Do We Have to Die? with Venki Ramakrishnan

Why do we die? Do we have to? Neil deGrasse Tyson, Chuck Nice, and Gary O’Reilly explore the paradox of death, the science of aging, and the search for immortality with Nobel Prize-winning structural biologist Venki Ramakrishnan.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Neil deGrasse Tyson?

  Why are you bombing us out with a topic on why we die?

• 0:02Gary O'Reilly?

  Because we have a Nobel Prize winner as our guest.

• 0:05Neil deGrasse Tyson?

  Dude, we have a comedian, it's a happy show.

• 0:07Chuck Nice?

  It is a happy show because we're not talking about me dying on stage for once.

• 0:13Neil deGrasse Tyson?

  Coming up on StarTalk, how and why we die.

• 0:19Neil deGrasse Tyson?

  Welcome to StarTalk, your place in the universe where science and pop culture collide.

• 0:28Neil deGrasse Tyson?

  StarTalk begins right now.

• 0:32Neil deGrasse Tyson?

  This is StarTalk. Neil deGrasse Tyson, your personal astrophysicist, this is special edition, which means we've got Gary O'Reilly. Gary?

• 0:41Gary O'Reilly?

  I'm Neil.

• 0:42Chuck Nice?

  Hey. And we got Chuck Nice.

• 0:44Neil deGrasse Tyson?

  Hey, hey. Okay. What's happening? And special edition specializes in all science that matters to the human condition.

• 0:52Gary O'Reilly?

  Yes.

• 0:52Neil deGrasse Tyson?

  And today's topic is no exception.

• 0:56Gary O'Reilly?

  No.

• 0:56Neil deGrasse Tyson?

  And I, may I give the title of it?

• 1:00Gary O'Reilly?

  Please do.

• 1:00Neil deGrasse Tyson?

  Why we die. Dun dun dun.

• 1:06Neil deGrasse Tyson?

  Why we die. Well, I have no expertise in that other than simply being alive. Right.

• 1:14Neil deGrasse Tyson?

  But I fear death because I'm born knowing only life. Wow, look at that. Yeah. I got that from a movie. Oh, okay.

• 1:22Gary O'Reilly?

  That's okay. So, Lane and I are co-producer on this.

• 1:26Neil deGrasse Tyson?

  Lane Unsworth, our LA producer for StarTalk, yes.

• 1:29Gary O'Reilly?

  We have long wanted to investigate this subject matter.

• 1:33Chuck Nice?

  You want to investigate it, but not firsthand?

• 1:35Gary O'Reilly?

  No.

• 1:38Gary O'Reilly?

  More an observation, more an observation. So if you put it this way, humankind has for millennia asked, why do we die? Followed by, well, why can't we live forever then? And then?

• 1:50Neil deGrasse Tyson?

  It's kind of the same question.

• 1:51Gary O'Reilly?

  Yeah, but, you know, different people. So has evolution programmed us to expire on a certain date? Could we extend the game? Cheat death, play god, if you wish. Millions, if not billions, are spent annually on anti-aging, be it research or products.

• 2:07Neil deGrasse Tyson?

  Millions of dollars.

• 2:09Gary O'Reilly?

  Yes. And so how close are we to unlocking? The mystery of death. So no surprise that the research into proteins is proving to be the key to this mystery.

• 2:22Neil deGrasse Tyson?

  So the building blocks of life may hold the key to death?

• 2:25Gary O'Reilly?

  How about that?

• 2:26Neil deGrasse Tyson?

  Oh, good sentence there. Very good, Chuck. So we have the world's expert on this very subject. Wow. And this is Venky Ramakrishnan. Venky, welcome to Stark Talk.

• 2:37Speaker 03

  Thank you.

• 2:37Neil deGrasse Tyson?

  Excellent. And you are now based in Cambridge?

• 2:41Speaker 03

  Yes, England. Say it.

• 2:44Neil deGrasse Tyson?

  I knew, I knew you had to fix that.

• 2:47Speaker 03

  Wasn't really necessary. It's always basher Brit day here.

• 2:52Neil deGrasse Tyson?

  Yeah, yeah, it is, it is. But we do it lovably.

• 2:55Speaker 03

  We do, yeah.

• 2:56Neil deGrasse Tyson?

  So you run a small group, but it used to be bigger because you're winding down in your career. A program leader at the M R C?

• 3:06Speaker 03

  That stands for Medical Research Council.

• 3:08Neil deGrasse Tyson?

  Lab at Cambridge? Yes, and it specializes in bio?

• 3:13Speaker 03

  Molecular biology.

• 3:14Neil deGrasse Tyson?

  Molecular biology.

• 3:15Speaker 03

  So it's the M R C lab of molecular biology.

• 3:17Neil deGrasse Tyson?

  Okay, okay. Our name is what we do. But that's like the least of your resume here. So in 2009, you were awarded the Chemistry Nobel Prize. Wow. Why? Are you wearing it under your shirt right now?

• 3:34Speaker 03

  No.

• 3:36Neil deGrasse Tyson?

  Because that's serious bling, you know? Honestly. You go to the club. Yeah, I would be like the Flavor Flav of Nobel Prize winners. I would never take it off. So a former president of the Royal Society, very important. That's a deal. Organization that basically the first, we think the first in the world to organize the ideas and publications of scientists. Wow. To make it a clearinghouse of peer review.

• 3:59Speaker 03

  First peer reviewed papers. Also advocated evidence-based science in the 17th century at a time when authority mattered a lot. And they said, authority doesn't matter. Beauty doesn't matter. It's evidence that matters.

• 4:14Neil deGrasse Tyson?

  Very enlightened and important posture. And then you got knighted in 2012. That's three years later. And you, do they knight with an actual sword?

• 4:27Speaker 03

  Yes, but it's, I think it's blunt.

• 4:30Neil deGrasse Tyson?

  Well, let's just hope. You don't want for the slip up. Right. If there's a little sort of jiggle in the wrist. We wanted to make him a knight, it turned into an execution.

• 4:43Gary O'Reilly?

  Who was on the other end of the sword?

• 4:45Neil deGrasse Tyson?

  Yes.

• 4:46Speaker 03

  Uh, it was Princess Anne.

• 4:49Gary O'Reilly?

  Oh, cool.

• 4:49Neil deGrasse Tyson?

  Cool. We like it. We love Princess Anne. Yeah.

• 4:52Gary O'Reilly?

  That'll work.

• 4:52Neil deGrasse Tyson?

  Yeah, yeah. Also, you have a book. Um, it's your second book. First one a few years back, The Gene Machine. But what we're especially interested in now is Why We Die. And give me the subtitle of that book, Why We Die.

• 5:06Speaker 03

  It's called The New Science of Aging and the Quest for Immortality.

• 5:11Neil deGrasse Tyson?

  Well, let's dive right in because you are our world's expert in this. And before we can define death, I guess we should kind of define life and then learn what it is that ceases in life that then brings death upon it.

• 5:27Speaker 03

  Well, defining life is very hard. It's, you know, you could almost say, quote, Justice Potter Stewart, as, "I can't define it, but I know what I see."

• 5:38Neil deGrasse Tyson?

  Spoken, maybe you don't know. Pornography. Because that's America. He said that of pornography.

• 5:43Speaker 03

  But the fact is, um, life, most biologists would define it as a system that can self-replicate and evolve. And at least in our world, it's carbon-based. But when we talk about death, it's a little complicated because there are many different kinds of death.

• 6:04Neil deGrasse Tyson?

  Oh.

• 6:05Speaker 03

  You can have societies dying, cities dying, nations dying. Um, you can have companies dying. But what we're talking about is the death of the individual, which has a-

• 6:18Neil deGrasse Tyson?

  The organism.

• 6:19Speaker 03

  Of an individual animal or organism.

• 6:23Speaker 03

  And there's a peculiar paradox there because while you're alive, I mean, right now, millions of cells in your dying, you don't even notice that, okay? That's cell death.

• 6:34Neil deGrasse Tyson?

  Why you gotta tell me that right now?

• 6:36Speaker 03

  No, they need to die in order to, in order to keep you alive.

• 6:42Chuck Nice?

  Oh, look at that.

• 6:43Neil deGrasse Tyson?

  That's how he got out of that.

• 6:44Chuck Nice?

  Thank you, dead cells.

• 6:46Speaker 03

  So.

• 6:46Neil deGrasse Tyson?

  To make room for the new cells.

• 6:48Speaker 03

  To make new room for new cells, actually during development, cells will die at precise points as during development. They've done their bit and then they have to get out of the way.

• 6:57Neil deGrasse Tyson?

  When you say development, mean embryonic?

• 6:59Speaker 03

  Embryonic development, correct. At the same time, when you die, when you say a person has died, at the point of death, most of you is still alive. That's why you can donate organs.

• 7:10Chuck Nice?

  Right.

• 7:10Speaker 03

  Okay?

• 7:11Gary O'Reilly?

  So there's the other side of the paradox.

• 7:13Neil deGrasse Tyson?

  Interesting.

• 7:14Speaker 03

  So, what do we mean by death? Okay? You're gonna have, by the way, since you're an astrophysicist, you're gonna have death of the universe as well, and there's a book coming out on that, or has come out. So, the question is, what do we mean when an individual dies? What we mean is the irreversible loss of that individual's ability to function as a coherent whole. So that means that person can no longer exist as a, as a unit. And that's what we mean by death.

• 7:44Chuck Nice?

  And are you talking physiologically, this person cannot function as a unit? Because there are people who experience brain death, or to an extent, and they keep them on a respirator because a family member says, "I don't want them to die."

• 8:01Neil deGrasse Tyson?

  So there are two examples coming out of Chuck's point. You can be brain dead, but sustained on a respirator, so all your organs are working. And, or, you can be body dead, I suppose, and in the limit, it's like your brain in a jar. Whatever.

• 8:17Gary O'Reilly?

  It can't, it can't happen. But that's more like a pontio presi.

• 8:20Speaker 03

  That can't, what you said can't happen, because if your body's dead, then it can't feed nutrients to the brain to keep it alive. The brain is the biggest consumer of.

• 8:29Neil deGrasse Tyson?

  Resources.

• 8:30Speaker 03

  Resources. So, coming back to your point, though, about brain death, that's interesting, because... It used to be that if your heart stopped beating, that was the moment people said you're dead.

• 8:42Chuck Nice?

  Right, right.

• 8:42Speaker 03

  Then they found out that actually, even if your heart stops beating, they can resuscitate you.

• 8:46Chuck Nice?

  Right.

• 8:47Speaker 03

  But then they decided, okay, when you no longer have brainwaves and your brain has irreversibly stopped, that's brain death. And that's an interesting case. States in the US used to have different definitions of death. And there was a case where somebody died in California, but her relatives wouldn't accept it. And by New Jersey laws, she was not dead. So they moved the body to New Jersey.

• 9:13Chuck Nice?

  Oh, wow.

• 9:13Speaker 03

  And she was maintained, as you say, on some sort of artificial device. And then eventually, she died. But this is slightly getting semantic because most people agree that there's a point when the body cannot reverse itself and get back to being alive.

• 9:33Neil deGrasse Tyson?

  Yeah, but that's a statement of the limits of medicine in the day.

• 9:36Speaker 03

  Today.

• 9:36Neil deGrasse Tyson?

  Right. So I remember, I mean, I read this, that one of the definitions of death is if you do not fog a mirror held up to your mouth.

• 9:45Speaker 03

  Yeah.

• 9:46Neil deGrasse Tyson?

  And I'm thinking-

• 9:47Speaker 03

  That's respiratory.

• 9:48Chuck Nice?

  Yeah, that was a long time.

• 9:49Neil deGrasse Tyson?

  I'm thinking, you know, I'm glad that's not when I'm alive. I mean, I'm just thinking, thank you for-

• 9:55Chuck Nice?

  Right, thanks for not being alive back then. Because I'm a light sleeper.

• 9:59Neil deGrasse Tyson?

  Okay, so that tells me that however real our current definitions feel about when someone dies could be modified in the near or distant future.

• 10:09Speaker 03

  Absolutely. And neither birth nor death are very clearly defined. And I've pointed this out, that they're both somewhat fuzzy. I mean, when is it that you actually are you at birth? And that's the whole argument about abortion and all of that is just about that. And similarly, the point of death is also a little fuzzy.

• 10:34Chuck Nice?

  When you're no longer you.

• 10:34Speaker 03

  Yeah.

• 10:34Chuck Nice?

  Yeah, that's wild, yeah.

• 10:37Gary O'Reilly?

  So the bit in between is aging.

• 10:38Speaker 03

  The bit in between is aging. And unfortunately for us-

• 10:41Neil deGrasse Tyson?

  The little bit in between. Your whole life.

• 10:44Gary O'Reilly?

  I may have downplayed that.

• 10:45Neil deGrasse Tyson?

  Okay.

• 10:45Speaker 03

  And in fact, you start aging even in utero.

• 10:49Gary O'Reilly?

  Interesting.

• 10:49Speaker 03

  From the time you're conceived, you know, your fertilized egg starts to develop.

• 10:54Chuck Nice?

  Is that why all children are born looking like old men?

• 10:58Neil deGrasse Tyson?

  Winston Churchill. So that's even earlier than a loaf of bread. Cause you know when a loaf of bread starts aging? No. Right when you take it out of the oven. Exactly. Okay. In that moment, it starts getting old. Right. Right, but here.

• 11:12Speaker 03

  This is in the oven.

• 11:13Neil deGrasse Tyson?

  In the oven, you're getting old. Look at that.

• 11:25Speaker 04

  Hey, this is Kevin the Sommelier and I support StarTalk on Patreon. You're listening to StarTalk with Neil deGrasse Tyson.

• 11:39Neil deGrasse Tyson?

  Forgive me as an astrophysicist, I hear talk of cells and, and, but then I also hear talk of proteins. So could you distinguish the two of them for me with regard to the role of aging?

• 11:51Speaker 03

  So aging is, you can think of aging as an accumulation of damage and changes to our molecules, our cells, our tissue and entire organs and the body. And this aging occurs at every one of those levels. So if you think of the molecule that holds all the information necessary to make all of the other molecules in the cell, that's our genes, our DNA. So DNA can be damaged. It can also change, which is not exactly damaged, but it can be modified as we age, typically by adding chemical groups to it, often methyl groups.

• 12:33Neil deGrasse Tyson?

  It's gene editing.

• 12:35Speaker 03

  It's, uh, it's epigenetics. It's not editing as such. It's not changing the bases. It's not changing the letters of the DNA.

• 12:44Neil deGrasse Tyson?

  That would be gene editing.

• 12:45Speaker 03

  That would be gene editing.

• 12:46Neil deGrasse Tyson?

  Okay.

• 12:47Speaker 03

  This is epigenetics, which means sort of on top of, of genetics.

• 12:52Neil deGrasse Tyson?

  Like the epicenter of an earthquake is the point on our surface above where the.

• 12:57Speaker 03

  Right.

• 12:57Neil deGrasse Tyson?

  Yeah.

• 12:57Speaker 03

  And so you can, you can modify DNA and that changes. The way in which the program is expressed. So which genes are translated into protein.

• 13:10Neil deGrasse Tyson?

  So this is the playing god part because now you are changing the.

• 13:15Speaker 03

  No, we're not doing anything. This is happening. This is happening even in utero.

• 13:20Chuck Nice?

  Experiential circumstances can change your epigenetics. Is this the translation control of proteins?

• 13:26Speaker 03

  It's just part of life and it evolved for probably a very good reason. Mainly, it may have been of a cancer prevention mechanism early in life. We can get into why we have death from an evolutionary point of view. But nevertheless, the DNA program itself ages. You know, damage and modifications change the nature of the genes that you're expressing. Then that results in the proteins which are encoded by DNA.

• 13:58Neil deGrasse Tyson?

  There you go.

• 13:59Speaker 03

  These are the workhorses of the cell. They carry out all the function. They give out, they give the cell its structure. Almost everything you think of as a property of life, like vision or touch or, you know, or antibodies, they're all proteins and they're all encoded by DNA. But as we get older, the quality of the proteins deteriorates. They're not made at the right time and the right amount. They start aggregating. You know, Alzheimer's is a case where proteins clump up together and form tangles.

• 14:32Neil deGrasse Tyson?

  In the brain.

• 14:32Speaker 03

  So that also, yeah, in the brain. So that also is a consequence of age. And as a result, things in the cell, larger entities like compartments in the cell, also start to age. One of them are mitochondria, which are, mitochondria were actually bacteria that were swallowed up by a larger cell two billion years ago and then lived in symbiosis. And now, today, mitochondria are specialized as the centers for energy metabolism. It's where oxygen is used to burn sugar effectively and get energy out of it.

• 15:12Neil deGrasse Tyson?

  So it's that kind of chemistry going that far back that accounts for our genetic similarity to life forms that are nothing like us? Like the, you know, we're something like 25% identical genes to a banana?

• 15:26Speaker 03

  Yes, yes. All eukaryotes came out of that.

• 15:29Neil deGrasse Tyson?

  Yes.

• 15:30Speaker 03

  Out of that symbiosis.

• 15:31Neil deGrasse Tyson?

  Okay.

• 15:32Speaker 03

  And so, so you can think of this as an ancient, you know, organelle that's now specialized. And because it's a center for oxygen usage, it can create what are called free radicals or reactive oxygen species, because these are partially reduced oxygen atoms which are chemically very reactive. So there's, you can have a lot of damage.

• 15:58Neil deGrasse Tyson?

  To be clear, if it's fully reduced, that means all the oxygen is where

• 16:01Speaker 03

  It becomes water.

• 16:02Neil deGrasse Tyson?

  And then you can't, there's nothing else that can

• 16:04Speaker 03

  Carbon dioxide and water is what you get.

• 16:06Neil deGrasse Tyson?

  Yes, it's fully reduced. Partially, it's, it's, it's basically activated.

• 16:11Speaker 03

  It's activated, correct.

• 16:12Neil deGrasse Tyson?

  To do things.

• 16:13Chuck Nice?

  And it does damage.

• 16:14Speaker 03

  Yeah.

• 16:14Chuck Nice?

  Yeah.

• 16:15Speaker 03

  And so it can cause damage. And mitochondria have preserved a little bit of their own genome. They used to have a much larger genome when they were bacteria, but now that genome is shrunk. In, in humans, they only encode 13 protein genes, but they're essential for the function of mitochondria. And the mechanism to replicate that DNA, to copy that DNA as mitochondria divide, it's not as accurate as, as the mechanism for our own DNA replication. The more errors creep in. And so mitochondrial aging is a big problem with our aging.

• 16:53Gary O'Reilly?

  Is that a single point of failure in terms of

• 16:55Speaker 03

  It's not a single point. I think aging

• 16:58Neil deGrasse Tyson?

  He's blaming it on the mitochondria.

• 16:59Speaker 03

  Yeah.

• 17:01Gary O'Reilly?

  Some of them might argue.

• 17:03Chuck Nice?

  Aging is like a cascade failure.

• 17:06Speaker 03

  But I do like to say that the reason my grandson has a lot more energy than I do is because he has much better mitochondria.

• 17:14Chuck Nice?

  Right. Something's going on with the mitochondria for your skin, because your skin's perfect. I don't know how old you are, but, you know, clearly I look at your hair and I'm like, okay, this guy's old. But, but I look at your skin, I'm like, but he stole his skin off of a teenager.

• 17:29Neil deGrasse Tyson?

  I thought, black don't crack.

• 17:31Chuck Nice?

  That's true, black don't crack.

• 17:32Neil deGrasse Tyson?

  And that includes

• 17:33Speaker 03

  I think you're absolutely right.

• 17:35Neil deGrasse Tyson?

  The subcontinent.

• 17:36Chuck Nice?

  Yeah, it doesn't make a difference.

• 17:37Speaker 03

  It's the dark skin.

• 17:37Chuck Nice?

  It's the dark skin.

• 17:38Neil deGrasse Tyson?

  Yeah, it's just melanin.

• 17:39Chuck Nice?

  Yeah, that's just melanin.

• 17:40Neil deGrasse Tyson?

  At the end of the day. So this reduced chemistry that makes it Chemically active that could not have been useful before Earth's atmosphere became oxygen-rich.

• 17:53Speaker 03

  That's right.

• 17:53Neil deGrasse Tyson?

  So we had, so that-

• 17:55Speaker 03

  And that happened because of the cyanobacter-

• 17:57Neil deGrasse Tyson?

  Yeah.

• 18:00Neil deGrasse Tyson?

  So cyanobacteria basically turned a carbon dioxide atmosphere into one that had a presence of oxygen. And then anything that needs oxygen can-

• 18:09Speaker 03

  Can thrive.

• 18:10Neil deGrasse Tyson?

  Can now thrive, but it couldn't before then.

• 18:12Speaker 03

  That's good.

• 18:12Neil deGrasse Tyson?

  So that helps age date, or time date, I should say.

• 18:16Speaker 03

  It's about 2 billion years.

• 18:17Neil deGrasse Tyson?

  That helps time date these activities, yeah. Interesting.

• 18:20Gary O'Reilly?

  That's the watershed moment for-

• 18:21Neil deGrasse Tyson?

  Ooh, very, very good.

• 18:23Speaker 03

  Yeah, look at you.

• 18:24Neil deGrasse Tyson?

  Watershed.

• 18:24Speaker 03

  I like that, that was good.

• 18:26Gary O'Reilly?

  So there's something called senescent cells, where they age and they secrete these sort of inflammatory-

• 18:31Speaker 03

  Yeah, so senescent cells are another, I mean, I said you can have aging at every level. And aging at this, at a cellular level is often due to senescence. And senescence is interesting. It may have evolved originally as a anti-cancer mechanism, or as a mechanism to get rid of defective cells.

• 18:52Gary O'Reilly?

  Yeah.

• 18:53Speaker 03

  So what happens is, if a cell gets DNA damage, it has a number of enzymes to repair the damage, to sense and repair the damage. But if the damage is too extensive, then it triggers pathways to either kill the cell-

• 19:10Neil deGrasse Tyson?

  Right.

• 19:10Speaker 03

  Commit suicide, or to send it into the state called senescence.

• 19:14Gary O'Reilly?

  Yeah.

• 19:15Speaker 03

  That can also happen, you know, due to other kinds of stresses. And what senescent cells do is they no longer function normally, and they no longer divide, but they secrete inflammatory compounds. And the purpose is to signal to the immune system that there's something wrong here, and come and repair the damage around this site, maybe it's a wound, or infection, or something.

• 19:38Gary O'Reilly?

  They call the cavalry.

• 19:39Speaker 03

  And, exactly, call the cavalry.

• 19:41Neil deGrasse Tyson?

  So it has utility-

• 19:42Speaker 03

  It has, it has utility early in life.

• 19:44Neil deGrasse Tyson?

  Early, until it doesn't.

• 19:46Speaker 03

  But later in life, you get too many of these events.

• 19:49Neil deGrasse Tyson?

  Right.

• 19:49Speaker 03

  Build up of senescent cells, systemic inflammation, which causes organ damage, more senescence. And so it's a big problem in aging.

• 19:59Chuck Nice?

  Wow. Yeah, and that's why you see so many medical reports now that talk about the dangers of inflammation.

• 20:07Speaker 03

  Absolutely.

• 20:08Chuck Nice?

  Totally. Like, it doesn't make a difference what kind of inflammation. The idea is to eliminate inflammation as much as you can, no matter what.

• 20:15Speaker 03

  Sure. And actually, people know, for example, in the COVID pandemic, the cause of death is often triggered by inflammation.

• 20:25Chuck Nice?

  Right.

• 20:25Speaker 03

  Not by necessarily directly by the virus.

• 20:29Chuck Nice?

  By the virus itself. It's a reaction. So it's the cytokine storm that was created as a reaction to the virus itself. Cytokine? Cytokine. Please explain. Cytokines are, if I'm not mistaken. Or we can get him to answer. Oh, can you answer that?

• 20:44Chuck Nice?

  Yeah, because I'm not an expert.

• 20:45Speaker 03

  I'm not an immunologist.

• 20:50Chuck Nice?

  But yeah, the cytokines was released when we respond to what our body thinks is an attack on us. And. Sometimes it goes into overdrive. And goes into overdrive, yeah.

• 21:02Gary O'Reilly?

  Are we anywhere close to being, or is this the epigenetics thing where we can deal with these senescent cells?

• 21:08Speaker 03

  No, but there is a new field emerging, which is cellular reprogramming.

• 21:14Chuck Nice?

  Ooh, yeah, that sounds sexy.

• 21:17Speaker 03

  To explain that, if you start from a single fertilized egg, it divides into many cells, becomes something called a blastula, and then, or a blastocyst, and then you, it divides further and further, and then forms specialized stem cells, and each of those specialized stem cells give rise to certain kinds of tissues.

• 21:41Chuck Nice?

  Yes, right.

• 21:42Speaker 03

  Okay, so some stem cells will only generate cells of the blood system, including white blood cells, red blood cells, and so on. That used to be thought of as unidirectional. You go, you can't go backwards. You can't go back from a skin cell, back to a fertilized egg or an early embryo. But that turned out not to be true. Okay, and I actually, it was done in a natural way when Dolly the Sheep was cloned, but actually even earlier, when John Girdon cloned the skin cell of a frog and cloned an entirely new animal from it.

• 22:21Chuck Nice?

  Wow.

• 22:22Speaker 03

  And, and that meant that somehow these marks on the DNA had been erased and/or changed.

• 22:30Neil deGrasse Tyson?

  Just historically, that completely changed the public dialogue about our source of stem cells.

• 22:39Chuck Nice?

  Right.

• 22:39Neil deGrasse Tyson?

  Because we, we only were getting them from aborted fetuses.

• 22:43Chuck Nice?

  Blood, yeah.

• 22:44Speaker 03

  From fetuses.

• 22:44Neil deGrasse Tyson?

  From fetuses. And so that was a complicated ethical issue for many people.

• 22:50Chuck Nice?

  Right.

• 22:50Neil deGrasse Tyson?

  And then, once this, that blew open that whole field.

• 22:53Speaker 03

  Right, well, that wasn't Girdon and Dolly the Sheep and others, but it was actually Shinya Yamanaka, a Japanese scientist, who showed that if you were to introduce just four factors, these are genes for proteins that regulate other genes.

• 23:12Chuck Nice?

  Got you.

• 23:13Speaker 03

  If you were able to introduce those four factors, you could take a fully differentiated cell, like a skin cell or a liver cell or a heart cell, and you could make it go backwards in development, all the way back to what's called a pluripotent stem cell. Pluripotent means it can make any tissue.

• 23:31Chuck Nice?

  Right.

• 23:31Speaker 03

  And so, that eliminated the need for what you said, which is getting...

• 23:36Gary O'Reilly?

  Did he not win a Nobel for that as well?

• 23:37Chuck Nice?

  He better had.

• 23:38Speaker 03

  He and John Girdon shared a Nobel Prize. And here's an interesting thing. John Girdon's paper for which he won the Nobel Prize was published the year Shinya Yamanaka was born.

• 23:49Chuck Nice?

  No. Wow.

• 23:51Speaker 03

  That's how far apart they are in age.

• 23:53Chuck Nice?

  And all that time, all that work, and then he just comes along and takes credit for it. Look at that, would you, look at that.

• 23:59Gary O'Reilly?

  We've had, we've had sort of variations of this with David Sinclair, who we've had a guest as a guest, took mice that were blind.

• 24:07Chuck Nice?

  Correct.

• 24:07Gary O'Reilly?

  It sounds like a nursery rhyme.

• 24:09Neil deGrasse Tyson?

  Three of them.

• 24:09Gary O'Reilly?

  Back start.

• 24:13Gary O'Reilly?

  You did it, didn't you?

• 24:13Neil deGrasse Tyson?

  Yeah, yeah. Somebody had to go there.

• 24:15Gary O'Reilly?

  You did.

• 24:16Neil deGrasse Tyson?

  Go, go.

• 24:17Gary O'Reilly?

  And turned them into sight, cured their blindness.

• 24:21Speaker 03

  Yeah.

• 24:21Gary O'Reilly?

  So, I mean, if that's the case, how far are we from?

• 24:25Speaker 03

  I would say it's early days. Yeah. Okay.

• 24:29Gary O'Reilly?

  I can tell you that I'm aware that this has happened, and then my question is, just the distance between this and doing other things on a grander scale. Mine's the one thing, larger primates.

• 24:39Speaker 03

  Yeah, and curing blindness, it's a little further down the line, is what you're saying. It's a little... But, the idea is, we do have, would you say we now have a, not a blueprint, but maybe a template, that we know we can take these programming cells and use them to maybe change our makeup? I think the biggest use of that is in something called regenerative medicine, where if you want to replace tissue that normally can't be replaced, for example, damaged heart muscle in a heart attack, or pancreatic tissue which has been destroyed

• 25:24Speaker 03

  and you have diabetes, or cartilage, for example, for osteoarthritis. Absolutely. And maybe one day, I'm hoping, even hair.

• 25:35Speaker 03

  So, if you can... It looks good on you, though. Very few people can pull this off, okay? Anyway, so if you can do that, regenerative medicine is a huge area of research. Yeah. And they're making good progress in some things.

• 25:50Neil deGrasse Tyson?

  Just to be clear, I've always been disappointed in humans for not being able to regenerate limbs the way newts do.

• 25:56Speaker 03

  Exactly. That's because newts have stem cells all over... All over their body? All over their body. Their whole makeup. Yeah, it's spread out throughout, and so they can...

• 26:06Neil deGrasse Tyson?

  I'm just saying, we're old enough to remember reading biology books, "Humans are the top of the evolution," back when we spoke that way.

• 26:13Speaker 03

  Unless you lose an arm.

• 26:18Neil deGrasse Tyson?

  I went through the list of all the other animals that do things way better than we do, and I quickly read...

• 26:24Gary O'Reilly?

  It's not a short list.

• 26:26Speaker 03

  It's humbling to know that we have about the same number of genes as a worm or a weed. Right, yeah, there you go.

• 26:33Gary O'Reilly?

  You put us in our place.

• 26:34Neil deGrasse Tyson?

  Yeah.

• 26:35Speaker 03

  Anyway, but going back to stem cells, the thing with aging is, can you...

• 26:41Speaker 03

  Take a fully grown or an aged individual, apply these kinds of factors, and get their tissues or their stem cells to be regenerated. Right. Because one problem with aging is that our stem cells also age. Right. They decline in number and in quality. So if you were able to take, use a method that would somehow either rejuvenate tissue or actually regenerate stem cells, that would be a big thing. And people have done experiments to do this kind of thing in mice. And they say that the mice, I mean, the papers report that the mice look healthier, they seem younger by many criteria and so on. But how to do this safely?

• 27:25Speaker 03

  And the bald mice, did they get hair back? No, but their fur looked better. Oh, okay, okay. That's not bad. So, so the question is, how can you do this in humans in a way that's safe, that doesn't cause cancer, that is at the right dose and so on? Right. And that's a big challenge. It is. So I, I think it's promising, but like many of these things, you know, the aging field, I should say, is full of hype. Okay? Yeah. And it's very promising, but there's a lot of work to be done before it's ready for prime time. Mm-hmm.

• 28:00Gary O'Reilly?

  Are we at this sort of Frankenstein moment? I mean, you've done a Frankenstein show before with the, let me get his name right, David Andrussevich.

• 28:07Speaker 03

  Yes.

• 28:08Gary O'Reilly?

  Mm-hmm, mm-hmm. You know, the cells were, we've said there can be death to the organism, but cells will remain alive. And now we've got the Yamanaka factors. Are we getting to that thing when we can create? Or are we just fantasy talking here?

• 28:24Speaker 03

  You mean, create a new individual?

• 28:26Gary O'Reilly?

  Hmm.

• 28:27Speaker 03

  Or the same individual?

• 28:28Gary O'Reilly?

  Well, the same individual.

• 28:29Speaker 03

  You could certainly clone yourself. Right. That's theoretically and practically possible. They've cloned all kinds of mammals. There's no reason why they can't clone a human being. Except that all countries have decided that's a bad thing to do. But that's not the same as rejuvenating the same individual.

• 28:49Chuck Nice?

  Right, right. Which, by the way, for selfish purposes rejuvenation is a hell of a lot better than cloning. Because that clone is not me.

• 28:59Speaker 03

  Exactly. People forget that.

• 29:02Neil deGrasse Tyson?

  Yeah, and there's all this fantasies of in the multiverse where you have an infinite number of possible molecular outcomes of all organisms, they're imagining themselves in another universe in a way being reincarnated and living forever. It's like, no, that's a different person.

• 29:19Chuck Nice?

  That's just a different person in a different timeline.

• 29:20Speaker 03

  And by the way, these transhumanists, you know, people who think that they're going to dump their brain into a computer and then maintain their consciousness. A simple question to ask is, what if you make two copies of it? Which one's the real you? And you immediately have a paradox.

• 29:36Chuck Nice?

  Absolutely.

• 29:37Gary O'Reilly?

  The copies that you make will be of you of that moment, but you've in the timeline are still proceeding. They would be stuck.

• 29:43Neil deGrasse Tyson?

  You still get to go to the beach and have friends and your your brain in a jar does not, right?

• 29:48Chuck Nice?

  Oh, gosh.

• 29:49Neil deGrasse Tyson?

  Or your brain in the silicon chip.

• 29:50Gary O'Reilly?

  It's you from whenever it was you created it.

• 29:53Neil deGrasse Tyson?

  So, so I heard long ago, and I checked it out, and I think it's true, that all mammals live for about the same number of heartbeats, except for humans who live two or three times that. Except if you go back far enough in time when we were just living in caves, we were right with all the rest of the mammals. So first, is that true? Second, there are animals, not mammals, that live much longer than we do. I'm thinking of the Galapagos tortoise, for example. So do you guys study other animals to get insight?

• 30:25Speaker 03

  So there is a whole field devoted to looking at lifespan of different species. And you are right that, at least among mammals, Jeffrey West, who's written a book called "Scale," shows that the number of heartbeats is roughly the same. That has to do with the fact that smaller animals have a higher metabolic rate. They have a faster metabolism. And they almost need to because their surface-to-volume ratio is larger, they dissipate heat more.

• 30:54Neil deGrasse Tyson?

  We did a whole explainer on surface-to-volume ratios.

• 30:57Speaker 03

  And so they need to maintain a higher metabolic rate. That's one of the reasons.

• 31:04Neil deGrasse Tyson?

  Well, that's only one of the reasons why they have higher heart rate. That's not a reason why they should die sooner.

• 31:10Speaker 03

  Ah, the why we should die sooner is, has an evolutionary explanation. And that is, evolution doesn't care how long you live. It only cares about fitness. Fitness, in the biological sense, is the likelihood that you're going to be able to successfully pass on your genes.

• 31:30Neil deGrasse Tyson?

  And people always misinterpret that as being physically fit, or stronger, or whatever. Survival of the fittest. I'm in great shape. Yeah, Darwin should have found a different word for that.

• 31:41Speaker 03

  So, evolution cares about fitness. Now, at the same time, for most of our history, and certainly the history of all other species, resources are limiting. And so, you have to select, do you put more of your resources into maintenance and repair of the individual animal, or do you put it into growth and reproduction? There's always a balance, if you have limited energy. So, in the case of a mouse, which lives about two years in the wild, there's no sense in having a mouse live for 40 years, because long before that, it's going to be eaten.

• 32:21Neil deGrasse Tyson?

  Eaten, yep.

• 32:22Speaker 03

  Exactly. You beat me there. Or it'll die of starvation, or drought, or something. And so, in the case of a mouse, evolution has favored selection of a species that grows very quickly and reproduces prolifically. That's a mouse. If you get to a large animal, like a bowhead whale...

• 32:44Speaker 03

  Let's take a, an even, even bigger than an elephant. They can live for two, three hundred years and they have a very relatively slow metabolism.

• 32:51Chuck Nice?

  Wow.

• 32:52Speaker 03

  An even slower metabolism is not a mammal, but it's still a vertebrate called the Greenland shark. Seven hundred years.

• 32:59Gary O'Reilly?

  Whoa.

• 33:01Speaker 03

  A vertebrate, living for seven hundred years, very slow metabolism.

• 33:04Neil deGrasse Tyson?

  Wait, wait, wait, wait, wait. How do you know that? We didn't even have marine biology seven hundred years ago.

• 33:09Speaker 03

  They, they can do things like carbon dating.

• 33:14Gary O'Reilly?

  They cut one open and it was all seven hundred rings.

• 33:19Neil deGrasse Tyson?

  Okay, I'm just, I'm just weird.

• 33:21Gary O'Reilly?

  So you've got the mayfly lives a day.

• 33:24Speaker 03

  Mayfly lives a day, exactly.

• 33:25Gary O'Reilly?

  And then between that, you've gone from there to a Greenland shark.

• 33:28Speaker 03

  And your Galapagos. And there are actually other animals that are thought not to even age biologically.

• 33:33Gary O'Reilly?

  What's the immortal jellyfish?

• 33:34Speaker 03

  Like the hydra and the immortal jellyfish. These things have.

• 33:37Neil deGrasse Tyson?

  Wait, there's an actual animal called the hydra?

• 33:39Speaker 03

  Yes.

• 33:40Chuck Nice?

  Awesome.

• 33:40Neil deGrasse Tyson?

  Not just in, in.

• 33:41Chuck Nice?

  Not just in G I Joe?

• 33:42Neil deGrasse Tyson?

  No, no.

• 33:43Chuck Nice?

  Oh, no, Marvel.

• 33:44Neil deGrasse Tyson?

  No, no, no, in, in, in.

• 33:46Speaker 03

  In mythology.

• 33:47Chuck Nice?

  Oh, you mean the real hydra?

• 33:49Neil deGrasse Tyson?

  Yes.

• 33:49Chuck Nice?

  Oh, yeah.

• 33:50Speaker 03

  This is a freshwater, a small animal. And, and they're full of stem cells, so they're constantly regenerating themselves. But if you followed an individual, it would also age only very slowly. It's just in the wild, it, it, it dies for other reasons before actually aging.

• 34:07Chuck Nice?

  Mm-hmm.

• 34:08Speaker 03

  So, so there's a whole range.

• 34:10Neil deGrasse Tyson?

  So humans might be the only species that dies of natural causes in the world. I mean, if you want to think about it that way.

• 34:18Speaker 03

  Possibly, you know.

• 34:19Neil deGrasse Tyson?

  We're apex predator.

• 34:20Speaker 03

  Yeah.

• 34:21Neil deGrasse Tyson?

  So.

• 34:22Speaker 03

  Yeah, I think that may be true. In fact, there, there's a book written by Stephen Ostad called Methuselah Zoo, which, where he talks about all these animals.

• 34:32Chuck Nice?

  He loves that title. Methuselah Zoo.

• 34:34Neil deGrasse Tyson?

  Love it.

• 34:34Speaker 03

  And it's, it's a great book.

• 34:36Neil deGrasse Tyson?

  So that reminds me, because Methuselah's the oldest person in the, in the Bible.

• 34:40Chuck Nice?

  Right.

• 34:41Neil deGrasse Tyson?

  In the, in the.

• 34:42Chuck Nice?

  In the Old Testament.

• 34:43Neil deGrasse Tyson?

  Old Testament Bible. The oldest star we know of in our galaxy is called Methuselah.

• 34:47Chuck Nice?

  It's called Methuselah.

• 34:47Neil deGrasse Tyson?

  Yeah.

• 34:48Chuck Nice?

  Right.

• 34:48Neil deGrasse Tyson?

  So Methuselah had a lot of influence.

• 34:50Chuck Nice?

  Yeah. And that star too is lying about its age.

• 34:56Chuck Nice?

  Who knew that?

• 34:59Speaker 03

  Anyway, in this book, he points out.

• 35:02Neil deGrasse Tyson?

  Methuselah Zoo.

• 35:03Speaker 03

  In Methuselah Zoo, he points out how all these species have such different lifespans. And it's because of this evolutionary selection, but it's actually worse than that. It's, the fact is, evolution will select for things that help you early in life, even if they cause a problem later in life. So many of the things that cause aging are related to growth, for example, or to cancer prevention, you know, prevention of, or senescent cell creation. These things all help us early in life, and they're a problem later in life. But evolution doesn't care what happens to you when late in life.

• 35:42Neil deGrasse Tyson?

  When you're not making babies.

• 35:43Speaker 03

  Right, exactly.

• 35:43Chuck Nice?

  Yeah, because that's the whole deal.

• 35:45Gary O'Reilly?

  So what helps us survive in infancy and then go on to reproduction is the key component of our decline and demise?

• 35:52Speaker 03

  Not always, not everything, but there are things that happen to us early in life that are selected for early in life that cause aging.

• 36:00Chuck Nice?

  So the real deal is just keep having babies your entire life, uh, and then you'll never age. However, you will eventually kill yourself because of these kids.

• 36:13Speaker 03

  So we're an outlier, we're an outlier. We live about twice as long as we would based on our size.

• 36:21Neil deGrasse Tyson?

  But only post caveman life, right?

• 36:23Speaker 03

  Um, yeah, 40,000 years.

• 36:25Neil deGrasse Tyson?

  Exactly, so only, I mean, half of everyone died by 30, and so we're not 2X other mammals at our size, right?

• 36:33Speaker 03

  Yeah, and one last thing is, there's a group of animals, mammals, the bats, they live much longer, they're about the same size as a mouse, in terms of mass.

• 36:44Neil deGrasse Tyson?

  You're a flea or a mouse.

• 36:45Speaker 03

  They live about 10 or 20 times as long as a mouse. And the reason is, they can fly around. So that means two things, they can escape predators more easily.

• 36:57Chuck Nice?

  Right.

• 36:58Speaker 03

  And they can also forage over a much wider area for food. And, and when they roost, they roost in ceilings of caves, so they're not as accessible.

• 37:08Gary O'Reilly?

  They've been designed to survive longer.

• 37:10Speaker 03

  And so there is worth it for evolution to make them live longer, because they'll still keep producing more babies.

• 37:16Chuck Nice?

  Yeah, so you gotta be grandpa Munster, is basically the deal.

• 37:21Neil deGrasse Tyson?

  Grandpa from the Munsters.

• 37:22Chuck Nice?

  The grandpa from the Munsters, if you wanna live long. Sleep hanging upside down, away from predators.

• 37:27Gary O'Reilly?

  So, if we're looking at aging, we all do it, can't help it, more or less. What have been the attempts to reverse the aging, I'm not talking potions and lotions here, so let's go through the laundry list. The sort of young blood transfusion.

• 37:44Chuck Nice?

  Oh yeah.

• 37:44Gary O'Reilly?

  How successful has that been?

• 37:46Speaker 03

  It's not incredibly successful, but the science underlying it is solid. If you connect an old rat with a young rat, by that I mean you connect them so that their blood systems.

• 38:01Chuck Nice?

  Sharing the same circulation system.

• 38:03Speaker 03

  Exactly. Then it turns out that the old animal benefits from the blood of the young animal, but even more so, the young animal suffers from the blood of the old animal.

• 38:13Gary O'Reilly?

  Wow.

• 38:14Speaker 03

  And so, this means there are factors in blood that change as we age.

• 38:20Neil deGrasse Tyson?

  Such a thing as old blood.

• 38:22Speaker 03

  Exactly, or young blood, and that's why I call it vampire blood. So, that's the science, and, and the research is now about finding out what these factors are, what they do, and once you know that, you might be able to figure out whether you can use them to our benefit. But, people have not waited for that. What's happened is, the very first time these people from Stanford, Rando and others, published this, they got creepy phone calls from rich people asking you.

• 38:54Chuck Nice?

  Like Keith Richards.

• 38:56Speaker 03

  And, and companies started sprouting up, getting blood from young donors.

• 39:04Speaker 03

  And extracting the plasma and selling them up, you know, at $8,000 a pint or something to, you know, rich old people. And one of them, the FDA wanted to shut it down and then they sprouted up under a different name. And it's all, the whole thing was like the Wild West. But there's real science under it and, and, and that's an ongoing area.

• 39:24Gary O'Reilly?

  Okay, stem cells, we've kind of addressed as to how you can through the Yamanaka factors.

• 39:28Speaker 03

  Yeah.

• 39:29Gary O'Reilly?

  Dial up, dial down.

• 39:30Speaker 03

  And that's, I would consider that.

• 39:32Gary O'Reilly?

  Yamanaka.

• 39:32Neil deGrasse Tyson?

  What is the Yamanaka factor?

• 39:34Gary O'Reilly?

  The Oscar winning, where he sort of can.

• 39:36Neil deGrasse Tyson?

  You know that Oscar winning?

• 39:38Gary O'Reilly?

  Yes, Oscar winning. He was a bloody good actor. Unbelievably good actor.

• 39:42Neil deGrasse Tyson?

  Nobel Prize winner. Okay, that guy. Right, that guy. Thank you. Okay.

• 39:46Gary O'Reilly?

  The Nobel Prize.

• 39:47Neil deGrasse Tyson?

  Get your prizes straight here. Okay.

• 39:50Gary O'Reilly?

  The calorific restrict, or caloric restriction.

• 39:54Speaker 03

  Yeah, so.

• 39:54Gary O'Reilly?

  Which is basically fasting.

• 39:56Neil deGrasse Tyson?

  It is.

• 39:56Speaker 03

  It is. So lots of experiments, starting in mice, but now also in flies, worms, even in single-celled animals like yeast. If you reduce the amount of calories, it turns out that you can, the, the animals live longer, but more importantly, older animals start resembling younger animals in terms of their physiology and their biomarkers. And so the question is, can you mimic caloric restriction? And it turns out that there are many important biochemical pathways that are affected by caloric restriction. One of them is the IGF-1 insulin growth hormone factor.

• 40:38Neil deGrasse Tyson?

  Yeah. Just to be clear, what you're saying, you wouldn't have to imitate calorie reduction, you could just consume fewer calories. So, so what you're trying to do is, we can still eat our cheeseburgers and the blueberry pie dessert. And then you hijack what would be the starvation mechanism biochemically.

• 41:00Speaker 03

  Exactly.

• 41:01Neil deGrasse Tyson?

  That's intermittent fasting.

• 41:04Speaker 03

  Yeah.

• 41:04Neil deGrasse Tyson?

  But I don't have to fast.

• 41:06Speaker 03

  Is this the GOP?

• 41:07Chuck Nice?

  Oh, yeah, the whole point is not to fast, just to restrict you.

• 41:10Neil deGrasse Tyson?

  No, no, no, no. Did you get what I just said? No. What he's saying, that's why I paused on it.

• 41:15Speaker 03

  Saying, have your cake and eat it.

• 41:16Neil deGrasse Tyson?

  He did have your cake and eat it too.

• 41:19Chuck Nice?

  Yes, but explain your point again, because I missed it.

• 41:22Neil deGrasse Tyson?

  Okay, so the point is, what he said, he just slipped it in.

• 41:25Chuck Nice?

  Right.

• 41:26Neil deGrasse Tyson?

  But, but I caught him.

• 41:27Chuck Nice?

  Okay.

• 41:29Neil deGrasse Tyson?

  He's saying fasting, fasting will prolong your life.

• 41:33Chuck Nice?

  Absolutely.

• 41:33Neil deGrasse Tyson?

  So can we find a way to mimic the biochemistry of that in your body?

• 41:37Speaker 03

  We can.

• 41:38Neil deGrasse Tyson?

  And the word mimic in that sentence means still eat the cheeseburger.

• 41:41Chuck Nice?

  Right.

• 41:42Neil deGrasse Tyson?

  And but do what the fasting would have done to your biochemistry.

• 41:45Chuck Nice?

  I see, which, yes.

• 41:46Neil deGrasse Tyson?

  Have your cake and eat it.

• 41:46Chuck Nice?

  But you're doing it artificially, is what you're saying.

• 41:48Speaker 03

  I, in my book, I call it eating your blueberry pie and ice cream and, and getting the benefits.

• 41:54Chuck Nice?

  Nice.

• 41:55Neil deGrasse Tyson?

  And still getting the benefits.

• 41:56Chuck Nice?

  Wait, so have we done this?

• 41:58Speaker 03

  No, well, there are, there are some drugs.

• 42:01Chuck Nice?

  Okay.

• 42:01Speaker 03

  No, no, I'm, I'm not working on it.

• 42:03Chuck Nice?

  He's like, I'm out this game.

• 42:06Speaker 03

  I should say.

• 42:06Chuck Nice?

  He was like, did you see? Yeah, the way he said it. The way he just went like this, no, no, no, not me. They keep trying to keep me working. I'm telling you right now, I'm out.

• 42:15Speaker 03

  But if you do know how to do it, tell Chuck, because he'll set up a company.

• 42:18Chuck Nice?

  Certainly.

• 42:18Speaker 03

  No, lots of companies, that's a problem. So anyway, one of the drugs that does this is called rapamycin. It's a, it's the darling of the anti-aging research community.

• 42:30Gary O'Reilly?

  Find, isn't it?

• 42:31Speaker 03

  Easter Island.

• 42:32Gary O'Reilly?

  Yes.

• 42:32Speaker 03

  Easter Island is where it's coming.

• 42:34Chuck Nice?

  Yeah, rapamycin, okay, let's do it.

• 42:36Speaker 03

  Rapamycin was found in the soil of Easter Island in back, from bacteria in, in the soil of Easter Island that produced this compound, which turns out to be an antifungal compound. And then they found out that it may have some properties against cancer. And then eventually they found out that it actually is an immunosuppressor. And that's what made it get FDA approval as an immunosuppressive drug.

• 43:06Speaker 03

  Then, much later, it was found in a completely different place. It was found that it shuts down a major pathway in the cell. And that pathway is related to the... It's a pathway that senses nutrients. So it's related to caloric restriction. People then said, "Okay, let's see what happens if you give rapamycin to mice," and so on. And mice lived a bit longer, seemed a bit healthier. However, rapamycin is an immunosuppressive drug. So it's going to make you more prone to infections.

• 43:40Neil deGrasse Tyson?

  Like steroids.

• 43:41Speaker 03

  And it has other side effects as well.

• 43:43Neil deGrasse Tyson?

  Okay.

• 43:44Speaker 03

  So the question they have is, can you adjust the dosage so you get the benefits against aging without the problems of immunosuppression and so on? And that's still... Jury's still out on that.

• 44:00Neil deGrasse Tyson?

  Yeah. Okay, now, there's also relativity, where you can slow down time for yourself.

• 44:05Gary O'Reilly?

  Oh, well, that's going into space, though.

• 44:06Neil deGrasse Tyson?

  Yeah, well, right.

• 44:07Gary O'Reilly?

  That's one way to defeat aging, right?

• 44:09Neil deGrasse Tyson?

  However, you are still aging. Right. In your own body, one second per second. Right. The difference is, all your friends are aging faster than you. Much faster. Right, so you're not going to live older than you would have as an organism. Right. You'll just live longer than everybody else. Exactly.

• 44:24Gary O'Reilly?

  Isn't that the...

• 44:25Neil deGrasse Tyson?

  And then when you return, all your friends would have been dead. They'd be dead.

• 44:27Gary O'Reilly?

  The Kelly Twins, where they did the experiment.

• 44:29Neil deGrasse Tyson?

  Oh, yes, yes, we had one of them on this program.

• 44:32Gary O'Reilly?

  Yes.

• 44:32Neil deGrasse Tyson?

  Scott Kelly, astronaut who went up. That's right. And... His brother stayed here. Brother stayed here, they're identical twins. And you can calculate how much younger one would have been, like a fraction of a second. That's what he gained? He gained half a second, huh?

• 44:48Gary O'Reilly?

  Does it show?

• 44:49Neil deGrasse Tyson?

  So basically, yeah.

• 44:52Neil deGrasse Tyson?

  I don't remember the fraction, but it was... They were not going so fast that the speed of light...

• 44:57Gary O'Reilly?

  That's the definition of sibling rivalry.

• 44:59Neil deGrasse Tyson?

  Yeah. The most expensive anti-aging regimen ever.

• 45:24Neil deGrasse Tyson?

  So, as you surely know, in physics, we speak of this thing called entropy. Where left to itself, a system will always degrade to lowest energy, highest disorder.

• 45:41Speaker 03

  The key is left to itself.

• 45:43Neil deGrasse Tyson?

  Yes, yes, so, we can create any manner of complexity on Earth, because we're not a closed system. We're open to the sun. So the sun is gaining entropy by helping us out. Eventually, it's gonna die and nothing's gonna help it.

• 46:01Chuck Nice?

  Right.

• 46:01Neil deGrasse Tyson?

  Right? So, do you guys in molecular biology think of entropy?

• 46:06Speaker 03

  There's no question that entropic forces exist, but of course, living systems all use external energy to keep it alive. And part of the energy is used to do this maintenance and repair of the damage. But, it never, it's not perfect. And so, eventually, even if you keep repairing DNA damage, repairing cells, getting rid of defective cells, all of that stuff which takes energy, it's not perfect. And eventually, the system gradually decays. But it means it decays at different rates for different species.

• 46:42Neil deGrasse Tyson?

  Interesting. Or different parts, different systems, even within your own body.

• 46:46Speaker 03

  Oh, that's something that you, that, very interesting. So if you were to, people were to analyze your different organs, they'd find that they all had different ages.

• 46:55Chuck Nice?

  Yes.

• 46:56Speaker 03

  To say someone's biological age is a number...

• 46:59Neil deGrasse Tyson?

  Different ages mean different time distance from its birth to its death.

• 47:03Speaker 03

  Correct.

• 47:04Neil deGrasse Tyson?

  Right, because obviously, it's all, physically the same age.

• 47:07Speaker 03

  Physically, chronologically, chronologically, it's the same age.

• 47:11Neil deGrasse Tyson?

  Yes, but physiologically...

• 47:12Chuck Nice?

  Physiologically, they're at different ages. But it doesn't make a difference, because if I got an old heart and a young pancreas, I'm still gonna die.

• 47:19Neil deGrasse Tyson?

  With my heart issue.

• 47:20Chuck Nice?

  With my heart issue.

• 47:21Neil deGrasse Tyson?

  So that was always what I suspected, that people who live very long, all of their organs somehow are aging at the same rate. Physiologically.

• 47:31Speaker 03

  Well, I'm not, I don't know if that's true, but maybe they're still aging differently, but the lead organ, the organ that's aging fastest is still slower than other people.

• 47:41Neil deGrasse Tyson?

  Right, right. If they die, it's not gonna be from that. So, given what you just said, I didn't put two and two together here until just now. In the second law of thermodynamics, one of its stipulations is if you have sort of usable energy over here, and you convert it into another kind of energy over here, there's always energy losses, always. That's why you cannot make a perpetual motion machine.

• 48:07Speaker 03

  Right.

• 48:07Neil deGrasse Tyson?

  All right, and so, the body is all about converting energy of one kind into another. You have chemical energy in food, and you turn it into...

• 48:16Speaker 03

  ATP.

• 48:17Neil deGrasse Tyson?

  Yeah, exactly. Remind us about that. We all learned it in biology class. The ATP cycle, is that right?

• 48:23Speaker 03

  ATP is adenosine triphosphate. It's a molecule with high-energy bonds. So you can think of it as a universal currency, just like, in our world, electricity is the universal currency. So you use everything, convert it to electricity, then you can use that for everything. And so the body uses it, so you can think of it as a kind of storable form of energy that it can use.

• 48:48Neil deGrasse Tyson?

  Right, but it's taking energy from one, it's taking energy from one thing and...

• 48:53Speaker 03

  Right. Typically, in our case, we're getting it from carbohydrates.

• 48:57Neil deGrasse Tyson?

  Yes.

• 48:58Speaker 03

  And by burning carbohydrates.

• 48:59Neil deGrasse Tyson?

  So it's chemical energy.

• 48:59Speaker 03

  It's chemical energy.

• 49:00Neil deGrasse Tyson?

  Yeah.

• 49:01Speaker 03

  So that energy is used to make ATP.

• 49:04Neil deGrasse Tyson?

  Got it. And anything else we make in our body to maintain our body temperature, because we're warm-blooded, to move, so it goes to thermal energy, kinetic energy, and the like.

• 49:15Speaker 03

  And most of those things involve ATP.

• 49:19Neil deGrasse Tyson?

  And electrical energy. Right, for your brain and your heart, and signaling and all that. So I'm just saying, every time you convert from one form of energy to another, you're getting less energy than you started with. Right. So there is a decay in there.

• 49:31Speaker 03

  Yeah.

• 49:31Neil deGrasse Tyson?

  Eventually.

• 49:32Speaker 03

  Interesting, yeah.

• 49:33Neil deGrasse Tyson?

  So you describe this sort of implicit value of death to a species. Because it doesn't need you after a certain point of your fertility. We're beyond that now and we're what we call civilized. And so there are people who want to do anything they can.

• 49:51Chuck Nice?

  To stay alive for as long as they can.

• 49:53Neil deGrasse Tyson?

  To stay alive for as long as they can. And you're in that business scientifically. What is the ethics?

• 50:00Speaker 03

  I should say, my own lab has never worked on aging. I went from zero to expert in one book.

• 50:06Neil deGrasse Tyson?

  Oh, okay.

• 50:07Speaker 03

  Okay. My, my lab works on protein synthesis, which is a central component of aging. But I don't actually do aging research myself.

• 50:17Neil deGrasse Tyson?

  Okay, but surely you've thought about the ethics of it.

• 50:20Speaker 03

  Yeah.

• 50:20Neil deGrasse Tyson?

  Why wouldn't you have?

• 50:21Speaker 03

  Oh, definitely, yeah.

• 50:21Neil deGrasse Tyson?

  Yes, yes.

• 50:22Speaker 03

  And I also have no skin in the game, so that's a...

• 50:25Neil deGrasse Tyson?

  Okay.

• 50:26Chuck Nice?

  That means we can get a very, a truly objective...

• 50:28Neil deGrasse Tyson?

  Other than beautifully soft skin.

• 50:30Chuck Nice?

  Right.

• 50:32Chuck Nice?

  I missed that one.

• 50:33Neil deGrasse Tyson?

  Yeah, Chuck, I don't want to be ahead of you on any of this.

• 50:36Chuck Nice?

  That was a good callback. I like it.

• 50:38Gary O'Reilly?

  Chemical laws, biological laws? Any in the way to stop us going from where we are now to potential immortality?

• 50:45Speaker 03

  Right, so there are two issues. One is, is aging programmed? I mean, are we all programmed to die?

• 50:50Gary O'Reilly?

  Yes.

• 50:51Speaker 03

  No, because evolution doesn't care about...

• 50:53Chuck Nice?

  It doesn't care about us dying.

• 50:55Speaker 03

  So there are genes that affect aging, but those genes don't exist in order to make us age. They were selected for some other reason, but they happen to cause us to age. So now that we understand some of the biology of aging, you ask, can we extend that?

• 51:11Gary O'Reilly?

  Yes.

• 51:12Speaker 03

  And there's no, there are no physical or chemical laws that say that we have to die at 120. I mean, 120 is about the record for humans.

• 51:24Chuck Nice?

  Right.

• 51:24Speaker 03

  Very few reach that.

• 51:25Chuck Nice?

  And by the way, whenever you see a 120-year-old, they're like, "I am ready to go."

• 51:31Speaker 03

  Oh, I'm not sure.

• 51:32Neil deGrasse Tyson?

  It's like, "Don't take me to Disney World."

• 51:36Chuck Nice?

  Not all of them, but yeah.

• 51:37Speaker 03

  There's a woman, Jeanne Calmont, who's the record holder at 122.

• 51:41Gary O'Reilly?

  Oh, she was the smoker and drinker.

• 51:42Speaker 03

  She was, she used to smoke and drink into our hundreds. And, and reporters, after a while... Used to gather at our house every birthday. And one of the reporters said, well, see you next year, I hope. And you know what she said?

• 51:57Neil deGrasse Tyson?

  What?

• 51:57Speaker 03

  She said, sure, why not? You look pretty good to me.

• 52:03Speaker 03

  But there's no physical or chemical law that says, you know, at 120.

• 52:09Neil deGrasse Tyson?

  You gotta go.

• 52:10Speaker 03

  You gotta go. There are species, as I said, that live 700 years, vertebrates. Of course, the question is, can we change our biology to make us live much longer? And still keep us humans? You don't want to be a very slow metabolic animal like a Greenland shark. You still want to be human and you still want and you want to live much longer. Now, there are people, I would say, at the one end of the anti-aging research community, including perhaps somebody you've had on your show, who think that it's it is possible. You can just keep extending life and that'll buy you enough time to do more research and you'll extend more life.

• 52:53Neil deGrasse Tyson?

  And we eventually, there's a generation that would reach the escape velocity.

• 52:56Speaker 03

  Exactly.

• 52:56Neil deGrasse Tyson?

  Where the prolonging of your life is one year per year. And then you live forever.

• 53:02Speaker 03

  Yeah, now, I I'm highly skeptical, as are most scientists in this field. Because aging is a is a multifactorial process. And to be able to do this in a way that's safe, that's efficacious, that actually works, I think is is going to be very, very hard. Certainly not impossible.

• 53:22Neil deGrasse Tyson?

  The Google software that uses AI for folding proteins, which won a Nobel Prize, if if memory serves. Won't that solve all your protein folding problems?

• 53:33Speaker 03

  No, this is this is different from. I I think AI will have a big influence on biology. And maybe one day it will help with things like aging.

• 53:44Neil deGrasse Tyson?

  One day, 18 months from now. Some time in the distant future. In the future, distant future of AI.

• 53:50Speaker 03

  What time is it?

• 53:53Speaker 03

  Let's say I'm highly skeptical, but there is no physical law. But I'd say there's also no physical or chemical law that says you can't colonize other galaxies, or even Mars. And so, you know, whatever Elon may say, it's not gonna happen tomorrow. So I think-

• 54:13Chuck Nice?

  And I think we should get down here, kinda worked out first. I'm sorry, but yeah, why don't we make this place habitable?

• 54:20Neil deGrasse Tyson?

  Alright, so what happens the day we as chiefs escape velocity? What happens to civilization?

• 54:25Speaker 03

  I think before that, a number of things will happen. For example, more people may live to be a hundred, or well into their nineties or early hundreds. That itself will cause a huge shift in society. For example, fertility rates everywhere are dropping. And so what you're gonna have is-

• 54:46Neil deGrasse Tyson?

  It's an aging of the population.

• 54:47Speaker 03

  Yeah, society where there's very little turnover. Same people are living longer and longer, very, very slow turnover. To me, that means a less dynamic, less vibrant society. If you look at the history of science, or any fields, even literature, people have done their most creative work when they're young. And it's not just about physiological age. When you're young, you're looking at things fresh, you're not as opinionated, you're not dogmatic, and that allows you to think out of the-

• 55:22Neil deGrasse Tyson?

  You have to convince the old people that they're less useful to society. How do you do that?

• 55:26Speaker 03

  Well, one of the reasons I'm retiring is because, you know, I decided four or five years ago to close down my lab. It's gonna happen late this year. It's partly because I do believe that when you've had your time, you know, you should step aside and let younger people carry on.

• 55:46Chuck Nice?

  Carry on.

• 55:46Neil deGrasse Tyson?

  When Einstein was given the option to be operated on, basically on his deathbed, he said, "No, my work is done."

• 55:53Chuck Nice?

  My work is done. Yeah, I would've said, "What kind of doctors are you? Save me."

• 56:00Gary O'Reilly?

  What you were talking about is inverting the population pyramid. So it goes from a small peak of aging population to a rather large one and less young people. We are basically diving down a drain here.

• 56:11Neil deGrasse Tyson?

  Well, it would be, it would be, it would be more stable the whole time.

• 56:14Speaker 03

  More stable. Stable thing would be good, but if the turnover is very slow and people just live for very long. I mean, as people get older, they accumulate power, they accumulate wealth, they accumulate influence. And of course, the three go together. And that then means that it's harder for younger people.

• 56:36Neil deGrasse Tyson?

  To gain entrance.

• 56:37Speaker 03

  To gain entrance, to make it and so on.

• 56:40Neil deGrasse Tyson?

  Sococultural fact.

• 56:43Speaker 03

  And that's a, that's a, that's a real problem.

• 56:46Chuck Nice?

  We're seeing that right now in a certain party in, in America where they're like, yo, everybody who is in charge is 80 years old, get out of the way because we have a different way to do things and we want to get to it.

• 56:59Speaker 03

  And so, so I think societies would be more stagnant and less dynamic and less creative. People will always throw exceptions at me. Oh, so and so was so brilliant, old and late in life. But those are exceptions, you know, that's not what you plan a society around. But here's the problem. If somebody gave you a pill and said, this is going to give you 10 extra years of healthy life. Nobody wants to be sick for 10 years. 10 years of extra healthy life. Would you take it? I know I would.

• 57:31Chuck Nice?

  Yes.

• 57:32Speaker 03

  Okay. Almost all of us would. And this is the conflict between what we as individuals want and what's good for society.

• 57:39Neil deGrasse Tyson?

  Right. Because at the end of those 10 years, if you're given the option again, you'll probably say yes again.

• 57:42Speaker 03

  Exactly.

• 57:43Chuck Nice?

  Absolutely. Especially if it's healthy life.

• 57:46Neil deGrasse Tyson?

  So that thought experiment takes the larger question down to its individual parts and you realize people really do want to live forever.

• 57:54Chuck Nice?

  They do, well, because yeah.

• 57:55Speaker 03

  They do. Because this is, as you say, the only life we know. It's our existence. We, we fear the, the loss of existence. And that's, that's the problem.

• 58:05Chuck Nice?

  But you know, there's, I mean, I'm about to get philosophical. The great thing about death is that when you look at it full on and embrace it for what it is, it allows you to wake up and... Treat each day as something special because you know this thing is going to be over. If you take that away, you know, I don't give a damn.

• 58:27Speaker 03

  People have said that, that having a finite life gives you the drive, the incentive to accomplish things. Otherwise, there's always tomorrow.

• 58:36Chuck Nice?

  There's always tomorrow.

• 58:37Speaker 03

  Okay, so that that is true, but at the same time, there's all, there's an old joke. Who would want to live to be a hundred? And the answer is always someone who's ninety-nine.

• 58:45Chuck Nice?

  Exactly.

• 58:48Speaker 03

  So you may, you may be philosophical about death in the abstract, but you don't want to die next year.

• 58:53Chuck Nice?

  Well, no, yeah, you're absolutely right. I don't want to die, period, you know, because my life is pretty damn good. So, you know, as long as.

• 58:59Neil deGrasse Tyson?

  And we're not talking about people who are so mortally injured or, or ill that death feels like an escape. We're talking about someone who's fully.

• 59:09Chuck Nice?

  Who's vibrant.

• 59:10Neil deGrasse Tyson?

  Vibrant, yes.

• 59:10Speaker 03

  There's also one aspect of aging research. If you tell, if you ask most of them, they, they'll say, except for some of these outliers, they'll say, oh, we're not about extending lifespan. We're about increasing health in your life. And the idea is that you stay healthy all your life and then suddenly, you know, crash and die. And there's a poem called The One Horse Open Shay.

• 59:32Neil deGrasse Tyson?

  I just learned about that poem. It's, it's the horse that.

• 59:36Speaker 03

  The carriage was perfectly designed so that it wore out it, all its parts wore out equally.

• 59:42Neil deGrasse Tyson?

  Exactly at the same time.

• 59:43Speaker 03

  And one, one minute the farmer was riding along, the next minute he was on the ground, surrounded by a bunch of debris. Because his whole carriage collapsed. Now that's what people are, are asking when, when you say, we're going to compress the period of morbidity in old age. And we're just going to suddenly decline and die. Nobody's shown that that can actually happen.

• 1:00:07Chuck Nice?

  Uh, Apple is working on it, believe me.

• 1:00:10Speaker 03

  Nobody's shown that, so if they increase our health span, it's equally possible that they may extend.

• 1:00:17Neil deGrasse Tyson?

  Good phrase, not lifespan, health span.

• 1:00:19Speaker 03

  Yeah, but if they do that, if they keep us healthy in old age, it's equally possible that they extend our lives too. And that eventually we still have that slow decline.

• 1:00:30Neil deGrasse Tyson?

  You still have the.

• 1:00:31Chuck Nice?

  You just reach a point where now I'm a hundred and eight and it's all falling apart, but I'm not going to die tomorrow. It's still going to be a slow, hard, most death five years from now.

• 1:00:39Neil deGrasse Tyson?

  Yeah. Of course, if we live forever, we need to find another planet because the population will continue to rise. And we will outstrip the resources of Earth. And possibly Mars, Venus, and anyplace else we search for.

• 1:00:52Speaker 03

  That isn't quite true.

• 1:00:53Neil deGrasse Tyson?

  What? Well, okay, if birthrate went to zero, then it's not a problem.

• 1:00:59Speaker 03

  Exactly.

• 1:01:00Neil deGrasse Tyson?

  But who wants that?

• 1:01:01Speaker 03

  Well, first of all, you're not gonna have complete immortality. You're going to have extended lifespan. So the birthrate simply has to fall in accordance with how much you've increased your lifespan.

• 1:01:12Neil deGrasse Tyson?

  There you go.

• 1:01:12Speaker 03

  And in fact, if you look at Korea, South Korea.

• 1:01:16Neil deGrasse Tyson?

  It's happening anyway.

• 1:01:17Speaker 03

  It's happening. People are living longer, and yet the population's going down.

• 1:01:23Neil deGrasse Tyson?

  So Venky, this conversation has been delightful and illuminating and enlightening. I can't wait to die.

• 1:01:33Neil deGrasse Tyson?

  And after we're done with this episode, he's gonna whisper to us that he's 150.

• 1:01:42Neil deGrasse Tyson?

  On this topic of why we die, we covered so many nuances of it. I'm left with very little to offer as a cosmic perspective. What I will say is that, speaking for myself, I, at this stage in my life, value the knowledge that I will die. Because that gives meaning to every day that I'm alive. Knowing that there's one fewer days left in my future. To love, to have new ideas, to make discoveries,

• 1:02:23Neil deGrasse Tyson?

  to embrace all that it is to be alive in this world. If you look at it mathematically, if the knowledge of death is what brings meaning to being alive, then to live forever is to live a life with no meaning at all.

• 1:02:46Neil deGrasse Tyson?

  If you can just put off to tomorrow what you could have done today. Will I think this on my deathbed? If I'm offered a pill that can make me live another 10 years? When I'm on my deathbed, would I take that pill? I don't know. It's kind of easy to talk about death when I'm pretty sure I'm not near it in this moment. But I will say, I reserve the right to revisit the option of living a little longer when I'm on my deathbed. But for now, knowing I'm gonna die is what's keeping me going. And that is a cosmic perspective. Chuck, good to have you, man. Always a pleasure. Gary. Pleasure, my friend. All there.

• 1:03:30Neil deGrasse Tyson?

  This has been StarTalk Special Edition. Topic: Why We Die. Until next time, Neil deGrasse Tyson, your personal astrophysicist. Keep looking up.