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Terry Gross
I'm Terry Gross. Here's the kind of questions my guest Mary Roach explores in her new book, what makes a pig a better organ donor than a goat? Could a heart survive indefinitely outside a body? How do you remove a deceased tissue donor's bones in a way the family will be comfortable with? Her book, titled Replaceable youe, is about the latest breakthroughs in replacing body parts from skin to hearts and prosthetic limbs. With advancements in regenerative medicine, stem cells and genetic editing, dysfunctioning parts of our bodies are replaceable in ways that were previously impossible. Mary Roach also writes about attempts to replace body parts centuries ago, including false teeth in the George Washington era and nose replacements in the 1500s. Roach is known for her books about what makes the human body so remarkable, even the parts or functions we may find embarrassing or disgusting. She's also known for making her books funny and entertaining. Mary Roach, welcome back to FRESH air. So what led you to want to write about replacing body parts?
Mary Roach
Well, for one thing, I'm 66 and things are starting to go, so it's kind of ever present in my head also, with one exception. My books have always been about the human body in some way, shape or form. And so this was kind of a logical place to go at my age. But really, one of the things that triggered it was a conversation with a reader who had contacted me with a book idea that didn't quite fit my interests. She wanted me to write about professional football referees, but it turned out in the course of emailing with her, she's an amputee, specifically an elective amputee. She's somebody who she'd had spina bifida. Her foot was twisted. She couldn't walk well. She could walk, but not well. She couldn't hike easily. And she would see people with a prosthetic lower limb walking, hiking, running. And she thought, well, I want that. But it was very difficult to find a surgeon to remove her foot because it was quote, unquote, healthy. And she would say, yeah, but I can't walk on it. And I thought that was interesting, the reluctance of the surgeons to remove a foot because it is an act with some finality to remove a foot.
Terry Gross
Well, let's stick with that for a while. You write about how amputations aren't what they used to be. It's not like the guillotine amputation. You take like a knife or some kind of blade and, like, saw off the bones. And I guess decapitate's the wrong word, but I'll use it anyways. Decapitate the limb. So what's different now? How is it done?
Mary Roach
Well, before there was anesthesia, time, time was the critical element. In other words, get it off quickly. Don't be like slowly sawing. So now it's an operation that, you know, because the person is out, it can be done carefully. And there are measures taken to try to preclude phantom limb pain. You can take nerves, the major nerves, and kind of wrap them around muscles so that they have something to do, basically. So they're not, in the words of one surgeon, a downed power line sparking in the roadway.
Terry Gross
So let me stop you. Is that why families. Phantom limb pain is caused because you have nerves that aren't attached to anything so that they're firing, so to speak. They're firing off without any reason to. And just for people who don't know what phantom limb pain is, once a limb has been amputated, your brain can still send you signals that that limb is causing you pain, right?
Mary Roach
That's right. Yeah. The thinking is that that helps preclude phantom limb pain. It's just one strategy that's taken. You can also give someone drugs in the lead up to the amputation to prevent pain, and that's thought to help as well. So there are measures one can take to kind of ward off that scenario.
Terry Gross
And, you know, in the past or the deep past, what was done was like cauterizing the wound after the amputation so that you wouldn't bleed out. How is it done now?
Mary Roach
Well, you're still cauterizing the veins. You're still doing that. You have to stop the bleeding. And then you're creating sort of a. You're folding the skin over and creating kind of a padding, a cushioning. Because if somebody's going to be using a prosthesis, you want to have something there between the bone and the socket of the prosthetic.
Terry Gross
So how's your friend doing? Does she have phantom limb pain? Does she like her prosthetic leg? Actually, she had her other leg amputated, too. So it's prosthetic legs now.
Mary Roach
Yeah, she's doing well. She was not troubled by phantom limb pain. Her surgeon did take those precautions, and she's doing well. I mean, it's been tough having the two legs amputated now, so it's. She's. But she's getting there in terms of being able to walk on them.
Terry Gross
So as a culture, one of the things we're starting to adjust to is the increasingly common use of animal parts to replace human parts. And I think one of the most common uses is the use of a pig's heart valve to replace a human's heart valve. Why pigs?
Mary Roach
Well, you can to a certain extent blame Hormel, the pork company. What happened in the 40s, 50s, 60s, there was a project that was a collaboration between the Mayo Clinic, the Mayo foundation, which was the research arm of the Mayo Clinic, and the Hormel Institute, which was the research arm of, of pork. And the goal here was to create a smaller pig, a pig that would be a good match in terms of not just the size of human organs, but the functions. All these studies were done looking at. Do pigs get coronary artery disease? And it turns out they do. In fact, the pig was described in one of their papers as a caricature of an obese human. In other words, gets heart disease, has heart issues, doesn't get enough exercise.
Terry Gross
Why are those good things? Why does that make it more compatible with a human?
Mary Roach
Well, if you're going to study, if you're going to use the pig as your model, as your stand in for a human, then you want to be sure that these organs do, that they behave similarly, that they're the similar size. So this research, once it got rolling and there were dozens and dozens of papers, three volumes of papers looking at kidney function, liver function. There was one on orthodonture where they had put braces onto pigs. So it was all toward the goal of creating an analog, a stand in for a human being for trying out surgical techniques, or not so much pharmaceuticals, but techniques and replacements. So the pig, it became the go to creature. I mean, there may be other animals. I mean, who knows? A goat might have been equally useful, but nobody started using goats.
Terry Gross
One of the big obstacles in transplanting organs, whether it's a human organ for a human being or an animal organ, is that the body rejects this foreign tissue. And the immune system thinks that this foreign tissue is like an invader that needs to be attacked. So the immune system starts attacking the organ that's saving your life. So how do they get around that? With pig transplants?
Mary Roach
Yeah. With an organ that's coming from another species, the reaction is quite severe. It's called a hyperacute rejection, where within minutes the body starts to attack the Organ starts to turn black. You don't want to put a pig organ into somebody without it having been genetically edited. So one of the things that's edited is something called the alpha gal protein. And this is a surface protein that the body. If you can knock that out, you're basically just making the pig organ seem a little less pig like and a little more human. Human like. So now you're dealing with a level of rejection that you would get with a human transplant. In other words, taking some other human's organ and transplanting it. So it's. The person is still on an immunosuppressive regimen, taking drugs to suppress the immune system, but on about the same level as they would with a human organization.
Terry Gross
If you keep kosher, like a lot of Jewish people do, you're not supposed to eat any, like, pig parts. No pork, no ham. Is a pig transplant considered kosher?
Mary Roach
I asked this. I asked the surgeon who was involved in the first pig transplant. I said, who's Muslim? And he said, yeah, there are a lot of folks, both in the Jewish religion and the Muslim religion, who really wished we'd chosen a different species. Because I had been asking him, why pigs? And he said, I get that question all the time. The thing is, he said, we're not eating them. We are saving lives. So it's okay to get a pig organ if you're keeping kosher. And this was something. There were interviews with various religious thought leaders, and there was consensus that it is indeed okay to have a pig organ implanted. Just don't eat it.
Terry Gross
So you write that the next step in terms of pig transplants is to try to grow human organs in pigs. I find that very hard to comprehend. So can you explain what the premise is?
Mary Roach
So do I. Okay, this is way off in the future, but people are starting to look at it. The term is chimerism. In other words, a chimera being part two different creatures in one. So this would be. You would take a pig blastocyst, say, just like, tiny cluster of cells, and you would edit it such that it's not gonna produce a kidney. And then you're introducing pluripotent human cells that could grow into a kidney, so that this pig would. Would literally be growing a human kidney within its body. And that kidney could then go to a person, as a human kidney would. And the pig, since it's always had that kidney, that human kidney wouldn't reject it. So that's what we're talking about. It's obviously a long way off There have Been very, very primitive, like sort of bits of a kidney that have been grown in an animal model. But this is not something coming along anytime soon. But really kind of interesting because if you go fast forward, I don't know, 100 years, the thinking would be that you could sort of have your own personal pig with a set of organs. Kind of like having a car in the backyard for spare parts. You. You would have this pig with your organs ready to go when you need them. Obviously science fiction, way, way out there, but people are working on chimerism.
Terry Gross
That's really amazing.
Mary Roach
It is, yeah. And one of the. I remember reading an ethics paper on the ethics of this, and they were saying, well, some of the cells sometimes end up in other parts of the animal's body rather than just the kidney, say. So if they land in the brain, such that the brain starts to develop more like a human brain, and the pig now starts to have human kind of awareness and intelligence. Now, do you need to treat the pig more like a human with different. Is there a moral obligation? I was like, whoa, whoa.
Terry Gross
That's a lot to wrap your head around.
Mary Roach
Yeah.
Terry Gross
So you mentioned pluripotent cells, and those are basically stem cells that can change into cells for any part of the body. And you say that pluripotent cells are the holy grail of regenerative medicine. And regenerative medicine is when you can take cells from a body and regenerate them for whatever use that you need. Can you tell us more about how pluripotent cells are being used now, what the promise is?
Mary Roach
Sure. What's exciting about this is that you can take an easily accessed cell, say, blood cells, from someone, and you can regress them to the state of pluripotency, which is where cells started out. Your cells start out just as this pluripotent entity that becomes eventually part of a kidney or part of a heart or skin. So if you can.
Terry Gross
These are cells in the fetus?
Mary Roach
Yeah, yeah, yeah. Embryo fetus, yes. When you're, let's say, a few cells old, these are pluripotent cells. And because they have this ability to become whatever. If you can get somebody's adult cells back to that stage, and then you can instruct them with enzymes, proteins, however that's done. And it's always a highly proprietary thing, you can instruct them to become something else, say a neuron that produces dopamine. Now, you could have a personalized cure for Parkinson's if you could get that to work. And that's one of the things being worked on. So in other words, you take some easily access cell, like blood cell, regress it to pluripotency, instruct it to become this kind of neuron that produces dopamine, which Parkinson's patients need. That's pretty exciting.
Terry Gross
So you're basically reverse engineering cells so they become the kinds of cells that they were in the embryonic stage.
Mary Roach
Yeah, you're regressing them to pluripotency to the. Yes. The stage where they are just basically potential and they haven't yet become what they're going to become. So if you can step in and instruct them the way the body would, then you have this amazing tool. The other thing that's kind of exciting is that if, because right now those would. It's a bespoke process, you would take the patient's cells and do all this. And it's time consuming and expensive. But if you could take, if you could create what's called a stealth pluripotent stem cell that could evade the immune system. Now you can just have off the shelf pluripotent cells that you could then give to a patient. So you're skipping the step of regressing the patient's own cells.
Terry Gross
One of the things related to what we're talking about, at least I think it's related, is attempts to regenerate hair or hair cells, hair follicles, so that you could basically take hair from one part of your body and have it grow in another part of your body. Now, I know there's already like hair transplants, but this goes beyond that. Right, Right.
Mary Roach
So this would actually not be moving it from one part of the body to the other. That's a transplant. This would be actually trying to create follicles from stem cells from the two types of basic building blocks. So again, it's like you would take someone's blood cells and regress them to pluripotency and then instruct them to. To become the two types of cells that create follicles. So it's an example of what we were talking about earlier. So you're not taking cells from the back of the head, say, and moving them as with a hair transplant.
Terry Gross
You tried it yourself? Well, you had the scientists try your hair and see if they could reproduce. I don't know what words to use. So you tell us what they did.
Mary Roach
What were you doing, Mary? Well, okay, so the company that was involved in the stem cell derived follicle project needed some follicles for study. They needed to understand what is going on in every stage of development of hair follicles. They need to, basically, because they're reverse engineering this thing. So they worked with a hair transplant surgeon nearby, Dr. Chifu, and they had. When someone was coming in to get a hair transplant, they would say, hey, would you donate some for science? And when I Was there interviewing Dr. Chifu for another chapter, the hair transplant chapter, I volunteered to donate some hair follicles. And we. While this was going on, I asked if they wouldn't mind taking some hairs from my head and transplanting them to my leg. And the reason I wanted this done, I wanted to have a living example of what's called donor dominance. And in hair transplants. This is why hair transplants work, because the hair at the sides in the back of the head are not sensitive to testosterone, like the hair on the top of the head. So you can take follicles from the back and sides, put them up at the front, at the top where the person is losing their hair, and they will now stay there and they will behave like they did on the back or the side of the head. They'll retain that golden characteristic of not falling out. So what that means you could take. And this has been done, chest hair, armpit hair, pubic hair, put it on the head and it would retain the characteristics. It would be short, kind of wiry, and quote, unquote, difficult to style. That's from a research paper. But then you could. And if you took a hair, as I did, from the back of the head and put it on the leg, it will now grow to be, you know, six, seven, eight inches long. And I thought that sounded like a really cool thing to have going on. When I'm on book tour, I could pull up my pant leg and I could go, look at this long, this luxuriant hair growing on my leg. This is donor dominance in action. And I was very excited about that. And they were, bless their hearts, willing to do this. Sadly, it didn't take. I don't have this hair to show you. Dr. Chifu was like, it's not going to work. The leg doesn't get enough blood supply compared to the head. It may not work. So he was kind of pessimistic, but I had high hopes.
Terry Gross
That would have been very strange. I'm sure it would have done very well on social media photos of that. Well, we need to take another break, so let me reintroduce you. If you're just joining us, my guest is Mary Roach. Her new book is called Replaceable youe. We'll be right back. I'm Terry Gross and this is FRESH.
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Mary Roach
Hello.
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Mary Roach
Hi, this is Molly Sivi Nesburg, digital producer at Fresh air.
Terry Gross
And this is Terry Gross, host of the show.
Mary Roach
One of the things I do is.
Terry Gross
Write the weekly newsletter, and I'm a newsletter fan. I read it every Saturday after breakfast. The newsletter includes all the week shows, staff recommendations and Molly picks timely highlights from the archive. It's a fun read.
Mary Roach
It's also the only place where we tell you what's coming up next week, an exclusive.
Terry Gross
So subscribe@whyy.org fresh air, and look for an email from Molly every Saturday morning. So one of the things that you witnessed was I think it was a hip replacement, Right.
Mary Roach
Mm.
Terry Gross
And one of the things that really surprised you during that was the anesthesia part. So at first you thought, well, the anesthesiologist is just sitting here looking at all of the, you know, numbers on the printout screen. But then you realized how important the anesthesiologist was. So describe what the anesthesiologist's job was before the surgery.
Mary Roach
Sure. In the course of my career, I think I've been in operating rooms four, five, six times and I've always come in after the patient has been completely sedated. The anesthesiologist almost to me seemed like the security guard kind of sitting there sometimes scrolling through the phone. And I thought, I guess it's Kind of a snoozer of a job. I don't know. But I met an anesthesiologist who sort of set me straight on what has to happen for a person to become intubated and anesthetized with general anesthesia. And just the intubation element is really tricky. I went to a seminar he was teaching where the fellows, they were research fellows, had to become proficient at intubation. And they were using a mannequin, like a head that has little lungs that kind of look like whoopee cushions attached. And he said, you can try it. And it's incredibly difficult because there's a lot of stuff going on inside the neck. There's the vocal cords. There's the epiglottis. There's tubes that are branching off. You know, you're e and you're breathing. Starting out with the same tube, then it's going to, you know, it's like a railroad switching yard in there. Plus, you're doing it with a time constraint. You have a couple of minutes. You got, like, four minutes before the patient would start to have brain damage. Because with general anesthesia, the patient is typically paralyzed. So that includes the diaphragm and the rib muscles. So patient's life is in your hands, and you better get that tube in there. And I was trying to. At first, I didn't get the tube. I couldn't get it in, and then I put it too far. So I was inflating only one lung and not the other. And if you started it way up higher, you'd be inflating the stomach, and the stomach could burst. And it's like. It's really tricky and scary.
Terry Gross
I didn't know that when you're under general anesthesia that you actually need to be put on a ventilator for the duration of the surgery. Is that always true, or is it just for replacements?
Mary Roach
Well, I mean, for major surgery, general anesthesia is used, but you can be put out. Like, for example, for a colonoscopy, you just have, you know, propofol. It's just you're not completely. There's different levels of sedation. I mean, for a hip replacement, like the anesthesiologist was saying, you know, we could just do an epidural, and the person could be awake, but there's a lot of hammering and sawing, and no one wants to hear that. It's also about controlling things. You know, general anesthesia. The patient is completely controlled by the machines in the operating room. And, you know, you don't Want somebody to wake up in the middle and start thrashing around?
Terry Gross
I've never seen. I want to move on to 3D printers. I have never seen a 3D printer and I've never seen the results of one. But there are experiments going on now using 3D printers for at least a phase of organ transplant. Would you explain how 3D printers are being experimented with now?
Mary Roach
Sure. I spent a day at the Feinberg lab at Carnegie Mellon in Pittsburgh, and what people were working on there was trying to print muscle in a way that the alignment of the cells would create muscle that had the specific function that muscle needed. In other words, a heart. The heart needs to move in a kind of a twisting motion. It twists as it pumps. So you've got to print the cells kind of. They have to be in a helix shape, which is different from, say, the hamstring would be kind of parallel. Or the shoulder muscle, they're in a kind of a fan like shape, which gives you a lot of the versatility of the movement of the shoulder so that you're not just printing generic muscle. You have to print it in a very specific way to achieve the function that you want it to be doing, which I found kind of amazing. And no one is printing whole organs. That's way off in the future. But one of the people there had managed to print a single ventricle that was pumping in a mouse, which was. I mean, it doesn't sound like much.
Terry Gross
And the mouse is amazing.
Mary Roach
It is pretty amazing. She said, though, because I said, oh, my God, you've got a ventricle pumping, keeping a mouse alive. She goes, whoa, whoa, whoa. The mouse still has his heart, but the blood is going through. And soon they're going to install. They had printed tri leaflet valves that worked properly, which is amazing. You know, it's so hard to do. You also have to think about, you know, if you're going to print something, tissue, it has to be fed. So how are you going to do that? Are you going to print the individual capillaries? No, you're going to hopefully let the body grow its own capillaries. The science is kind of at the point of trying to figure out how much do we have to print and how much can we let the body do? So if you can let the body do it, that's great. When we get fatter, we grow capillaries to serve the fat. So the body will do a bit of it, but it's not going to instantly create an aorta or something.
Terry Gross
Well, one of the researchers said to you, muscle needs nerves also, because without nerves, basically it's meat.
Mary Roach
Right? Right. And no one is printing nerves yet. So that's another piece of the puzzle.
Terry Gross
Still, it's just amazing the things that are in the works now. I'm wondering if a lot of the research facilities doing research in like regenerating cells and pluripotent cells and, you know, trying to figure out better, more effective ways of replacing organs. I wonder if they're losing their funding as a result of all of the funding that was cut during the Trump administration.
Mary Roach
Yeah. This book started to go into production right around the time that Doge got busy. And one of the things I wanted to do for the epilogue of the book is to get back in touch with people and say, what is going on? Are your projects being cut? Is your funding getting cut? And they were at the phase where they were like, we are all terrified. We don't yet know what's coming. We don't even know. There are some projects, you know, 10 year contracts for grants that even though it's a signed contract, they were like, this could be terminated, which is unthinkable. I mean, all of the work that's gone into that and the patients that will benefit, it's potentially devastating. And I don't know exactly who's had what cut, but I know that some of the folks who were graduate students and they were about to head out on their careers and they're looking at options in other countries. So the whole pipeline of innovation and discovery is kind of getting interrupted and that's going to have terrible effects farther down the line. I mean, not setting aside the projects that are underway and the patients that will benefit, just looking forward to the future of innovation and medical care. It's very depressing.
Terry Gross
We need to take another break here, so I'm going to reintroduce you. My guest is Mary Roach and her new book is called Replaceable youe. We'll be right back. This is FRESH air.
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Is this National Public Radio? Sort of.
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Terry Gross
I want to talk with you about organ donation. I know in Pennsylvania, and I'm not sure if this is true of every state, when you renew your driver's license or registration, I forget which, you have to check if you want to be an organ donor. And you did some research on organ donation. What did you learn about donating organs, including skin, after you were declared legally dead?
Mary Roach
Well, I looked into mostly tissue donation.
Terry Gross
Why did you focus on that?
Mary Roach
Because in another one of my books, I had covered organ transplantation and I felt like I was repeating myself. And I had always been interested in the tissue donation element of it because when I wrote Stiff, I could never get access to a tissue recovery.
Terry Gross
Stiff was about cadavers.
Mary Roach
Yeah. About kind of postmortem careers, cadaver research. So I had been to an organ recovery for that book. So I wanted to focus on something different, tissue recovery. In other words, bones, ligaments, skin, corneas, all of the other material in a body which can be used and be helpful for patients. And I was curious about that process. How do you remove these things and then, you know, have a body that can still have an open casket funeral?
Terry Gross
So I want to paraphrase something you say in the book and talking about tissue recovery in cadaver labs is you say you were expecting something resembling the Jeffrey Dahmer story, but instead it was closer to ups. What made you say that?
Mary Roach
I said that because when I arrived in the room where they were doing the tissue recovery, where they would be extracting the bone and the tendon and the skin, et cetera, one of the people doing it said to me, this is the worst part of the job. And I had preconceived notions of what the worst part of that job might be. But she was talking about handwriting on labels, the same ID number over and over, double checking, cross checking, the amount of paperwork and labeling. And then at the end, packing and shipping was the tedious and unpleasant part of her job, not the opening up of a leg and the extracting of bone or ligament. I guess I just wasn't expecting that.
Terry Gross
You mentioned at the beginning of the interview that you're getting older and you feel like parts of your body are wearing out. And I'm wondering how the kind of books that you write that are so explicit about body functions and about research into how the body works and this new book about new ways of like replacing organs, does that change your relationship to your own body? Does it make you more self conscious about being in a body or has it made you more comfortable with your body?
Mary Roach
I like knowing more about what's going on in my body and for the most part it makes me appreciative, I guess. Like I remember learning about stretch receptors and how you have these, you know, in the intestinal tract, in the rectum particular, they've got these receptors that know when this organ is stretching and filling and let your brain know. And I was like, that's how it works. So cool. So I am constantly marveling at all of this stuff going on in the background of myself. I think that I'm. I'm unpleasant to be around. If you're at all squeamish, why squeamish? Well, okay. My husband is a very squeamish man, particularly as regards the eye. And I was reading this old booklet about the operation of couching where they press the lens down into the lower part of the eye and he's like, ixnay on the ouchin k. No, people aren't like me always. So sometimes I can't sort of share my appreciation for all these gooey bits and pieces of us that are performing miracles on a daily basis.
Terry Gross
There are some things that the body does, as you put it in the background, and it's probably a good idea not to be too conscious of it. And I'm thinking of like digestion, what the large intestine is doing, what's passing through it, breathing. Unless you're meditating or something, or you have breathing problems, if you're too conscious about your breathing, without that consciousness having some kind of function, it can be very distracting. It's best probably if you just do it. And there's all kinds of things. If you focus on it too much, it's easy to start worrying about it.
Mary Roach
Yes, there's something called heart awareness where you become too aware of your heartbeat and what it's doing. And I think that creates anxiety. And then your heart does start doing weird. I think, yes, it's not necessarily helpful to be tuned into all this. And I don't think that I am. I'm trying to think of an instance where I feel like I know too much. I know when I worked on Gulp.
Terry Gross
About the digestive system, about everything between.
Mary Roach
The nose and the butt, the weird tube with all the bacteria and everything, I became really aware of what's going on in your mouth when you chew. The process of bolus formation where you're taking a piece of meat, say, and you're breaking it down and then you're putting it back together in a bolus. That's a shape that can slide down the throat. And I visited somebody who studies chewing and this process and what the jaws do. And I remember for a while after that going to restaurants and thinking, looking around and at people chewing and swallowing and thinking, this is disgusting. Like people. People should have sex in public and eat in private. It's absolutely disgusting.
Terry Gross
One more question. There's a French expression, belle lad. I'm not sure exactly how to pronounce it, but it basically means beautiful, ugly, which is, I think, a good way of describing a lot of parts of the body. There's something really ugly and weird looking about some of the parts, the internal parts that we don't see. But there's something really magnificent and beautiful about it, too. Do you feel that way about parts of the insides that we don't get.
Mary Roach
To see very much? So, I mean, if you ever see a liver. Well, you've seen a. I mean, no.
Terry Gross
I haven't seen a liver. I've seen a chicken liver, a beef.
Mary Roach
Liver, say, oh, I've seen that. It's kind of a glistening, streamlined, kind of beautiful object. It's not creepy, I don't think. And a heart. Hearts are surprising. Like, if you see a heart inside somebody's chest beating, and I saw this on an organ recovery. It's surprisingly active. I mean, you think from your own heart, heartbeat, that it's sort of a very gentle kind of motion. But that thing's like squirming around in there in this little space. It's kind of extraordinary. And it's doing that over and over and over and over for like, if you're lucky, 80, 90, 100 years. And it keeps on going. And like, what thing that you buy at Best Buy keeps going that long?
Terry Gross
It's the kind of thing I try not to think about a lot.
Mary Roach
Don't think about it. Just don't. Just let it do its thing and don't think about it.
Terry Gross
Yeah, yeah, yeah. Mary Roach, thank you so much for talking with us. It's always a pleasure to have you on the show.
Mary Roach
Thank you so much, Terry. Always a joy.
Terry Gross
Mary Roach is the author of the new book Replaceable youe. Coming up, an excerpt of an interview with me. I'll explain after a break. This is FRESH air, Sources and Methods.
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Terry Gross
This month marks my 50th anniversary hosting the show. Is that long enough to get me in the Guinness Book of Records? We're fact checking that right now. When I started hosting in 1975, fresh air was a local show, three hours a day, five days a week, heard only by listeners to WHYY in Philadelphia. We didn't become a daily NPR show until 1987. In recognition of my anniversary, I was invited to be a guest on a podcast that I like a lot called Talk Easy, hosted by a terrific interviewer, Sam Fragoso. In a special collaboration between Fresh Air and Talk Easy, my interview with Sam, or I should say his interview with me, is now available on both podcast feeds. To give you some sense of what it's like, we're sharing a short excerpt. It comes in a part of the interview about my upbringing in Brooklyn. One of my answers was kind of embarrassing. You'll know when you get to it, because I preface the answer with I'm too embarrassed to reveal that. So here it is, a preview of my interview on Talk Easy with Sam Fragoso.
Podcast Hosts (Ian and Mike)
You said once that you were, quote, brought up believing that there's some positive value in thinking negatively.
Terry Gross
Oh, yes. I think it's a very Kinahara Jewish thing. If you think something is gonna turn out badly, then you won't be disappointed when it turns out badly Sounds a.
Podcast Hosts (Ian and Mike)
Little bit like a Mel Brooks quote.
Terry Gross
Hope for the best, expect the worst is a quote. It's a quote from one of his lyrics. And that's like, when asked, do you have a motto? That's what I always do.
Podcast Hosts (Ian and Mike)
That's your motto.
Terry Gross
But also it was like, if you expect good things to happen, they're not gonna. You know, it went along with my father's, you know, expression. No one ever said life was about pleasure. You know, like weekends you get some time off where you're allotted a certain amount of pleasure, but during the week.
Podcast Hosts (Ian and Mike)
It'S like, what was your mother's motto?
Terry Gross
She didn't really have one.
Podcast Hosts (Ian and Mike)
Yeah, most people don't have mottos.
Terry Gross
Yeah, I mean, it wasn't literally his motto, but. But it's something that I heard and certainly that I probably internalized.
Podcast Hosts (Ian and Mike)
Taking this maybe too literally, but what did that inner monologue of thinking negatively sound like for a young Terry Gross?
Terry Gross
Frustrating. A little annoying, but I think I internalized it anyway.
Podcast Hosts (Ian and Mike)
What part was frustrating?
Terry Gross
Well, you want some time for pleasure. And like, when I was a little child, this was more when I was a teenager.
Podcast Hosts (Ian and Mike)
Right.
Terry Gross
When I was a teenager, I was still a really good student, doing really well in school, but hanging out. I wouldn't exactly call myself a theater kid, but we had something called sing in Brooklyn schools where you write a long sketch, take Broadway melodies, and write lyrics to those melodies. So I was one of the lyricists.
Podcast Hosts (Ian and Mike)
For all four years. You were one of the lyricists, right?
Terry Gross
For at least three of them. But anyways, yeah, I want a pleasure.
Podcast Hosts (Ian and Mike)
In my life being a lyricist. Sounds pleasurable.
Terry Gross
Oh, it was. It was great. I loved it.
Podcast Hosts (Ian and Mike)
When you were writing those songs in high school, it's my understanding that you once overheard basketball players sing your lyrics. Now you remember what those lyrics are, don't you?
Terry Gross
I'm too embarrassed to reveal them.
Podcast Hosts (Ian and Mike)
Hold on. You've said in the past that you won't say them. What if we sang them together?
Terry Gross
We're not gonna do that. There's no way we're gonna do that. You don't even know the lyrics.
Podcast Hosts (Ian and Mike)
Well, that's why if you teach me, just give me. Imagine yourself as Stephen Sondheim. Give me one line.
Terry Gross
Okay, I may live to regret this.
Podcast Hosts (Ian and Mike)
That was the alternate title of your book, right?
Terry Gross
The alternate title of a lot of my life. Okay, so the premise is kind of like a ripoff of how to succeed in business without really trying, where the main character finds, like, a rule book for success, like a self help book for Success called how to succeed in business without really trying. We kind of used the same premise. And the premise was that we wanted to be like cool and we didn't know how to be cool. We needed a handbook.
Podcast Hosts (Ian and Mike)
I wish I had that in high school.
Terry Gross
Or that we were going to create the handbook. I think we needed the handbook. And so the melody was to l' Chaim from Fiddler on the Roof. And the opening lyric was, the book will be our mentor, our noteworthy source of the rules. It will teach us explicitly, in sheer simplicity, step by step, to be cool. The school will marvel at how cool and groovy we look. They won't suspect that the gimmick is that we are mimickers of a 16 page book or something like 60 page book.
Podcast Hosts (Ian and Mike)
Excellent.
Terry Gross
I'm done.
Podcast Hosts (Ian and Mike)
Excellent.
Terry Gross
I'm totally done with the interview. No, no, I'm not gonna pull a mammoth.
Podcast Hosts (Ian and Mike)
Or a Bill O'Reilly or Bill.
Terry Gross
O'Reilly or several other people. I can say Cora Faye Dunaway or.
Podcast Hosts (Ian and Mike)
Faye Dunaway or Monica Lewinsky or Monica or Lou Reed. After six minutes in 1996.
Terry Gross
Yes, I can.
Podcast Hosts (Ian and Mike)
Keep going. Of Fresh AIR walkouts.
Terry Gross
It's an illustrious roster.
Podcast Hosts (Ian and Mike)
I have to say, it's a really great roster. That was fantastic.
Terry Gross
Listen, if I really live to regret it, you're going to know about it.
Podcast Hosts (Ian and Mike)
I believe it and as will our listeners. That was amazing.
Terry Gross
I don't hear the compliments. I don't wanna hear.
Podcast Hosts (Ian and Mike)
Like I said, that was amazing.
Terry Gross
No, you think it's amazing that I revealed it.
Podcast Hosts (Ian and Mike)
Yeah, you're right. You caught me on that.
Terry Gross
I know.
Podcast Hosts (Ian and Mike)
When you were sharing the lyrics, I was like, God, how am I gonna remember to sing all these? This is, of course, this is very long. Was it satisfying to hear your fellow classmates singing your words?
Terry Gross
Oh, it was great. I felt so affirmed. Cause I wasn't in with like the basketball crowd, even though I was what was called a booster, not a cheerle, but somebody who just kind of screamed loud and got to wear like a special jacket with the team's name on it. But I didn't really know the guys and they were like the cool guys in school. So a couple of those guys singing a lyric that I'd written that was like, whoa. That was an excerpt of my interview on Talk Easy with Sam Fragoso. You can find this episode in the Fresh Air podcast feed as a special extra episode. And of course, you can also find it on the Talk Easy podcast and online@talkeasypod.com A video version of this interview will be on YouTube later this week. Tomorrow on FRESH AIR, we'll talk about how Charlie Kirk became a leader of the conservative youth movement and a close associate of President Trump and Don Jr. We'll talk with Robert Draper, who wrote a profile of Kirk in the New York Times Magazine earlier this year, stayed in touch with him and continued writing about him. Draper covers the political dynamics of the right. I hope you'll join us to keep up with what's on the show and get highlights of our interviews. Follow us on Instagram P R FRESH air Fresh Air's executive producer is Danny Miller. Our technical director and engineer is Audrey Bentham. Our managing producer is Sam Brigger. Our interviews and reviews are produced and edited by Phyllis Myers, Roberta Shorrock, Annre Boldonado, Lauren Krenzel, Teresa Madden, Monique Nazareth, Susan Yakundi and Anna Bauman. Our digital media producer is Molly Sivi Nesper. Our consulting visual producer is Hope Wilson. Thaya Challoner directed today's show. Our co host is Tanya Moseley. I'm Terry Gross. Hi, it's Terry Gross with a deal to propose a way to help you and Fresh Air. If you sign up for Fresh Air plus, you'll get bonus content and daily Fresh Air episodes without ads. You'll also be supporting Fresh Air and public media. Learn more and sign up@plus.npr.org hey, it's Rachel Martin.
Mary Roach
I'm the host of Wildcard from npr. For a lot of my years as.
NPR Announcer
A radio host, silence sort of made me nervous.
Mary Roach
That pause before an answer because you don't know what's going on on the other side of the mic.
NPR Announcer
But these days, I love it.
Terry Gross
Gosh. Whoa, give me a minute.
Mary Roach
Yeah, yeah. Think.
Terry Gross
Listen to the Wild Card podcast only from npr.
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What's made you happy as of late? On Pop Culture Happy Hour, we've been talking about the things that have made us happy in the pop culture universe for the past 15 years. Whether it's a blockbuster or deliciously bad reality TV, the newest shows, dramas and reboots. We're here to keep your spirits high. Listen to Pop Culture Happy Hour on the NPR app or wherever you get your podcasts.
Date: September 16, 2025
Host: Terry Gross
Guest: Mary Roach, science writer, author of "Replaceable Youe"
In this engaging and often witty conversation, Terry Gross interviews celebrated science writer Mary Roach about her new book, Replaceable Youe. Their discussion dives deep into the fascinating world of medical advances that enable us to repair, regenerate, or entirely replace failing human body parts. Roach, renowned for her humor and curiosity about the human body, unpacks the science and the stories behind amputations, prosthetics, animal-to-human transplants, regenerative medicine, stem cell breakthroughs, and even the historical quirks of organ replacement efforts. The episode also explores the ethics, cultural dilemmas, and emotional complexities involved in this rapidly evolving field.
Evolution of Procedures
Improved Outcomes & Patient Stories
Why Pigs?
Overcoming Organ Rejection
Religious/Cultural Considerations
The Sci-Fi of Tomorrow
Ethical Quandaries
Pluripotent Cells—The "Holy Grail"
Future Prospects
Science Literacy and Squeamishness
Too Much Awareness?
Beauty in the Bizarre
On Pig Organs:
"We're not eating them. We are saving lives."
— Surgeon quoted by Mary Roach [09:51]
On Hypothetical 'Personal Organ Pigs':
"You could sort of have your own personal pig with a set of organs. Kind of like having a car in the backyard for spare parts."
— Mary Roach [11:33]
On Heart Transplants:
"Hearts are surprising...It's kind of extraordinary. And it's doing that over and over and over and over...what thing that you buy at Best Buy keeps going that long?"
— Mary Roach [39:22]
On Medical Funding Cuts:
"...The whole pipeline of innovation and discovery is kind of getting interrupted and that's going to have terrible effects farther down the line."
— Mary Roach [30:47]
On Personal Squeamishness:
"People should have sex in public and eat in private. It's absolutely disgusting."
— Mary Roach, reflecting on watching people chew after writing Gulp [38:19]
The episode blends Mary Roach’s hallmark curiosity and irreverent humor with Terry Gross’s probing, empathetic interview style. Roach intersperses scientific details with anecdotes and analogies that demystify complex procedures while keeping the conversation lively, self-deprecating, and often laugh-out-loud funny.
This summary covers all significant topics from the conversation, capturing both the technical depth and the quirky warmth that make Mary Roach’s work—and this interview—a delight for listeners interested in the wonders (and weirdness) of the human body.