October 29, 2025 • 33 mins
Bears, squirrels and birds (oh my!) can do it, but can humans? Jorge explores how this technology could be a game changer for medicine and space travel.
See omnystudio.com/listener for privacy information.
Mark as Played
Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:00):
Hey, please take a second and leave us a review
on Apple Podcasts, Spotify, or wherever you listen to the podcast.
Thanks a lot. Hey, welcome to Science Stuff, a production
of iHeartRadio. I'm hort Jam and today we're answering the
question can we hibernate humans? We know bears can do it,
some birds can do it, and even lemurs can do it.
(00:23):
But could we get a person to hibernate? And would
it lead to breakthroughs in emergency medicine, cancer research, and
even space travel. We're gonna talk to a biologist who's
been studying hibernation in animals for thirty years, as well
as a medical researcher who's been working with the European
Space Agency to see if this would let humans travel
(00:44):
to distant stars. So get nice and cozy and get
ready to enter a state of science torpor as we
answer the question can we hibernate humans? Hey? Everyone do?
They were asking three questions, what is hibernation, can we
(01:06):
get it to work in people? And why would we
want to hibernate a person? It turns out there are
a lot of reasons why we would want to do that,
including maybe letting us explore the cosmos, but first we
need to understand what it is and how animals are
able to do it. So my first conversation was with
Professor Kelly Drew.
Speaker 2 (01:29):
So, my name's Kelly Drew. I am a professor at
the University of Alaska, Fairbanks, and I direct a NIH
funded center called the Transformative Research and Metabolism. So I've
studied hibernation for about thirty years, so I'm very much
focused on the brain and hibernation.
Speaker 1 (01:46):
Incredible. I think you're the perfect person for us to
talk to you today.
Speaker 2 (01:49):
Awesome.
Speaker 1 (01:50):
Maybe start us off, how do you define hibernation? What
is it?
Speaker 2 (01:53):
Well, the big picture of hibernation is that it's a
metabolic adaptation where it suppresses metabolism and body temperature because
sometimes they need to conserve that energy if food is
not available, and many animals do it. Everything from some primates.
There's the fat tailed lemur from Madagascar. There's marmots. Bears hibernate,
(02:15):
not polar bears. Polar bears don't hibernate because they have
food year round because they fish off the ice, but
black bears and grizzly bears hibernate. And then there's ground
squirrels and hamsters, even the common house mouse. If you
take its food away, it will hibernate. Hummingbirds will hibernate.
Speaker 1 (02:35):
Hummingbirds.
Speaker 2 (02:36):
Yeah, there's a lot of different species.
Speaker 1 (02:40):
Yes, hummingbirds hibernate too. Okay. The big question I had
for doctor Drew was how is hibernation different from sleep?
Speaker 2 (02:49):
Actually is thought to be an extension of sleep, So
at least with hibernation, animals have to sleep to enter hibernation.
And what I think is that there's a process that
kind of flips a switch that allows the temperature to
continue to cool, and then cold by itself plays a
role in suppressing metabolism.
Speaker 1 (03:10):
So hibernation is not just sleep. Something else kicks in
in animals during hibernation, and that causes two things to happen.
One through metabolism, meaning how active the cells in their
body are slows down. And two, their body temperature drops.
And this is a key feature of hibernation because normally
(03:31):
your body doesn't let your body temperature go down. Even
when you sleep, your body doesn't drop below one or
two degrees of its normal temperature. It's all part of
our survival mechanism.
Speaker 2 (03:44):
We all have a point where if we get to
a certain temperature, our bodies kick in the keaters, humans
will shiver, we start generating heat. And so the trick
is that during hibernation, your body allows it to get
a little bit colder than what we normally do. So
it's often thought of as well, you just lower the thermostat,
reset the set point on the thermostat, and you get
(04:06):
down to a colder temperature, and that temperature helps to
suppress metabolism. So you go into this kind of state
of nirvana, very low energy consumption, and everything just sort
of quiets down.
Speaker 1 (04:18):
I see. So once we go into tibernation, our set
point is set lower, and so the body gets colder
and that doesn't do any harm to the organism.
Speaker 2 (04:27):
Well, the ground squirrel is especially adapted to cold tissue temperature.
For humans, if our bodies go below about thirty degrees celsius,
then we can have cardiac arrhythmias, so the heart doesn't
function all that well. But the ground squirrels are specially
adapted and their body temperature goes down actually to minus
three degrees below freezing, wow, minus three celsius, and they
(04:49):
have no trouble with that.
Speaker 1 (04:53):
So Hibernation isn't just about slowing your heart rate or
going to sleep for a long time. Something really fundamental
happens to animals that hibernate. Their entire bodies recalibrate to
work at a lower temperature, which is something that normally
our bodies very strongly rejects. I mean, if you go
below thirty degrees celsius or eighty six degrees fahrenheit, as
(05:16):
doctor Drew said, your heart basically stops working. But animals
that hibern need have a special mechanism that lets them
run super cold.
Speaker 2 (05:26):
And so the ground squirrels have adapted these temperature mechanisms
so they keep things functioning even in the cold. I
mean the same thing in your car. You know, you
change the weight of your oil for winter compared to summer,
so you want a little bit less viscous oil in
the winter.
Speaker 1 (05:41):
I see, I live in California and I'm from Panama,
so this is need to me, that's the in fact
that you need to change your oil. But in Alaska,
I imagine that's a common thing.
Speaker 2 (05:51):
Very common. Yes, So all those kinds of things. Animals
have adaptations that allow them to tolerate different temperatures, and
we don't know really what all those are.
Speaker 1 (06:03):
Okay, here I had a lot of questions for doctor Drew,
like what's happening in the brain of these animals when
they hibernate, Do they dream or are they conscious? What
triggers this hibernation mechanism? And then what's going on in
the brain while animals are in the state.
Speaker 2 (06:20):
Well, like I said, they are first sleeping, but as
they cool, the magnitude of the brain waves they shrink
and get lower and lower as the animal cools, until
finally it becomes flat. And that actually looks somewhat like
being in a coma, but they're not in a coma
because they can be induced to arouse just by handling.
Speaker 1 (06:42):
But it's more extreme than sleeping for example.
Speaker 2 (06:44):
Right, Yeah, it's a different state of consciousness. So cold
really continues to dampen the brain waves so that then
they will become flat.
Speaker 1 (06:54):
Meaning like the brain doesn't work at those lower temperatures.
Speaker 2 (06:57):
You don't see any electrical activity.
Speaker 1 (06:59):
That means, so basically the brain of the animal stops working.
It's almost being brain dead, but not quite. In fact,
it's something very different. Amazingly hibernating animals have been shown
to be able to learn while they hibernate.
Speaker 2 (07:18):
And they can learn actually when they're in this state.
Speaker 1 (07:22):
Wow, what do you mean they learn? How can they
learn if they're passed out?
Speaker 2 (07:25):
What they learn is they habituate to handling. If you're
like needing to do something with the animal when they're
in hibernation, you can just handle them, and at first
they'll be bothered by it, and they'll start to wake up.
And if you do that over and over, they pretty
much get used to it to where they just don't
bother anymore. They're used to it. If you go in
and handle them, they won't arouse. Wow, And so we
(07:48):
consider that to be learning. It's called habituation.
Speaker 1 (07:50):
Oh wow, that's uds like my teenage son when you're
trying to.
Speaker 2 (07:56):
That's exactly it.
Speaker 1 (07:59):
Yeah, even though their brain activity is totally flat and
they seem like they're in a coma or brain dead,
the hibernating animal can still somehow process what is happening
to it. It's really a very different state of being. Okay.
The next question I had was what triggers hibernation.
Speaker 2 (08:18):
We've got animals that hibernate according to season. We call
them obligate hibernators. So they have a clock in their
bodies that tell them what time of year it is,
and no matter whether it's cold or dark, or whether
they have food or don't have food, they will hibernate.
And those are the ground squirrels and other species like
the hamsters are what are called facultative hibernators, and for those,
(08:42):
the hibernation has to be induced by short days, so
like what you would see in winter. Other animals like
mice will hibernate just because they don't have food. It's
just simply, hey, we don't have any food. Let's chill
for a while as long as we can, and then
we're gonna warm up again. See if there's any food.
Speaker 1 (09:01):
Oh, I see, let's just wait it out and see
what happens. Yeah, what about like bears.
Speaker 2 (09:05):
And bears are a little bit more facultative because if
it's warm, they won't hibernate. If they have a whole
lot of food, they don't hibernate. So bears, because they're
so big, they don't actually get that cold. They don't
get colder than about thirty degrees see, but they suppress
their metabolism down to twenty five percent of basil metabolic rate.
(09:26):
So basil metabolic rate is as low as you can go.
Speaker 1 (09:30):
If you go lower, you're dead.
Speaker 2 (09:31):
Kind of, yeah, you're dead.
Speaker 1 (09:33):
Would you say? That's kind of a definition of hibernation
is let you basically slow your body down to where
you would normally be.
Speaker 2 (09:40):
Dead, exactly right. And lots of people like to think
of it as near death, and that way is very similar,
and we like to imagine that hibernation is a state
that kind of is near death, but it can be reversed.
Speaker 1 (09:57):
All right, When we come back, we're going to talk
about another interesting fact site to sit found about hibernation,
and then we're going to talk about whether we could
ever make it happen in humans. Don't go anywhere, we'll
be right back. Hey, welcome back. We're talking about hibernation
(10:28):
and whether we could ever do it in humans. And
so far we've learned what hibernation is, which animals do it,
what triggers it, and whether animals dream while they hibernate.
The last thing we're going to talk about before we
get to hibernation humans is that hibernation in animals is
not constant. There's a cycle in hibernation.
Speaker 2 (10:50):
And for whatever reason we don't understand animals when they
go colder than thirty degree c they have to rewarm
every so often. Hamsters will rewarm every three to four
five days. Ground squirrels rewarm every two to three weeks,
and we call these interbout arousals. And during that interbout arousal,
they sleep, so the flat eeg turns into slow wave sleep.
(11:11):
They make glucose, they urinate just a little bit, they
fluff up their nest, and they sleep and then they
re enter torpurth.
Speaker 1 (11:20):
Torpor, by the way, is what scientists call that deep
low metabolism, cold temperature, almost brain dead state animals enter
during hibernation. But what doctor Drew is saying is that
animals are not in that state the whole time. They
kind of stir and kickstart their body every so often
throughout the hibernation period, and scientists think animals do this
(11:42):
to kind of do body maintenance.
Speaker 2 (11:46):
Something initiates that in about arousal. That evidence suggests that
it's either an accumulation of something a waste that they
have to get rid of, or a lack of metabolite
that they need, like for example, glucose and so they
need to make glucose and they can't do it when
they're cold. So during hibernation, they may need to warm
(12:06):
up to make glucose. They may need to warm up
to get rid of nitrogen somehow, And so that's what
we think is that they have to warm up periodically
to do some of that metabolic work.
Speaker 1 (12:18):
So you're saying built into hibernation is this sort of
periodic arousal where they do a little bit of maintenance
and then they go back to hibernation.
Speaker 2 (12:27):
That's right, that's right.
Speaker 1 (12:29):
All right, And now we get to the topic of
making humans hibernate. And the first question you might have
is why hibernate a human? Well, according to doctor Drew,
there are many reasons why we would want to put
humans in a deep state of torpor. Okay, why would
we want to hibernate humans?
Speaker 2 (12:47):
Well, the most lowest hanging fruit is for critical care,
particularly for brain injury. Like if you have a cardiac
arrest that means like sudden heart failure, you fall on
the ground and now you're comatose and you get resuscitated
by CPR. Those people actually wouldn't know it, but they
ultimately die from brain injury. So even though they can
bring them back, the brain doesn't tolerate that lack of
(13:10):
blood flow very well. So if we can induce hibernation,
there's potential that it could have immediate benefit to people
that suffer stroke or cardiac or risk drowning or lack
of oxygen.
Speaker 1 (13:22):
How would that help them, Well, it may.
Speaker 2 (13:24):
Just simply prevent the injury caused by the lack of
blood flow, or it could stabilize the injury while every
other processes kind of come back to normal and then
allows the body to kind of deal with it at
a slower pace at a better time.
Speaker 1 (13:39):
Meaning you just want to slow everything down so that
the injuries don't get worse.
Speaker 2 (13:43):
Yes, right, having them enter this hibernation natural cooling state
is expected to be more beneficial.
Speaker 1 (13:50):
I see. So that's one reason we might want to
hibernate a person in an emergency. Going into hibernation could
cool the body down going into hypothermia, and that would
slow the response to the body so that doctors have
more time to deal with the injury. And this could
be useful not just in heart attacks and strokes, but
(14:11):
in any kind of injury where medical care is not
easy to get.
Speaker 2 (14:16):
So you could stabilize somebody by putting them into a
hibernation state, and how you can get them to medical facilities.
It certainly battlefield operations. Same with remote emergency care. If
somebody falls mountain climbing or whatever and is injured but
they can't be evacuated for a period of time, they
could be stabilized by putting them into these states.
Speaker 1 (14:38):
And another interesting reason to hibernate people is to maybe
save the planet, he said, saving the planet. What's the
scenario there?
Speaker 2 (14:47):
So the other kind of grandiose ideas I've heard. One was, well,
we can save the planet if you know, we can
just all chill on a regular basis. We don't drive
as much, we don't use as much electricity, all these things.
Speaker 1 (15:01):
Like we would all go into hibernation every once in
a while or every night or what do you mean?
Speaker 2 (15:05):
Yeah, maybe for you know, like life holidays, Yeah, a
couple of weeks at a time. I think it was
inspired by COVID a little bit, because as horrible as
it was, we definitely saved some things. You know, traffic
was less and pollution lowered, wasn't so bad. People get
(15:25):
pretty engaged in the life and hard to say, well,
I'm just going to cut out for a couple of
weeks or a month.
Speaker 1 (15:32):
Yes, we could take hibernation vacations. Say you just want
to check out for a few days or a few months,
you could hibernate, and overall we would reduce human activity,
which could be good for the planet. I mean, how
many of us would like to take a break right
now and not wake up until the next presidential election.
And doctor Drew says taking hibernation vacations wouldn't just reduce
(15:54):
your carbon footprint, it could actually help you dage and
live longer.
Speaker 2 (16:02):
But what's interesting and hybridating animals is they do live longer.
Hibernation prolongs life, but you just kind of a pause.
It's not the wear and tear on the body. You're
really taking a break and cooling and rewarming. There's evidence
that it has some regenerative properties, so you can actually
you know, regenerate synapses, potentially regenerate muscle. But certainly in
(16:24):
hibernation is interesting because even though they don't eat or
move for eight months, they wake up strong. Whoa, they
don't lose any muscle.
Speaker 1 (16:33):
So they live longer, not just because they pause their body.
But because there's other benefits to hibernation.
Speaker 2 (16:40):
There could be that's still a hypothesis, but we're seeing
evidence of cold and rewarming. The combination of cooling and
rewarming stimulates regenerative processes.
Speaker 1 (16:50):
I see. You would think that it's just your body
kind of goes downhill when you're hybrided. But now there's
something stimulating about hibernation. Yeah, fascinating.
Speaker 2 (16:59):
But you know it's also a wonderful weight loss program.
Speaker 1 (17:03):
What do you mean, what do you mean.
Speaker 2 (17:04):
Well, you don't eat, metabolism is down These ground squirrels
can double their body weight pre hibernation and then they
lose all of that by spring, but they're fit and
trim when they wake up.
Speaker 1 (17:16):
Oh wow, that does sound like a really good program.
Well I am all in on that startup. Right, that's
Fitness Life Extension. Where do I sign a check for
that investment?
Speaker 2 (17:31):
Exactly?
Speaker 1 (17:33):
That's right. You could use hibernation to lose weight during
hibernation and the most burnt fat to stay alive. And
so you could imagine going into hibernation for a while
and waking up thinner without having to diet or exercise. Okay,
the last super interesting reason to hibernate people is for
space travel. You've all seen the science fiction movies where
(17:55):
astronauts climb to a sleeppond and going to suspended animation.
But why is that? How does hibernation help with goin
as space? To find out, I talked to a medical
researcher that's been working with the European Space Agency on
this idea. Well, thank you, doctor Huk for joining us.
Speaker 3 (18:13):
It's my pleasure. I'm very curious a lot your questions
and to explore with you together, you know, the new
perspectives of potential hibernating humans.
Speaker 1 (18:21):
One day, can you please tell us who you are
and what you do.
Speaker 3 (18:24):
I'm a physician by training during research and mostly about
organ protection, which has brought me to this field of
spaceflight and how the organisms reacting to extreme environments.
Speaker 1 (18:35):
Okay, now, according to doctor Chuk, there are several reasons
why being able to hibernate would help humans travel through space. Now,
you probably think the main reason is the one you
see in movies, which is that space is huge and
it takes a long time to get anywhere. For example,
the near start to us Proximus centory is forty trillion
(18:57):
miles away and getting there could take hundreds or even
thousands of years. So being able to climb to a
pod and somehow good sleep and stop aging means you
could actually survive the trip. This is true. But actually
NASA and the European Space Agency are interested in hibernation
for more practical reasons, and they're looking at it as
(19:19):
a strategy for shorter journeys like say to Mars. Getting
to Mars takes a little less than a year. So
why would we need to hibernate? Well, like I said,
there are several reasons, and the first is that when
you're hibernating you don't need to eat as much. You said,
there are big advantages in terms of resources. Can you
(19:40):
explain what that means?
Speaker 3 (19:41):
Yeah, we did a study with the European Space Agency.
We designed the mission of six people going to Mars
and back just theoretical design. What do would that mean?
How much resources do we need? How much oxygen, how
much water supply, food supply, so on. What would be
the scenarios of being under hibernation condition versus another high
condish And of course oxygen you save a lot, but
(20:03):
the most tracking element is for food. For instance, you
have maybe a twenty percent of fifteen percent of food needed.
Speaker 1 (20:10):
Only Doctors huqu In the European Space Agency calculated that
for a six percent mission to Mars, where everyone stays
awake the whole time, you need to bring about six
tons of food, which is six thousand kilograms or about
thirteen thousand pounds of food. And that's because the whole
trip would take about two years, and so you need
(20:32):
over two thousand, two hundred meals for six adults, and
there are no grocery stores along the way, so you
have to bring everything. But then they compared that to
a Mars mission in which the crew hibernated some or
all of the way there and back, and the amount
of food you need in that case turns out to
be only seven hundred kilograms, or about fifteen percent of
(20:54):
the original amount. That's about five tons of payloads that
you don't need to bring. If you hibernate the crew,
you only need sixty seven hundred kilograms.
Speaker 3 (21:05):
Wow, exactly. This makes the difference. And when you just
think about the implementation of a travel to Mars, you
just need less payloads. Yeah, so this is why agencies
maybe like it. Yeah, yes, we reduce the payloads. You
need less stuff to get uploaded, and every kilochrome every
pound costs a lot of money.
Speaker 1 (21:24):
So hibernation would make space travel cheaper. Another reason hibernation
would help going to space is that hibernation apparently makes
you more immune to radiation damage. Space is full of
harmful radiation, some of which comes from the Sun and
some of which comes from cosmic rays, but it's a
(21:45):
real problem for astronauts. It means that your chances of
getting cancer out in space are much higher than if
you stay on Earth. But for reasons that scientists aren't
quite sure of, going into hibernation makes you more radiation.
Speaker 3 (22:03):
When you relief of vicinity and go the younger fun
old belt and having less protection, you will see more
radiation effects there it will increase, and depending on solar eruptions,
this may even be detrimental. So radiation resistance is a
big thing.
Speaker 1 (22:19):
Doctor Chuke says that scientists in Germany and Italy have
done experiments where they induce torpor in test animals and
they found that it kind of protects them from radiation damage.
And the reason for that is not quite clear to scientists.
Some think it's because your cells are not multiplying as much,
so there's few chances for the radiation to cause inmutation.
(22:41):
But it could also be because during hibernation, the body
is better at repairing itself. And this brings up another
reason hibernation could help in space travel, and that is
what we mentioned before in animals. When animals hibernate, they
don't lose bone or muscle mass. Hibernating animals wake up
trim and fit and ready to go. But human bodies
(23:03):
when they're in space start to go downhill and deteriorate fast.
Speaker 3 (23:10):
When you stay lower in space, the problems may really
kick off. It might be either the conditioning of the
body so you're not experiencing gravity, pull on your bone,
on your muscle, so you get rid of some volume
that you don't need. The bones are gone muscles. Yeah,
there was a research paper summarizes you need a new
skeleton in the closet when you leave this even when
you survive. But because your bones get really weak because
(23:33):
of this deconditioning effect that you don't challenge your body.
And if you had the chance to put someone in hibernation,
these degenerated processes would stop, yeah, or would be wow,
maturely reduced.
Speaker 1 (23:46):
I hadn't thought about that. So we've seen that in animals.
Animals don't lose bone or muscle.
Speaker 3 (23:52):
Exactly, they don't lose bone and muscle and wake up
and up back to the business.
Speaker 1 (23:56):
So to say, clearly, being able to hibernate humans would
be a game changer for space travel. You could imagine
hopping on a spaceship going into hibernation, and when you
wake up, you're in Mars, and not only are you
well rested and less damaged by radiation, but you feel great,
maybe even in better shape than when you went to sleep.
(24:19):
So now the question is can we actually do it
in humans? Is it actually possible to hibernate people? When
we come back, we'll ask our two experts this question.
We'll find out what scientists have done to make this happen.
Don't go anywhere, we'll be right back, and we're back.
(24:53):
We're talking about the possibility of hibernating humans, and so
far we've talked about how hibernation worksimals and what are
some of the reasons we would want to make it
happen in people. It could help with emergency medicine, producing
our carbon footprint and may even have health benefits. It
could also be a game changer for space travel. We
(25:14):
heard from doctor Alexander Chuquet, a physician that works with
the European Space Agency, on what space does to the
human body, and he listed some of the advantages hibernation
could bring two long space journeys. The last advantage we'll
talk about is that it could help keep astronauts sane
on their way to Mars.
Speaker 3 (25:35):
So it takes about two years to go back and forth,
which means you are isolated and confined for this period
of time together with your colleagues in a small habitat.
So they are adding a lot of psychological factors to it.
There's even a syndrome called the Earth out of side syndromes.
When it's just anticipating, you see the Earth going p sized.
When you are landing on Mars. You can just see it,
(25:57):
but it's very far away and you may imagine and
not long it will take to be rescued or there's
an issue. So there are a lot of factors which
are added. And this is too interesting because there are
different levels to add on top and on top, and
the question is always how much can we overcome, how well,
can we deal with these sum up stressors and how
is the body able to compensate. You may compensate for
(26:18):
the one, you may comment for the other, but some
effects and no one really knows because no one has
ever experienced such a long voyage.
Speaker 1 (26:26):
What Doctor should Care is saying is that going to
space is stressful. You're always in mortal danger, far far
away from any help, and on top of that, you're
stuck in a small space with other people and there
could be drama if tensions get high. So being able
to hibernate for most of that journey to Mars could
(26:47):
really help everyone stay sane. Okay, and now we come
to the big question, which is can we make hibernation
work in humans? Well, according to doctor Kelly Drew, there
are people I think this idea using drugs. So then
what's the prospect of doing this in humans? What do
we know about whether we can induce it as it worked?
Speaker 2 (27:10):
Well, there is a lab that is funded by NASA
at the University of Pittsburgh and run by clinician named
Cliff Collaway, and they are working in people. They're using
currently known drugs anesthetics that are good at turning down
the thermostat. He's using an anesthetic called dex metatomidine, and
(27:32):
he sees that it is the best of all the
drugs used for cooling to suppress shivering. And they're measuring
how much metabolic savings they can achieve and how comfortable
people are when they're cold, and they're showing energy savings
and it's not profound, but you know, we're also working
(27:52):
on drugs that target the dentistin system.
Speaker 1 (27:57):
So a dentistine is a super important molecule that's used
all over your body. It's involved in how we process energy.
It's part of RNA and DNA, and it's a transmitter
molecule in your brain. If you drink coffee or tea,
caffeine wakes you up by blocking a dentisine in your neurons.
And it also seems to be a part of hibernation.
(28:19):
You can use it to trigger hibernation in animals or
by blocking it you can delay an animal from hibernating.
What doctor Dury is saying is that scientists are working
on drugs that affect this adenosine molecule.
Speaker 2 (28:34):
And part of what we see is a little scary
from a clinical perspective because there's very low blood flow,
very low heart rate, but we are beginning to think
that that is part of the metabolic suppression.
Speaker 1 (28:46):
What do you mean, it's scary because it is so
close to death.
Speaker 2 (28:49):
It is so close to death, it really is. Yeah,
So it has to be very well understood and very
well monitored and you know known, because you know, we
don't have all the adaptations that these ground squirrels have.
We haven't already been optimized to tolerate the challenges of hibernation,
and so we have to be very careful and understand
(29:09):
it and know how to manage it so that it's
you know, it's not risky.
Speaker 1 (29:14):
So we have been experimenting with making this work in
humans and there are signs that it could work. But
the hard part is that we're still not sure how
the whole body process of hibernation should get started, because
in a way, it has to start from inside the body.
Speaker 3 (29:32):
So hibernation it comes from your body. It's not external. Okay,
it starts indulgeously. And this is what animals are doing.
They have no drugs, nothing, They're just there and this
is their mechanisms in start that we don't understand yet
whether they start on the brain, whether they start on
the cellar level, this is still open and under debate.
Transferring this to the humans, I mean today we have
(29:56):
no real real evidence that human is a hibernator, not
at all. But we have also no evidence that who
human cannot be a hibernator. So the mechanisms might be
still inherited in us. However, how this may work is
completely open.
Speaker 1 (30:13):
Now what's interesting is that there are examples of humans
that can sort of go into hibernation. They're called yogis.
Speaker 2 (30:23):
You know, the best examples are yogi's. Really well practiced
yogis can do this. I mean they can lower metabolism,
lower blood pressure. They do that mostly through their breath
and involves a parasympathetic nervous system. And that is something
also that we see in hibernation is they definitely use
their parasympathetic nervous system as they enter hibernation. So that's
(30:46):
another nice human example of what's possible.
Speaker 1 (30:49):
I mean, yogis, this is real.
Speaker 2 (30:51):
This is not oh, this is real. This is these
are you know, life practicing yogis that can lower body
temperature and metabolism, heart rate dramatically, not eat for days.
I don't know what the record is. It's not in
the literature as much as it's you know, just stories,
but there's certainly some extreme ability. Also, you know, people
(31:15):
who dive really you know, prolonged diving, breathholding can develop
some of these skills.
Speaker 1 (31:22):
Wow, it's under our control.
Speaker 2 (31:24):
Kind of that is under our control with training.
Speaker 1 (31:26):
Oh wow, fascinating. So that's where we are today. Can
we hibernate humans? We're sort of at the point where
we have a lot of knowledge about hibernation in some
species of animals and we have to dream of making
it work in humans for things like space travel. Now
it's just a matter of closing that gap. We need
to understand more how hibernation is triggered in animals, and
(31:50):
we need to start testing out whether those strategies can
work in people and whether our bodies can survive being
at lower temperatures. As doctor Drew says, it's no matter
of funding the size of it to learn more.
Speaker 2 (32:04):
It's really ripe for discovery, and yet it's also kind
of thinking outside the box and hard to get resources
to do to study. So I appreciate your program. I
appreciate being able to share some of the possibilities and
I hope people are interested and will support it.
Speaker 1 (32:21):
Yeah. Yeah, Like I said, I'm ready to invest.
Speaker 3 (32:24):
This idea.
Speaker 1 (32:25):
All right, we will have to talk, all right. We
hope you enjoyed that. Thanks for joining us. I'm going
to go take a nap now, but don't worry. I
plan to wake up before next week's episode. See you. Then,
you've been listening to Science Stuff production of iHeartRadio, written
(32:48):
and produced by me or hitch Ham candidate by Rose Seguda,
executive producer Jerry Rowland, an audio engineer and mixer Kasey Peckram,
and you can follow me on social media. Just search
for PhD Comics and the name of your favorite platform.
Be sure to subscribe to Sign Stuff on the iHeartRadio app,
Apple Podcasts, or wherever you get your podcasts, and please
(33:08):
tell your friends we'll be back next Wednesday with another episode.
Hey, please take a second and leave us a review
on Apple Podcasts, Spotify, or wherever you listen to the podcast.
Thanks a lot. Hey, welcome to Science Stuff, a production
of iHeartRadio. I'm hort Jam and today we're answering the
question can we hibernate humans? We know bears can do it,
some birds can do it, and even lemurs can do it.
(00:23):
But could we get a person to hibernate? And would
it lead to breakthroughs in emergency medicine, cancer research, and
even space travel. We're gonna talk to a biologist who's
been studying hibernation in animals for thirty years, as well
as a medical researcher who's been working with the European
Space Agency to see if this would let humans travel
(00:44):
to distant stars. So get nice and cozy and get
ready to enter a state of science torpor as we
answer the question can we hibernate humans? Hey? Everyone do?
They were asking three questions, what is hibernation, can we
(01:06):
get it to work in people? And why would we
want to hibernate a person? It turns out there are
a lot of reasons why we would want to do that,
including maybe letting us explore the cosmos, but first we
need to understand what it is and how animals are
able to do it. So my first conversation was with
Professor Kelly Drew.
Speaker 2 (01:29):
So, my name's Kelly Drew. I am a professor at
the University of Alaska, Fairbanks, and I direct a NIH
funded center called the Transformative Research and Metabolism. So I've
studied hibernation for about thirty years, so I'm very much
focused on the brain and hibernation.
Speaker 1 (01:46):
Incredible. I think you're the perfect person for us to
talk to you today.
Speaker 2 (01:49):
Awesome.
Speaker 1 (01:50):
Maybe start us off, how do you define hibernation? What
is it?
Speaker 2 (01:53):
Well, the big picture of hibernation is that it's a
metabolic adaptation where it suppresses metabolism and body temperature because
sometimes they need to conserve that energy if food is
not available, and many animals do it. Everything from some primates.
There's the fat tailed lemur from Madagascar. There's marmots. Bears hibernate,
(02:15):
not polar bears. Polar bears don't hibernate because they have
food year round because they fish off the ice, but
black bears and grizzly bears hibernate. And then there's ground
squirrels and hamsters, even the common house mouse. If you
take its food away, it will hibernate. Hummingbirds will hibernate.
Speaker 1 (02:35):
Hummingbirds.
Speaker 2 (02:36):
Yeah, there's a lot of different species.
Speaker 1 (02:40):
Yes, hummingbirds hibernate too. Okay. The big question I had
for doctor Drew was how is hibernation different from sleep?
Speaker 2 (02:49):
Actually is thought to be an extension of sleep, So
at least with hibernation, animals have to sleep to enter hibernation.
And what I think is that there's a process that
kind of flips a switch that allows the temperature to
continue to cool, and then cold by itself plays a
role in suppressing metabolism.
Speaker 1 (03:10):
So hibernation is not just sleep. Something else kicks in
in animals during hibernation, and that causes two things to happen.
One through metabolism, meaning how active the cells in their
body are slows down. And two, their body temperature drops.
And this is a key feature of hibernation because normally
(03:31):
your body doesn't let your body temperature go down. Even
when you sleep, your body doesn't drop below one or
two degrees of its normal temperature. It's all part of
our survival mechanism.
Speaker 2 (03:44):
We all have a point where if we get to
a certain temperature, our bodies kick in the keaters, humans
will shiver, we start generating heat. And so the trick
is that during hibernation, your body allows it to get
a little bit colder than what we normally do. So
it's often thought of as well, you just lower the thermostat,
reset the set point on the thermostat, and you get
(04:06):
down to a colder temperature, and that temperature helps to
suppress metabolism. So you go into this kind of state
of nirvana, very low energy consumption, and everything just sort
of quiets down.
Speaker 1 (04:18):
I see. So once we go into tibernation, our set
point is set lower, and so the body gets colder
and that doesn't do any harm to the organism.
Speaker 2 (04:27):
Well, the ground squirrel is especially adapted to cold tissue temperature.
For humans, if our bodies go below about thirty degrees celsius,
then we can have cardiac arrhythmias, so the heart doesn't
function all that well. But the ground squirrels are specially
adapted and their body temperature goes down actually to minus
three degrees below freezing, wow, minus three celsius, and they
(04:49):
have no trouble with that.
Speaker 1 (04:53):
So Hibernation isn't just about slowing your heart rate or
going to sleep for a long time. Something really fundamental
happens to animals that hibernate. Their entire bodies recalibrate to
work at a lower temperature, which is something that normally
our bodies very strongly rejects. I mean, if you go
below thirty degrees celsius or eighty six degrees fahrenheit, as
(05:16):
doctor Drew said, your heart basically stops working. But animals
that hibern need have a special mechanism that lets them
run super cold.
Speaker 2 (05:26):
And so the ground squirrels have adapted these temperature mechanisms
so they keep things functioning even in the cold. I
mean the same thing in your car. You know, you
change the weight of your oil for winter compared to summer,
so you want a little bit less viscous oil in
the winter.
Speaker 1 (05:41):
I see, I live in California and I'm from Panama,
so this is need to me, that's the in fact
that you need to change your oil. But in Alaska,
I imagine that's a common thing.
Speaker 2 (05:51):
Very common. Yes, So all those kinds of things. Animals
have adaptations that allow them to tolerate different temperatures, and
we don't know really what all those are.
Speaker 1 (06:03):
Okay, here I had a lot of questions for doctor Drew,
like what's happening in the brain of these animals when
they hibernate, Do they dream or are they conscious? What
triggers this hibernation mechanism? And then what's going on in
the brain while animals are in the state.
Speaker 2 (06:20):
Well, like I said, they are first sleeping, but as
they cool, the magnitude of the brain waves they shrink
and get lower and lower as the animal cools, until
finally it becomes flat. And that actually looks somewhat like
being in a coma, but they're not in a coma
because they can be induced to arouse just by handling.
Speaker 1 (06:42):
But it's more extreme than sleeping for example.
Speaker 2 (06:44):
Right, Yeah, it's a different state of consciousness. So cold
really continues to dampen the brain waves so that then
they will become flat.
Speaker 1 (06:54):
Meaning like the brain doesn't work at those lower temperatures.
Speaker 2 (06:57):
You don't see any electrical activity.
Speaker 1 (06:59):
That means, so basically the brain of the animal stops working.
It's almost being brain dead, but not quite. In fact,
it's something very different. Amazingly hibernating animals have been shown
to be able to learn while they hibernate.
Speaker 2 (07:18):
And they can learn actually when they're in this state.
Speaker 1 (07:22):
Wow, what do you mean they learn? How can they
learn if they're passed out?
Speaker 2 (07:25):
What they learn is they habituate to handling. If you're
like needing to do something with the animal when they're
in hibernation, you can just handle them, and at first
they'll be bothered by it, and they'll start to wake up.
And if you do that over and over, they pretty
much get used to it to where they just don't
bother anymore. They're used to it. If you go in
and handle them, they won't arouse. Wow, And so we
(07:48):
consider that to be learning. It's called habituation.
Speaker 1 (07:50):
Oh wow, that's uds like my teenage son when you're
trying to.
Speaker 2 (07:56):
That's exactly it.
Speaker 1 (07:59):
Yeah, even though their brain activity is totally flat and
they seem like they're in a coma or brain dead,
the hibernating animal can still somehow process what is happening
to it. It's really a very different state of being. Okay.
The next question I had was what triggers hibernation.
Speaker 2 (08:18):
We've got animals that hibernate according to season. We call
them obligate hibernators. So they have a clock in their
bodies that tell them what time of year it is,
and no matter whether it's cold or dark, or whether
they have food or don't have food, they will hibernate.
And those are the ground squirrels and other species like
the hamsters are what are called facultative hibernators, and for those,
(08:42):
the hibernation has to be induced by short days, so
like what you would see in winter. Other animals like
mice will hibernate just because they don't have food. It's
just simply, hey, we don't have any food. Let's chill
for a while as long as we can, and then
we're gonna warm up again. See if there's any food.
Speaker 1 (09:01):
Oh, I see, let's just wait it out and see
what happens. Yeah, what about like bears.
Speaker 2 (09:05):
And bears are a little bit more facultative because if
it's warm, they won't hibernate. If they have a whole
lot of food, they don't hibernate. So bears, because they're
so big, they don't actually get that cold. They don't
get colder than about thirty degrees see, but they suppress
their metabolism down to twenty five percent of basil metabolic rate.
(09:26):
So basil metabolic rate is as low as you can go.
Speaker 1 (09:30):
If you go lower, you're dead.
Speaker 2 (09:31):
Kind of, yeah, you're dead.
Speaker 1 (09:33):
Would you say? That's kind of a definition of hibernation
is let you basically slow your body down to where
you would normally be.
Speaker 2 (09:40):
Dead, exactly right. And lots of people like to think
of it as near death, and that way is very similar,
and we like to imagine that hibernation is a state
that kind of is near death, but it can be reversed.
Speaker 1 (09:57):
All right, When we come back, we're going to talk
about another interesting fact site to sit found about hibernation,
and then we're going to talk about whether we could
ever make it happen in humans. Don't go anywhere, we'll
be right back. Hey, welcome back. We're talking about hibernation
(10:28):
and whether we could ever do it in humans. And
so far we've learned what hibernation is, which animals do it,
what triggers it, and whether animals dream while they hibernate.
The last thing we're going to talk about before we
get to hibernation humans is that hibernation in animals is
not constant. There's a cycle in hibernation.
Speaker 2 (10:50):
And for whatever reason we don't understand animals when they
go colder than thirty degree c they have to rewarm
every so often. Hamsters will rewarm every three to four
five days. Ground squirrels rewarm every two to three weeks,
and we call these interbout arousals. And during that interbout arousal,
they sleep, so the flat eeg turns into slow wave sleep.
(11:11):
They make glucose, they urinate just a little bit, they
fluff up their nest, and they sleep and then they
re enter torpurth.
Speaker 1 (11:20):
Torpor, by the way, is what scientists call that deep
low metabolism, cold temperature, almost brain dead state animals enter
during hibernation. But what doctor Drew is saying is that
animals are not in that state the whole time. They
kind of stir and kickstart their body every so often
throughout the hibernation period, and scientists think animals do this
(11:42):
to kind of do body maintenance.
Speaker 2 (11:46):
Something initiates that in about arousal. That evidence suggests that
it's either an accumulation of something a waste that they
have to get rid of, or a lack of metabolite
that they need, like for example, glucose and so they
need to make glucose and they can't do it when
they're cold. So during hibernation, they may need to warm
(12:06):
up to make glucose. They may need to warm up
to get rid of nitrogen somehow, And so that's what
we think is that they have to warm up periodically
to do some of that metabolic work.
Speaker 1 (12:18):
So you're saying built into hibernation is this sort of
periodic arousal where they do a little bit of maintenance
and then they go back to hibernation.
Speaker 2 (12:27):
That's right, that's right.
Speaker 1 (12:29):
All right, And now we get to the topic of
making humans hibernate. And the first question you might have
is why hibernate a human? Well, according to doctor Drew,
there are many reasons why we would want to put
humans in a deep state of torpor. Okay, why would
we want to hibernate humans?
Speaker 2 (12:47):
Well, the most lowest hanging fruit is for critical care,
particularly for brain injury. Like if you have a cardiac
arrest that means like sudden heart failure, you fall on
the ground and now you're comatose and you get resuscitated
by CPR. Those people actually wouldn't know it, but they
ultimately die from brain injury. So even though they can
bring them back, the brain doesn't tolerate that lack of
(13:10):
blood flow very well. So if we can induce hibernation,
there's potential that it could have immediate benefit to people
that suffer stroke or cardiac or risk drowning or lack
of oxygen.
Speaker 1 (13:22):
How would that help them, Well, it may.
Speaker 2 (13:24):
Just simply prevent the injury caused by the lack of
blood flow, or it could stabilize the injury while every
other processes kind of come back to normal and then
allows the body to kind of deal with it at
a slower pace at a better time.
Speaker 1 (13:39):
Meaning you just want to slow everything down so that
the injuries don't get worse.
Speaker 2 (13:43):
Yes, right, having them enter this hibernation natural cooling state
is expected to be more beneficial.
Speaker 1 (13:50):
I see. So that's one reason we might want to
hibernate a person in an emergency. Going into hibernation could
cool the body down going into hypothermia, and that would
slow the response to the body so that doctors have
more time to deal with the injury. And this could
be useful not just in heart attacks and strokes, but
(14:11):
in any kind of injury where medical care is not
easy to get.
Speaker 2 (14:16):
So you could stabilize somebody by putting them into a
hibernation state, and how you can get them to medical facilities.
It certainly battlefield operations. Same with remote emergency care. If
somebody falls mountain climbing or whatever and is injured but
they can't be evacuated for a period of time, they
could be stabilized by putting them into these states.
Speaker 1 (14:38):
And another interesting reason to hibernate people is to maybe
save the planet, he said, saving the planet. What's the
scenario there?
Speaker 2 (14:47):
So the other kind of grandiose ideas I've heard. One was, well,
we can save the planet if you know, we can
just all chill on a regular basis. We don't drive
as much, we don't use as much electricity, all these things.
Speaker 1 (15:01):
Like we would all go into hibernation every once in
a while or every night or what do you mean?
Speaker 2 (15:05):
Yeah, maybe for you know, like life holidays, Yeah, a
couple of weeks at a time. I think it was
inspired by COVID a little bit, because as horrible as
it was, we definitely saved some things. You know, traffic
was less and pollution lowered, wasn't so bad. People get
(15:25):
pretty engaged in the life and hard to say, well,
I'm just going to cut out for a couple of
weeks or a month.
Speaker 1 (15:32):
Yes, we could take hibernation vacations. Say you just want
to check out for a few days or a few months,
you could hibernate, and overall we would reduce human activity,
which could be good for the planet. I mean, how
many of us would like to take a break right
now and not wake up until the next presidential election.
And doctor Drew says taking hibernation vacations wouldn't just reduce
(15:54):
your carbon footprint, it could actually help you dage and
live longer.
Speaker 2 (16:02):
But what's interesting and hybridating animals is they do live longer.
Hibernation prolongs life, but you just kind of a pause.
It's not the wear and tear on the body. You're
really taking a break and cooling and rewarming. There's evidence
that it has some regenerative properties, so you can actually
you know, regenerate synapses, potentially regenerate muscle. But certainly in
(16:24):
hibernation is interesting because even though they don't eat or
move for eight months, they wake up strong. Whoa, they
don't lose any muscle.
Speaker 1 (16:33):
So they live longer, not just because they pause their body.
But because there's other benefits to hibernation.
Speaker 2 (16:40):
There could be that's still a hypothesis, but we're seeing
evidence of cold and rewarming. The combination of cooling and
rewarming stimulates regenerative processes.
Speaker 1 (16:50):
I see. You would think that it's just your body
kind of goes downhill when you're hybrided. But now there's
something stimulating about hibernation. Yeah, fascinating.
Speaker 2 (16:59):
But you know it's also a wonderful weight loss program.
Speaker 1 (17:03):
What do you mean, what do you mean.
Speaker 2 (17:04):
Well, you don't eat, metabolism is down These ground squirrels
can double their body weight pre hibernation and then they
lose all of that by spring, but they're fit and
trim when they wake up.
Speaker 1 (17:16):
Oh wow, that does sound like a really good program.
Well I am all in on that startup. Right, that's
Fitness Life Extension. Where do I sign a check for
that investment?
Speaker 2 (17:31):
Exactly?
Speaker 1 (17:33):
That's right. You could use hibernation to lose weight during
hibernation and the most burnt fat to stay alive. And
so you could imagine going into hibernation for a while
and waking up thinner without having to diet or exercise. Okay,
the last super interesting reason to hibernate people is for
space travel. You've all seen the science fiction movies where
(17:55):
astronauts climb to a sleeppond and going to suspended animation.
But why is that? How does hibernation help with goin
as space? To find out, I talked to a medical
researcher that's been working with the European Space Agency on
this idea. Well, thank you, doctor Huk for joining us.
Speaker 3 (18:13):
It's my pleasure. I'm very curious a lot your questions
and to explore with you together, you know, the new
perspectives of potential hibernating humans.
Speaker 1 (18:21):
One day, can you please tell us who you are
and what you do.
Speaker 3 (18:24):
I'm a physician by training during research and mostly about
organ protection, which has brought me to this field of
spaceflight and how the organisms reacting to extreme environments.
Speaker 1 (18:35):
Okay, now, according to doctor Chuk, there are several reasons
why being able to hibernate would help humans travel through space. Now,
you probably think the main reason is the one you
see in movies, which is that space is huge and
it takes a long time to get anywhere. For example,
the near start to us Proximus centory is forty trillion
(18:57):
miles away and getting there could take hundreds or even
thousands of years. So being able to climb to a
pod and somehow good sleep and stop aging means you
could actually survive the trip. This is true. But actually
NASA and the European Space Agency are interested in hibernation
for more practical reasons, and they're looking at it as
(19:19):
a strategy for shorter journeys like say to Mars. Getting
to Mars takes a little less than a year. So
why would we need to hibernate? Well, like I said,
there are several reasons, and the first is that when
you're hibernating you don't need to eat as much. You said,
there are big advantages in terms of resources. Can you
(19:40):
explain what that means?
Speaker 3 (19:41):
Yeah, we did a study with the European Space Agency.
We designed the mission of six people going to Mars
and back just theoretical design. What do would that mean?
How much resources do we need? How much oxygen, how
much water supply, food supply, so on. What would be
the scenarios of being under hibernation condition versus another high
condish And of course oxygen you save a lot, but
(20:03):
the most tracking element is for food. For instance, you
have maybe a twenty percent of fifteen percent of food needed.
Speaker 1 (20:10):
Only Doctors huqu In the European Space Agency calculated that
for a six percent mission to Mars, where everyone stays
awake the whole time, you need to bring about six
tons of food, which is six thousand kilograms or about
thirteen thousand pounds of food. And that's because the whole
trip would take about two years, and so you need
(20:32):
over two thousand, two hundred meals for six adults, and
there are no grocery stores along the way, so you
have to bring everything. But then they compared that to
a Mars mission in which the crew hibernated some or
all of the way there and back, and the amount
of food you need in that case turns out to
be only seven hundred kilograms, or about fifteen percent of
(20:54):
the original amount. That's about five tons of payloads that
you don't need to bring. If you hibernate the crew,
you only need sixty seven hundred kilograms.
Speaker 3 (21:05):
Wow, exactly. This makes the difference. And when you just
think about the implementation of a travel to Mars, you
just need less payloads. Yeah, so this is why agencies
maybe like it. Yeah, yes, we reduce the payloads. You
need less stuff to get uploaded, and every kilochrome every
pound costs a lot of money.
Speaker 1 (21:24):
So hibernation would make space travel cheaper. Another reason hibernation
would help going to space is that hibernation apparently makes
you more immune to radiation damage. Space is full of
harmful radiation, some of which comes from the Sun and
some of which comes from cosmic rays, but it's a
(21:45):
real problem for astronauts. It means that your chances of
getting cancer out in space are much higher than if
you stay on Earth. But for reasons that scientists aren't
quite sure of, going into hibernation makes you more radiation.
Speaker 3 (22:03):
When you relief of vicinity and go the younger fun
old belt and having less protection, you will see more
radiation effects there it will increase, and depending on solar eruptions,
this may even be detrimental. So radiation resistance is a
big thing.
Speaker 1 (22:19):
Doctor Chuke says that scientists in Germany and Italy have
done experiments where they induce torpor in test animals and
they found that it kind of protects them from radiation damage.
And the reason for that is not quite clear to scientists.
Some think it's because your cells are not multiplying as much,
so there's few chances for the radiation to cause inmutation.
(22:41):
But it could also be because during hibernation, the body
is better at repairing itself. And this brings up another
reason hibernation could help in space travel, and that is
what we mentioned before in animals. When animals hibernate, they
don't lose bone or muscle mass. Hibernating animals wake up
trim and fit and ready to go. But human bodies
(23:03):
when they're in space start to go downhill and deteriorate fast.
Speaker 3 (23:10):
When you stay lower in space, the problems may really
kick off. It might be either the conditioning of the
body so you're not experiencing gravity, pull on your bone,
on your muscle, so you get rid of some volume
that you don't need. The bones are gone muscles. Yeah,
there was a research paper summarizes you need a new
skeleton in the closet when you leave this even when
you survive. But because your bones get really weak because
(23:33):
of this deconditioning effect that you don't challenge your body.
And if you had the chance to put someone in hibernation,
these degenerated processes would stop, yeah, or would be wow,
maturely reduced.
Speaker 1 (23:46):
I hadn't thought about that. So we've seen that in animals.
Animals don't lose bone or muscle.
Speaker 3 (23:52):
Exactly, they don't lose bone and muscle and wake up
and up back to the business.
Speaker 1 (23:56):
So to say, clearly, being able to hibernate humans would
be a game changer for space travel. You could imagine
hopping on a spaceship going into hibernation, and when you
wake up, you're in Mars, and not only are you
well rested and less damaged by radiation, but you feel great,
maybe even in better shape than when you went to sleep.
(24:19):
So now the question is can we actually do it
in humans? Is it actually possible to hibernate people? When
we come back, we'll ask our two experts this question.
We'll find out what scientists have done to make this happen.
Don't go anywhere, we'll be right back, and we're back.
(24:53):
We're talking about the possibility of hibernating humans, and so
far we've talked about how hibernation worksimals and what are
some of the reasons we would want to make it
happen in people. It could help with emergency medicine, producing
our carbon footprint and may even have health benefits. It
could also be a game changer for space travel. We
(25:14):
heard from doctor Alexander Chuquet, a physician that works with
the European Space Agency, on what space does to the
human body, and he listed some of the advantages hibernation
could bring two long space journeys. The last advantage we'll
talk about is that it could help keep astronauts sane
on their way to Mars.
Speaker 3 (25:35):
So it takes about two years to go back and forth,
which means you are isolated and confined for this period
of time together with your colleagues in a small habitat.
So they are adding a lot of psychological factors to it.
There's even a syndrome called the Earth out of side syndromes.
When it's just anticipating, you see the Earth going p sized.
When you are landing on Mars. You can just see it,
(25:57):
but it's very far away and you may imagine and
not long it will take to be rescued or there's
an issue. So there are a lot of factors which
are added. And this is too interesting because there are
different levels to add on top and on top, and
the question is always how much can we overcome, how well,
can we deal with these sum up stressors and how
is the body able to compensate. You may compensate for
(26:18):
the one, you may comment for the other, but some
effects and no one really knows because no one has
ever experienced such a long voyage.
Speaker 1 (26:26):
What Doctor should Care is saying is that going to
space is stressful. You're always in mortal danger, far far
away from any help, and on top of that, you're
stuck in a small space with other people and there
could be drama if tensions get high. So being able
to hibernate for most of that journey to Mars could
(26:47):
really help everyone stay sane. Okay, and now we come
to the big question, which is can we make hibernation
work in humans? Well, according to doctor Kelly Drew, there
are people I think this idea using drugs. So then
what's the prospect of doing this in humans? What do
we know about whether we can induce it as it worked?
Speaker 2 (27:10):
Well, there is a lab that is funded by NASA
at the University of Pittsburgh and run by clinician named
Cliff Collaway, and they are working in people. They're using
currently known drugs anesthetics that are good at turning down
the thermostat. He's using an anesthetic called dex metatomidine, and
(27:32):
he sees that it is the best of all the
drugs used for cooling to suppress shivering. And they're measuring
how much metabolic savings they can achieve and how comfortable
people are when they're cold, and they're showing energy savings
and it's not profound, but you know, we're also working
(27:52):
on drugs that target the dentistin system.
Speaker 1 (27:57):
So a dentistine is a super important molecule that's used
all over your body. It's involved in how we process energy.
It's part of RNA and DNA, and it's a transmitter
molecule in your brain. If you drink coffee or tea,
caffeine wakes you up by blocking a dentisine in your neurons.
And it also seems to be a part of hibernation.
(28:19):
You can use it to trigger hibernation in animals or
by blocking it you can delay an animal from hibernating.
What doctor Dury is saying is that scientists are working
on drugs that affect this adenosine molecule.
Speaker 2 (28:34):
And part of what we see is a little scary
from a clinical perspective because there's very low blood flow,
very low heart rate, but we are beginning to think
that that is part of the metabolic suppression.
Speaker 1 (28:46):
What do you mean, it's scary because it is so
close to death.
Speaker 2 (28:49):
It is so close to death, it really is. Yeah,
So it has to be very well understood and very
well monitored and you know known, because you know, we
don't have all the adaptations that these ground squirrels have.
We haven't already been optimized to tolerate the challenges of hibernation,
and so we have to be very careful and understand
(29:09):
it and know how to manage it so that it's
you know, it's not risky.
Speaker 1 (29:14):
So we have been experimenting with making this work in
humans and there are signs that it could work. But
the hard part is that we're still not sure how
the whole body process of hibernation should get started, because
in a way, it has to start from inside the body.
Speaker 3 (29:32):
So hibernation it comes from your body. It's not external. Okay,
it starts indulgeously. And this is what animals are doing.
They have no drugs, nothing, They're just there and this
is their mechanisms in start that we don't understand yet
whether they start on the brain, whether they start on
the cellar level, this is still open and under debate.
Transferring this to the humans, I mean today we have
(29:56):
no real real evidence that human is a hibernator, not
at all. But we have also no evidence that who
human cannot be a hibernator. So the mechanisms might be
still inherited in us. However, how this may work is
completely open.
Speaker 1 (30:13):
Now what's interesting is that there are examples of humans
that can sort of go into hibernation. They're called yogis.
Speaker 2 (30:23):
You know, the best examples are yogi's. Really well practiced
yogis can do this. I mean they can lower metabolism,
lower blood pressure. They do that mostly through their breath
and involves a parasympathetic nervous system. And that is something
also that we see in hibernation is they definitely use
their parasympathetic nervous system as they enter hibernation. So that's
(30:46):
another nice human example of what's possible.
Speaker 1 (30:49):
I mean, yogis, this is real.
Speaker 2 (30:51):
This is not oh, this is real. This is these
are you know, life practicing yogis that can lower body
temperature and metabolism, heart rate dramatically, not eat for days.
I don't know what the record is. It's not in
the literature as much as it's you know, just stories,
but there's certainly some extreme ability. Also, you know, people
(31:15):
who dive really you know, prolonged diving, breathholding can develop
some of these skills.
Speaker 1 (31:22):
Wow, it's under our control.
Speaker 2 (31:24):
Kind of that is under our control with training.
Speaker 1 (31:26):
Oh wow, fascinating. So that's where we are today. Can
we hibernate humans? We're sort of at the point where
we have a lot of knowledge about hibernation in some
species of animals and we have to dream of making
it work in humans for things like space travel. Now
it's just a matter of closing that gap. We need
to understand more how hibernation is triggered in animals, and
(31:50):
we need to start testing out whether those strategies can
work in people and whether our bodies can survive being
at lower temperatures. As doctor Drew says, it's no matter
of funding the size of it to learn more.
Speaker 2 (32:04):
It's really ripe for discovery, and yet it's also kind
of thinking outside the box and hard to get resources
to do to study. So I appreciate your program. I
appreciate being able to share some of the possibilities and
I hope people are interested and will support it.
Speaker 1 (32:21):
Yeah. Yeah, Like I said, I'm ready to invest.
Speaker 3 (32:24):
This idea.
Speaker 1 (32:25):
All right, we will have to talk, all right. We
hope you enjoyed that. Thanks for joining us. I'm going
to go take a nap now, but don't worry. I
plan to wake up before next week's episode. See you. Then,
you've been listening to Science Stuff production of iHeartRadio, written
(32:48):
and produced by me or hitch Ham candidate by Rose Seguda,
executive producer Jerry Rowland, an audio engineer and mixer Kasey Peckram,
and you can follow me on social media. Just search
for PhD Comics and the name of your favorite platform.
Be sure to subscribe to Sign Stuff on the iHeartRadio app,
Apple Podcasts, or wherever you get your podcasts, and please
(33:08):
tell your friends we'll be back next Wednesday with another episode.
Popular Podcasts
Las Culturistas with Matt Rogers and Bowen Yang
Ding dong! Join your culture consultants, Matt Rogers and Bowen Yang, on an unforgettable journey into the beating heart of CULTURE. Alongside sizzling special guests, they GET INTO the hottest pop-culture moments of the day and the formative cultural experiences that turned them into Culturistas. Produced by the Big Money Players Network and iHeartRadio.
The Joe Rogan Experience
The official podcast of comedian Joe Rogan.
Stuff You Should Know
If you've ever wanted to know about champagne, satanism, the Stonewall Uprising, chaos theory, LSD, El Nino, true crime and Rosa Parks, then look no further. Josh and Chuck have you covered.