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OUTLINE:
0:00 - Introduction
1:06 - Hands
10:21 - Sex
20:01 - Future of medicine
29:08 - Throat
39:32 - Heart and blood
47:34 - Genitals
1:00:02 - Poop
1:04:18 - Emergency room
1:12:09 - Sperm
1:17:14 - Liver
1:22:43 - Living in the Far North
1:41:27 - War and medicine
1:46:13 - Antarctica
1:59:09 - Artificial organs
2:07:45 - History of medicine
2:16:45 - Paul Farmer
2:21:11 - Advice for young people
2:28:08 - Struggle
2:34:13 - Mortality
2:39:49 - Meaning of life

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We have 2 tubes that are right next to each other in the throat.

1 is for food, drink, saliva, mucus, snot, whatever you're going to swallow.

All of that stuff must go down the esophagus, the food tube, and end up in the stomach.

And right next to the esophagus, millimeters away, is the windpipe or the trachea, which goes down to the lungs.

Every organ from moment to moment keeps us alive and ensures our survival.

How would you improve the penis and the vagina?

The following is a conversation with Jonathan Reisman, a physician and writer of The Unseen Body, a doctor's journey through the hidden wonders of human anatomy.

He has practiced medicine in some of the world's most remote places, including the Alaskan and Russian Arctic, Antarctica, and the Himalayan mountains of Nepal.

To support it, please Check out our sponsors in the description.

And now, dear friends, here's Jonathan Reisman.

You wrote a book called Unseen Body, all about the human body, the messy, the weird, the beautiful, and the fascinating details.

So, from an evolutionary perspective, are most parts of the human body a feature or a bug?

Is it like the optimal solution or just a duct tape solution?

I think that most of the time, the way the body works is the best solution.

I haven't seen many alternatives so it's hard to compare, but I think you know there's some parts of the body that make more sense than others.

You know the way our hands work for instance, you know the muscles are up in the forearm and on the tendons kind of come down like strings on a puppet.

And just the dexterity it gives our hands is just really amazing, and it's hard to imagine a better tool than the human hand to do everything from, you know, hold things to play piano and do a million other daily activities that we do.

1 thing I talk about in the book, there's some other body parts that seem to be lacking that kind of brilliant design such as the throat, you know, where the food, drink are swallowed and air is inhaled and they kind of, those 2 paths come within millimeters of each other.

And you slip up once, you laugh while eating, or you speak while trying to swallow, and you die from choking.

So it seems less than optimal, though I'm not sure it could be better from the way we're kind of formed in the womb as a beginning as this tiny little tube.

I don't think it could have been done any better or there's any other way to do it, but it is an unfortunate thing that does lead to some problems.

So the hand, if I could just linger on that for a second.

You talk about the wisdom of a design in the book.

What are the important things about the hand?

It seems like very useful for many things and it seems to be quite effective.

A lot of people think the thumb is foundational to the human civilization.

I think that is true actually 1 of the ways in which the importance of individual fingers comes To attention is when people have severe injuries to their fingers for instance I have a story in the book about a guy whose thumb is nearly ripped off by his dog's leash.

And when plastic surgeons, who are often the ones to repair that, sometimes it's orthopedic surgeons, they will debate how important is it to save this finger or how important is it to save, let's say, the tip, the tip one-third of 1 of your fingers.

It depends on the length that you'll lose, it depends on which finger.

And So the thumb really is the most crucial, just for your occupation in most cases, to just daily life and your ability to get around and take care of yourself and others.

So they'll be more, they're willing to go further, do more surgeries, more aggressive therapy to save a thumb, let's say, than the tip of your pinky finger.

So in that way, I do think the thumb does seem like the most important in many ways.

I wonder if that's part of the feature, or is it just the symmetry that nature produces?

You think the 2 hands is like, is it about the symmetry or is it about backup?

We'd be much less formidable hunters, gatherers, survivors in any way if we only had 1 hand.

So I think that is important to have 2 so we can, you know, even everything from kind of spearing an animal to firing a bow and arrow to butchering an animal, you really need 2 hands to do it very effectively.

You tweeted, now I'm gonna analyze your tweets, like it's Shakespeare sometimes.

You tweeted that, quote, millions of years of sex and death design the human body.

Are those 2 basic activities basically summarize everything that resulted in humans on Earth?

So like, is that a good summary of the evolutionary process that led to this conscious, intelligent being?

So sex is how more of us get made, obviously.

And death is how we get weeded out, or the gene pool gets weeded out and certain genes survive and others don't.

And the age at which we die, whether it's before we've had sex and reproduced ourselves, is a big factor in who survives, who doesn't, who passes on their genes, and what the future of the body looks like.

Who lived and who died before they were able to be at reproductive age a million years ago was pretty important in what we look like now.

And perhaps how we have sex and die now will determine what we're shaped like, unless technology has an even bigger role in that, you know, a million years from now.

So you think that's fundamental to like, if there's alien civilizations out there that have the same order of magnitude of intelligence or greater, do you think that we will see something like sex and something like death?

So the reproducing and this selection process, plus the weeding out of the old to make room for the new?

I mean it sure seems to be on earth, you know, perhaps in some distant future when medicine is nearing, you know, perfection and people can live a really long time, maybe we won't even need to reproduce as much or something like that.

It's hard to even know what life will be like in the distant future, but I would guess that any alien civilization will have the same dependence on who has sex and who dies.

Well, that's the problem with immortality, how are we going to clear out the old to make room for the new, which is kind of a, it's like a framework of adaptability to changing environments.

So as long as the environment is changing, and it seems to always be, because the entirety of the Earth system is a complex system, it seems like you have to adapt, and to adapt you have to kill off the stubborn old ideas.

And unless there's a way to not become stubborn and old, but it feels like the nature of wisdom is stubborn and old.

It's like the lessons of life, the lessons of experience solidified.

And the solidification is the thing that actually prevents you from reinventing yourself to adapt to the new changing conditions.

But then again, why not have both of those modes?

1 immortal person that, like, in the morning, they act like a teenager, in the evening, they act like an old wise man.

So you see, you can imagine within 1 mind both modes, but those are required.

You have to have the ability to completely reinvent yourself, which is what death does in an ugly way or a beautiful way, depending on your perspective, depending whether you take the human perspective or the nature's perspective, and then you have to have the selection, so competition, so sexual selection.

It's an interesting little planet we got.

What's the weirdest part, function, concept, idea about the human body to you?

We'll talk about fascinating details, but what's, you, I should say, for people that should read your book, they will come face to face with the fact that you do not shy away from the weird and the wonderful of the human body.

So given that, Sorry to make you pick 1 of your children, but what's the weirdest 1, would you say?

So the chapters, you divide it up kind of into parts, but there could be a thread that connects all of them, the weirdness, maybe, or maybe the texture of the substance, could be the liquids, the solids, I don't know.

Definitely every body part and bodily fluid has their own kind of both gross and fascinating aspects.

That's probably why I'm a generalist as a doctor and couldn't just, as you said, pick 1 of my children, become a specialist, because I like them all.

I feel like 1 of the strangest concepts about the human body is that kind of the aspects of it that are the most universal that we all do are the most taboo socially.

I wouldn't have expected that if I had, you know, just looked from the outside, like what we do in the bathroom, what we do in the bedroom, what we do to our own genitals, what we do to our, you know, quote-unquote private parts, they're private, even though it's sort of the thing that we have all have in common, is the most we try to hide from other people and don't talk about in polite company.

I mean it makes sense as a human living in this society, but from the outside, it sort of might be surprising.

How do you make sense of that if you put on your Sigmund Freud hat?

The thing we all do, why do we make that a taboo thing?

Maybe we get off, or maybe our kinks as humans is to have taboos, and it's kind of efficient to have taboos about the things that everybody does.

something, I don't know, but just maybe that's what we love, that's what's exciting to us, is the forbidden.

I think, yes, society loves rules for sure.

They love some societies more than others.

They love controlling how you think and what you do in public versus in private.

You know, there's a lot of societies where, for instance, parents have sex in front of children.

Not, you know, for instance, like in a traditional Inupiat Eskimo society, is that was sort of normal.

I mean, but what are you gonna do, go outside in the middle of the winter in the Arctic and do it out there of course not so You know, there's different Different taboos in different societies.

Some taboos are Even public health measures, you know, like as I talk in the book about in in India where they you know, the hands are symmetric as you said, but in Indian culture, the left hand is taboo, and the right hand is what you use for shaking hands, for eating, for other things, and the left hand is the dirty hand that you use for wiping your own bottom.

You know, that's the toilet paper is your left hand.

So while the body is anatomically symmetric, the taboo creates this pretty intense asymmetry.

But for a good reason, you know, yet you probably shouldn't be shaking hands with other people with the same hand that you use to kinda clean your bottom.

but the way it propagates, especially as the times change, might not, because you can wash your hands, but the taboo remains.

What is the most fascinating part, function, or concept in the human body?

I guess the most obvious 1 is the brain, partly because it's so, you know, sort of poorly understood, though we understand more than we ever have in the past.

There's still so much that we don't understand about how the lump of matter in our skulls kind of creates this subjective experience that we all kind of understand quite viscerally.

I would say the kidneys are an underappreciated organ.

The way they tinker with the bloodstream, raise levels of this, lower levels of that, kind of our entire lives from inside the womb until we die is just really incredible.

And when you look at how much energy different organs consume, the brain and the kidneys are 2 of the biggest ones because the brain obviously in us is always active and controlling parts of the body, but the kidneys are just consuming a ton of energy to do what they do.

They're kind of the unsung hero of the body, relegated to the back of the abdomen, like some forgotten organ, but they are great.

I did consider being a nephrologist, which is a kidney specialist, because I was so taken with the kidneys, but decided I like all the organs, so couldn't pick just 1.

So your book is ordered in a particular way.

It's throat, heart, feces, genitals, liver, pineal gland, brain, skin, urine, fat, lungs, eyes, mucus, fingers and toes, and blood.

All right, first of all, great, great chapter titles.

Is there a reason for this ordering or is it all madness?

There's a few different reasons that went into it.

I did wanna start with the throat for the reason that it kind of presents the topic of death, which is sort of obviously very important in the training of a physician, in the career of a physician.

You know, on the first day of medical school, we started the dissection of a cadaver in the class called anatomy lab.

And so in a way, we were kind of thrown right in there in the beginning, like this is the end of the human story, you know, understand this.

And then we sort of backed up to the beginning with embryology and reproduction and stuff.

So it was kind of like we got, and I got thrown into that right away, right in the beginning, kind of like, here's a dead body, now start cutting it apart and learn the name and function of absolutely every bit of flesh.

How did that change you, that first experience with the cold honesty of human biology?

Right, that's exactly what it was, this cold honesty about the kind of the story of each individual human body.

I think that, well, actually before the end of that first day, so what we did on that first day was study the superficial muscles of the back, like the lats or latissimus dorsi and some other muscles.

You know, we cut through the skin of the back.

My cadaver was laying face down on this metal gurney.

We pulled back the kind of plastic sheets that would keep him moist for the next 4 months as we dissected him, cut through the skin on his back, and then started dissecting through the superficial muscles of the back.

And that was really all we saw that first day.

We didn't get any deeper, didn't enter the abdominal or chest cavity to see internal organs, but I was so fascinated with this sort of behind the scenes look at how things work in the body, how you move your arms, how you arch your back, you know, these are the muscles that do it, that I decided I wanted to donate my own body for the same purpose.

So I made that decision literally before the end of that first day of class, and I'm still sticking to it.

So someday there'll be a medical student that can watch and listen to this podcast while dissecting your body.

They might not know that that person they're listening to on the podcast will be the carcass in front of them.

And they will acknowledge the irony or the humor, the absurdity of that.

The universe will chuckle, but the medical student won't know because they never, as I did not, learn any personal information about the person.

Only what I could glean from looking inside him, which actually tells you quite a bit.

I knew he was a smoker, I knew he had coronary artery disease.

You get a window into, I knew he was overweight, you get a window into people's lives just by looking in their bodies after death.

Other cadavers in the lab, not my own, or I shared 1 with 3 other students, but other cadavers, some had metal joints, like a knee replacement, some had a kidney missing, so they probably, and we could tell it was surgically removed, not that he was born with 1, and we could tell that he probably had a kidney tumor or cancer that was removed.

So you do get an insight into people's lives from picking them apart after they're dead, but you don't know their name or what podcast they've been on.

So as the book title says, Unseen Body, so it tells some kind of story of your life.

So it does capture the decisions you've made in your life, the things you've done, that might be kind of secret to that person and maybe to a few others that knew him or her well.

Like what kind of choices in terms of the injuries, the catastrophic events, the lifestyle choices of smoking and diet and all those kinds of things, what can you see, What kind of history can you see about the human before you?

So all those things you mentioned are things you can see.

You can, you know, take the skin for example, right?

Most things that happen to us leave a mark.

You know, as I say, kind of a story written in the language of scar, where it tells you injuries you've had.

You know, I've seen deer hides that have marks that look like they're made by maybe a barbed wire fence, something like that.

You can tell, you know, sometimes it's conjecture, but you can sort of imagine what might have happened to cause that.

Perhaps, you know, 2 bucks were fighting and 1 got injured with an antler.

And the same with humans, you know, I have scars on my body and when I notice them I remember what happened.

I got a big cut on my hand when I was 13 and it's still there and I remember what happened every time I look at it.

And so in that way, only I might know that story, but other people, when they dissect me and notice the same scars, they can kind of, it can fire their imagination as my cadaver did for me.

That's such an interesting way that the skin does tell a story, both tattoos and scars.

And some of the fun you've had and some of the damage you've done.

And even when I evaluate a patient, I can use scars to help me make medical decisions.

So for instance, someone that comes in with abdominal pain into the emergency room, you can see scars on their abdomen that tell you about, you know, the past kind of activities of a surgeon perhaps.

I know, I recognize the scars that are left when someone has their gallbladder removed, the scars when someone has their appendix removed, when maybe when someone's had a hysterectomy, and that can tell you what it might be or what it isn't, you know.

If someone doesn't have an appendix, their abdominal pain is not a bendicitis, end of story.

So in that way, I'm sort of looking at these, the tracks or the footprints of past surgeries to tell me what might and might not be the cause of this patient's abdominal pain, which is kind of my main job in the ER is figuring out what's causing it and to help them.

Is there ways to get more data about the human body as we look into the future of medicine, biology, that would be helpful to fill in some of the gaps of the story?

So You have companies, you have research that looks at collection of blood over long periods of time to see sort of, paint a picture of what's happening in your body, mostly to help with lifestyle decisions, but also to anticipate things that can go wrong and all that kind of stuff.

Is there, can you just speak to a greater digital world that we're stepping in, how that can help tell a richer story?

I certainly think that we have more data than we know what to do with right now, especially with kind of direct-to-consumer medical devices, you know, smartwatches, etc., that are just collecting these reams of data.

I have not seen them put to, I think, the eventual use that they will, I think that the potential is sort of just unimaginable.

And I hope we're heading into a new age where you can determine, for instance, is a person going to have more of the dangerous side effects to a drug based on their genetics?

Or are they gonna tolerate 1 drug better than the other based on their genetics?

And we are slowly moving into that age, and especially the age of kind of completely synthesizing drugs in the lab, much like, for instance, some of the COVID vaccines, actually, like Moderna never had the virus in their lab.

They made that vaccine completely without ever having the virus themselves, just by having the genome, which is sort of astounding.

And there's a lot of potential going forward, you know, based on that technology and some others.

So they basically it's all in the computer, it's computational.

Right, you have the genetic code, you have tremendous power even if you don't have the organism itself.

you make of Elizabeth Holmes and efforts like that?

First of all, I'm a curious, I'm drawn to the darkness in human nature because that somehow reveals the full spectrum of what humans could be.

So there's a lot of sort of controversial thoughts about who she is and her efforts and so on.

I think you may have even tweeted about it, but I've read a lot of your tweets so I'm now forgetting.

But what do you make of her and those efforts, both those efforts and the charlatans that sort of snake oil salesmen that promise those efforts to do more than they currently can?

you know that goal that she had that she created Theranos to try to achieve to use less blood in tests is a very worthy goal and a huge frontier that we have not achieved and that I hope we will achieve.

So I understand why, you know, someone describes what a huge step forward that would be, and it would be indeed.

I understand why people put a ton of money behind it.

What are we even talking about with Theranos?

So Theranos is a company that was basically started to revolutionize the way medical blood tests are done, both to use a whole lot less blood in doing it.

You know, if anyone's ever been to the doctor and had 5 to 10 tubes of blood removed from them, it can be quite surprising how much they take out.

And it's, you know, that's the limitation of our technology that we need those volumes of blood to run all the tests that we want to.

And so the promise of Theranos was that perhaps with a single drop of blood, we would be able to know as much about the person's, the condition of their body without drawing all that blood.

And thereby, you know, there would be these devices she was gonna create that would sort of do it, you put a drop of blood in it, and it spits out everything you ever wanted to know about what's in your bloodstream.

And in a way, that would make it so much easier.

You know, it could be, you could have 1 in your home, theoretically, and you, I don't know why you'd wonder what your potassium level is on any given day, but you could check if you wanted to.

You know, I put that goal up there with the frontier of making painkillers that are as good as opioids without the addictive quality.

You know, that would be such a huge revolution if we did have that in medicine.

But particularly for me, because I trained in both pediatrics and internal medicine, so I learned to care for both children and adults, in children we do draw much less blood.

And we use these tiny little tubes to draw their blood, and we seemingly get equivalent information out of the larger tubes we draw from adults.

And I'm still unclear, to be honest, why we can't draw that little amount of blood from adults.

I'm sure there are, or else we'd be doing it.

But I do think that that is a very important goal.

And if Theranos had done it, they would have really revolutionized the practice of medicine.

So to return to that cadaver, that first day, when you got to meet with a dead, with a human body that's no longer living.

So how quickly did it take for you to get used to sort of, you said, looking at the surface muscles of the back?

I mean, that can be overwhelming as a thought, and people listening to this that have never dissected anything might be overwhelmed by that thought.

So like, how quickly were you able to get used to the brutal honesty of the biology before you?

I guess I've never been a squeamish person, so for me, it was kind of riveting and fascinating right from the first moment.

But I do know some of my fellow classmates did have some trouble with it.

Some of them I heard had nightmares in the first few weeks of anatomy lab.

But then everyone, as far as I know, got used to it.

And that was also actually a big lesson for me, that it's pretty amazing what people can get used to in their daily lives.

And I kind of extrapolated that to people living through war and through just terrible situations and living under oppressive regimes.

And it really is amazing what people can get used to, almost anything.

But you know, in war, people often come back and they have nightmares, they suffer through it, there's PTSD, there's a lot of complicated feelings with that.

Are echoes of those same complicated feelings possible in the case of training to be and becoming a doctor?

Yeah, I think sometimes just as a barbed wire fence can leave a scar on your skin, emotional, psychological experiences can leave a mark on your brain or your memory.

And I think that that definitely could be a problem in medical training.

You do see a lot of things that are very shocking, very repulsive, things that you'd never forget.

I know 1 of those students that had nightmares initially went on to be a surgeon.

So I imagine she's not having the PTSD of kind of seeing inside her first dead body because she sees inside them all day every day now.

You know, we go on to see so many kind of grosser or more shocking things in medical training through medical school and then by working with actual living patients, not just dead and embalmed bodies.

So I do think that things can leave a mark, but I don't think that initial cadaver would be the most traumatic.

Yeah, but maybe some of that trauma, the demons make you a better surgeon, just like some of your own psychological trauma might make you a better psychiatrist.

is it order or is it chaos to the ordering of the chapters from throat and heart and feces and genitals all

So I did mention that throat was the first 1 because I kind of wanted to throw the reader right into the brutal honesty of death.

And I followed it up with feces as the third chapter in a way partly to also throw them right into the deep end of how I like discussing parts of the body and revealing their gross and fascinating aspects.

You know, when you train to be a doctor, everything is on the table, literally, in the cadaver lab, but also just, you know, you deal with blood and piss and vomit and feces and that's kind of the medium of your craft and...

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Jonathan Reisman: The Human Body - From Sex & Sperm to Hands & Heart | Lex Fridman Podcast #297