue around the area of the tear is so compromised that you can't withstand another surgery right now. Plus, you've got high level of infection again. You're no candidate for surgery. Our only solution, they tell him, is to let your gut heal on its own. But in order to do that, we've got to shut it down. Yes. Basically numb it with anesthesia. So my gut was in an induced coma.

Nothing would pass through it. There would be no activity. Which meant, the doctors told him, obviously, no eating. Instead... We're going to put you on a food pump. And the food pump is a mechanical pump about the size and the weight of two bricks. Carry it in a backpack. And the pump in the backpack is attached to this big bag.

Big bladder, the big 3,000 milliliter bag of TPN is the medical name for the nutrients. What does that stand for? Total parenteral nutrition. And the stream runs out of the pump, through the tube, into my arm. You were going to be given essentially an outdoor stomach. That's right. And this is where our story really begins. So John goes home with his new exostomach. He can't eat.

But every day around mealtime, he says, he would turn on the food pump. And this is actually what it sounds like.

So I'd start my feeding at 4 o'clock. Pump would start. I'd sit on the love seat for a while. My kids would come home from school. My wife would come home from teaching. And then the real food would come into the apartment. Sometimes neighbors brought food over. Sometimes John's wife would cook. Regardless, I was always sitting on the love seat in our living room with the food pump whirring. Like a dishwasher. While just a few feet away, his family would sit at the table. Eating fabulous food. Night after night.

This happens. And it's making me absolutely crazy. And he says, after about a week of this, and then two weeks, and then three weeks of just sitting there night after night watching his family eat dinner without him, he says he would start to drift off and get lost in these really vivid daydreams

of meals that he'd eaten in the past. One of the first memories I have is going to Katz's for the first time. Katz's is a famous Jewish jelly in Manhattan.

And standing there at the counter, where the counterman cuts the pastrami and he puts it on a plate, and he gets it out of the hot cooker and it's on a fork and he hands it to you and you take a taste. And he says in that particular instance, when he took a bite, that first bite of the pastrami sandwich, it was like pow! He said it was the first time in his life where he suddenly, he was like, oh my God, I'm Jewish. I am Jewish. These are my people.

That was the first time you felt that? It was. It was. And after about a month of no food at all and these vivid daydreams about food, something weird happened. John got hungry. Like, actually hungry. Which really doesn't make much sense because hunger signals normally travel from the gut up to the brain and his gut was numb. But he says he really started to feel hungry. It was, you know, I think of it, it was an existential hunger. And he got really bad.

For example. My wife's a terrific cook. And one night she made a little treat for the kids, mini burgers and French fries. And our small apartment smelled like the kitchen of a white castle. So my wife brought out this big plate of sliders and a pyramid and the kids were knocking down the pyramid and throwing them back. And...

I couldn't take it anymore. So I snuck out of the living room while they were preoccupied. I went into our kitchen, and there were some fries on the stovetop. And I put my hand on the fries, and I brought them up to my mouth, and I was expecting salt and oil. Fatty goodness. Fatty goodness and the texture of crunchiness and all that. I'm tasting it now. And I put it on my tongue, and I got nothing. Nothing? Really? And...

I'm rolling it around. You can't even feel it on your tongue? I mean, my tongue feels... Not even the salt? It's like when you go to the dentist and you've got Novocaine. Really? And my tongue is numb. What was going on? Was your tongue just out of practice? I couldn't figure out what was going on, and...

Then I brought up a knife. And John claims that when he looked at the reflection of his tongue in this metal knife... I see that my tongue is as flat and smooth as this Formica tabletop I've got my hand on in your studio. Oh, so you don't have the little bristly furry things? No bristles, right. And I realize I haven't used it in so long that my taste buds have evaporated. They're gone. And at the moment that that happens...

My oldest son, Teddy, who was nine at the time, comes in and he says, Dad, you're not supposed to eat. I said to him, I wasn't eating. I wasn't eating. That's like you switched places almost. And he looked at me with the most scornful, disgusted, just ashamed expression. And I was completely humiliated. I'd only failed as an eater. You had the shame flood. Right. I'd failed as a father as well.

As the weeks dragged on and John didn't get any better, he actually started to take that thought seriously. Like maybe he really was failing at being a dad. I'm a stay-at-home dad. And as a result, I'm the shopper and the cooker and the food planner and the provider for us. And I was out of commission three years out of work. With no gut. Meanwhile... I can't stop thinking about food.

And this obsession grew and grew until one night, he says, his neighbor Marsha...

for my wife and kids to eat. Walks it right past John on the way to the kitchen. And I could smell this thing. I could smell the rum. I could smell the eggs. I could smell the flour. I could smell everything. So again, he sneaks into the kitchen. And I lower my nose down to this Bundt cake and I'm smelling it and I'm sniffing it and I'm inhaling this thing like an anteater. And that's not enough in my state. So...

I plunge my hands into the chocolate cake. You what? I plunge my hands into the chocolate cake. In order to get one with the goo or what? In order to get some sensation of connection with food. Did you think, what's happening to me? Or did you think, oh, the joy? At the moment my fingers were in this cake, I felt I'm in heaven. I've reconnected with the living. I have food, if not in me, at least on me.

And at the moment where I'm experiencing most pleasure, my wife comes into the kitchen. When I went in to get the kids some more food, I found him. This, of course, is John's wife, Susan. With his hands in the cake, just trying to touch the crumbs. And he looked so guilty. And I was also like, what are you doing? What are you doing? Like somebody going through an underwear drawer. It was very, you know, wrong. And I have no explanation. I mean, I can say...

I need to do this. You have no idea how wonderful this is. Please give me some time alone with my Bundt cake. It was just, it was this bizarrely funny but deeply sad, perverse moment. Yeah. I suppose it was the first crack in my bubbled attempt to pretend things were normal. You know, I realized how bad things had gotten. And after that, she says...

Things only got worse. It just became, there was never anything to be happy about. He wasn't able to eat. He wasn't sure what the prognosis was. He wasn't sure if he was going to need a second surgery. It was just all bad. She says John became really depressed. And he became very difficult to even, not even to cheer up, but just to say, well, let's just not talk about it for now. You know, he was constantly expressing his unhappiness.

Was that the thing? It was just dark all the time? Very dark. It just became very hard to face. So she left. Well, I had spring break and my kids had spring break. So Susan took the kids to her parents' place in Indiana for a week. I needed to take a break. Not for good. Maybe the kind of break that means, I'm not really sure what our future looks like. I don't know how we're going to do this.

And I can't really figure that out while I'm with you. So I was alone. Not entirely. While I was on the food pump and not doing well. But after a few days of moping around the house, John gets an idea. What I need to get myself out of this is I need to return to a place of sanctuary for me. There was a restaurant not far from your studio here called Chanterelle.

It was a French restaurant, and it was one of these very expensive capital-letter restaurants that my wife and I had always planned to go to if we had a special occasion. For years, I walked past this restaurant, and I would look in the window before getting onto the subway, and I would see the plates of scallops coming out and the wine steward pouring red wine and the handwritten menus on the tables and things like that. So I thought, if I can get to Chanterelle,

and if I can look through the window, then I can heal myself. I'll have a reason to hope. So I got on the subway and it was past four o'clock and I was supposed to be home starting up the pump and feeding and I got off the subway and I walked over to Chanterelle and I was kind of a little dizzy and delirious and I get to the window and the dining room is empty. There's dust on the floor, the wall panels have been stripped, the tables are bare,

It's empty. It's a cave. Sometime in the intervening months, or the preceding months, rather, Chanterelle has closed. And I didn't know that. Oh, you're killing me with this story. And I think to myself, you've reached the end of the line. This is it. There's nowhere else to go. And I walk towards the river.

And I know that people throw themselves in when they do this. And it never made sense to me before. You know, I wasn't ever ready to end things. Were you really? Because I was. Were you having suicidal thoughts? I mean. I was having really depressed thoughts. And I don't know that I would have thrown myself in. But it was the first time I was standing at the edge thinking about it. Thinking about this is how these things happen. So I got to the river and I blacked out. Collapsed on the sidewalk. And I woke up and it was dark.

I'd scraped my chin and my elbows were bruised and I'd taken a hard fall. And I got up and I started to walk around. I was on this buckled old sidewalk and I looked around and there are these federal era houses and there was a grill, a gas grill in one of the backyards that was going. Somebody was cooking dinner and I could smell it. I could smell the smoke coming off the grill and I could smell it. It was pork chops.

And I was so delirious and so happy to be smelling food that I took it upon myself to finish cooking this guy's meal. Wait, what? So I... That's so eerie. I lifted up the lid. I lifted up the lid and it looked like to me, you know, one side of the pork chops were cooked and they were ready to be flipped.

So I flipped them. And I was so far gone that I thought, okay, well, four more minutes and these babies are going to be ready to go. And I didn't have a watch, so I started counting down four minutes in my head because I was going to get this stuff perfect. And all of a sudden, the back door of this townhouse opens up and a guy walks out with an apron on and a cocktail in one hand and a seasoned shaker in the other.

And he looks at me and I look very borderline. I mean, I'm rail thin. I've got it. You know, I'm cut up from having fallen on the sidewalk. I've got a crazy expression in my eyes. I haven't shaved in a week. I look really very unsavory. So he sees me and I have no way of explaining myself other than to say they're just about done.

And I hand him the tools, and I turn around, and I walk away before he has the chance to call the police or anything like that. How many years ago was this? This was now three years ago. And what do you take away from that? Was that some kind of turning point where you walk away from the grill and you're ready to fight the good fight or what? That only happens in the movies and fairy tales. What actually happened was I got sick again.

I had another infection, more bacteria, and I had to go back to the hospital. And when I went back to the hospital this time, they said, "Okay, we can't even do the food pump anymore because you keep getting these infections, and if the bacteria spreads to your bloodstream through the food pump, then you'll be gone. And we can't operate on you because you won't survive the surgery. So all we have left is to try eating."

The only thing that's left is to go back to food. Because you can't ingest it intravenously. We're afraid of infection. And we can't repair your gut surgically. So the only way you can keep yourself alive is to try to use your gut again. So they start you on a round of, I don't know, baby food? Gerber's? I did start on the traditional applesauce and jello and pudding. Soft and easily digested foods. And John says it worked.

His body was able to take the food. But I couldn't taste anything. And it continued that way for another couple of months. And did the food ever taste like food again? Well, I was at the radiologist's. This is not the scene I was expecting. Well, you know, I have a little ritual with this particular radiologist. He's on the east side.

And whenever I get tests there, when I'm done with the tests, I'm able to eat again. And again, this is when you do test prep, you're going about 24 hours without eating. So, you know, that thought of food becomes a celebration that you're going to have, right? So there's a diner on 3rd Avenue in 88.

fourth street, a fifth street that I always go to. And I get the same meal every time I sit at the counter and I get a fried egg and bacon sandwich on whole wheat toast. So I went there and I got the last seat at the counter and I ordered my usual and I chew into it. And I realized that I've got sort of embryonic flavors going on. I've got the

sort of the start of the sensation of tasting and the start of flavors in my mouth. And I could feel that great combination of the fried egg congealing with the crunchy bacon and the crunchy toast. And I do the same, you know, I've got a knife, a butter knife, and I do the same mirror knife examination at the counter. And I can see that where before it was shiny and smooth as a porpoise,

I've got little bristles. I've got little bumps on my tongue, and I can taste this fantastic $3 sandwich. Do you kiss the lady sitting next to you? Well, I turn to the guy sitting next to me, and I tell him, this is the best damn thing I've ever eaten. And in classic New York diner fashion, he looks at me. He looks up from his Kindle. He looks at me, and he says, you should try the meatloaf. LAUGHTER

And I think, you know, this is it. I'm back, baby. I'm back. Radiolab was created by Jad Abumrad and is edited by Soren Wheeler. Lulu Miller and Latif Nasser are our co-hosts. Susie Lechtenberg is our executive producer. Dylan Keefe is our director of sound design.

Our staff includes Simon Adler, Jeremy Bloom, Becca Bressler, Rachel Cusick, Akedi Foster-Keys, W. Harry Fortuna, David Gable, Maria Paz Gutierrez, Sindhu Nenesambandhan, Matt Kiyoti, Annie McEwen, Alex Neeson, Sarah Khari, Anurazkot Pas, Sarah Sandbach, Ariane Wack, Pat Walters, and Molly Webster, with help from Andrew Vinales. Our fact checkers are Diane Kelly, Emily Krieger, and Natalie Middleton. ♪

Hi, this is Tamara from Pasadena, California. Leadership support for Radiolab science programming is provided by the Gordon and Betty Moore Foundation, Science Sandbox, a Simons Foundation initiative, and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.

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