Something You Should Know - Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
Episode Date: April 24, 2025You are familiar with the advice that you shouldn’t go grocery shopping when you are hungry because you will spend more money and buy more junk. However, that’s just a piece of story. Hunger and ...shopping are related in other ways. This episode begins by explaining how. https://phys.org/news/2015-03-hungry-people-food.html#google_vignette The idea that spending too much time on your phone, tablet or computer is bad for you has become conventional wisdom. But is that true? What does the research say about this? It turns out it's not black and white, there are shades of gray worth understanding. Here to explain this is Jacqueline Nesi. She is a psychologist and assistant professor at Brown University who writes the popular weekly newsletter Techno Sapiens (https://technosapiens.substack.com), which provides tips to manage your screen time better. She has published over 50 peer-reviewed publications related to technology use and has appeared on CNBC, CNN, and NPR. Your body is an amazing collection of processes and systems that all work to keep you alive and moving. Most of us have no idea what goes on inside of us to make it all happen so, here to explain some of it and unravel a few mysteries of the human body and explain why we can’t live forever, how the body defends itself, why we need to sleep and so much and more is Dr. Darragh Ennis. He is a scientist and researcher who has worked at the University of Oxford and the University of Glasgow and he is author of the book The Body: 10 Things You Should Know (https://amzn.to/42ApkC5). Have you heard the word “halfalogue? It’s when you hear someone else talking on their phone but you are hearing only their side of the conversation. It can drive you crazy and it has other implications, especially if you are driving a car. Listen as I explain. https://news.cornell.edu/stories/2010/05/half-heard-phone-conversations-reduce-performance PLEASE SUPPORT OUR SPONSORS!!! FACTOR: Eat smart with Factor! Get 50% off at https://FactorMeals.com/something50off TIMELINE: Get 10% off your order of Mitopure!  Go to https://Timeline.com/SOMETHING INDEED: Get a $75 sponsored job credit to get your jobs more visibility at https://Indeed.com/SOMETHING right now! SHOPIFY:  Nobody does selling better than Shopify! Sign up for a $1 per-month trial period at https://Shopify.com/sysk and upgrade your selling today! Learn more about your ad choices. Visit megaphone.fm/adchoices
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Today on Something You Should Know, how hunger affects what you buy.
Not just groceries, everything you buy.
Then some facts and
myths about screen time and video games. You know there was a big concern for a
while about violence in video games. Generally the research does not support
any long-term links between playing violent video games and violent or
aggressive outcomes in the long term. Also, why listening to other people talk on their phones
can drive you nuts,
and the amazing ways your body works,
your heart, your immune system, your brain.
Your brain washes itself at night time.
There's been studies where they've watched people
when they're going to sleep,
and they've seen pulses of cerebrospinal fluid
going over the brain during sleep.
And they really think that this maintenance time of sleep
helps remove bad things for your brain, toxin buildup.
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Something you should know.
Fascinating intel.
The world's top experts and practical advice you can use in your life.
Today, something you should know with Mike Carruthers.
I think everybody knows that it's a bad idea
to go grocery shopping when you're hungry
because you're going to spend more money and buy more junk.
But there's more to the story.
Hi, and welcome to this episode of Something You Should Know.
Not only does research support the fact
that grocery shopping when you're hungry
will cause you to spend more money,
you probably have personal experience in that regard.
But it turns out that shopping for anything
on an empty stomach is a bad idea.
Researchers at the University of Minnesota
found that hungry people spent 64% more money at the mall on
anything than shoppers who were not hungry.
Apparently, hunger kicks in that human desire to hunt and gather, and since few of us are
hunting and gathering in the traditional sense, we go shopping instead.
Also, be aware of the scent of cinnamon. It seems that that makes
you want to spend more money. And if you're a woman, a University of Texas study found
that women want to buy more stuff when they're ovulating. So that's another time to avoid
going shopping. And that is something you should know.
A very big concern today is screen time. How much time you or your kids have a computer or a tablet or a phone screen in front of your face.
And the assumption is that you're probably spending too much time looking at screens.
And what you really need to do is cut back
and spend less time with screens.
But what is too much time?
What's the actual harm?
Does screen time affect everyone the same way?
What does the research say about how screen time impacts people?
The answers to those questions just may surprise you.
And here to reveal all this is Jacqueline Neese.
She is a psychologist and assistant professor at Brown University,
and she writes a popular weekly newsletter called
TechnoSapiens, which provides tips to manage your screen time.
Jackie has published over 50 peer-reviewed publications related to technology use.
She's testified before
U.S. Congressional and state legislative committees on issues surrounding technology and mental
health.
Hey, Jackie, welcome to Something You Should Know.
Hey, thank you so much for having me.
So you hear all the time, people talk about all the time about how we shouldn't be on
screen so much, that, you know, get off your phone,
you're on your screens too much and all that.
Because why?
Because what do we know are the real risks,
the real dangers?
We hear it's bad, but I never hear like,
how exactly is it bad?
Yeah.
Yeah, I mean, I do think that there broadly
is a very negative narrative when it comes to screen
time.
And I don't know if that is always warranted based on what we know from the research.
What we actually know is that it's more of a mixed bag, right?
Like the effects of screen time really depend on what's happening during that screen time
and on who the person is.
People have very different actions to the same experience
on their screens. So there's a lot that goes into it. But when it comes to thinking about the risks
of screen time, I would say there's two broad categories of risk. So one is just around the
time spent and concerns that that time is getting in the way of other things that are important for our wellbeing,
whether that's spending time in person
with friends or family, or spending time outside,
being physically active.
When screen time starts to really get
in the way of those things,
then I think that that certainly can be a risk.
The other category I would say is around
the content we're seeing on our screens.
We know that there's a lot happening,
for example, when we're scrolling social media,
there's a lot we see that maybe is not the best
for our wellbeing, is maybe not making us feel our best.
And so I think that's another risk as well.
That's certainly true that if you're on your screen,
you're not doing something else.
And what else could you be doing?
Exactly, or maybe you are, but you're not really totally
present in whatever that other thing is that you're doing.
Well, there's a big problem.
Because that drives me crazy, and I'm sure
it drives a lot of people crazy, when you don't have someone's
full attention when you're talking to them and they think it's
fine for them to talk to you and be on their phone scrolling or texting to somebody else.
I find that so rude but it's not just rude, it's like, well I guess it is just rude. It's like
you're not important enough to get my undivided attention. Yeah, you know, it's funny, there's actually in the research, psychologists have kind of come up
with all these different names for that exact phenomenon, because it is so common. So there's
a word called technoference, meaning technology and interference. Typically, that's used in like
parenting work. So where technology is really interfering with interactions that parents are having
with their kids.
And then there's another term that's kind of funny called fubbing, which is basically
phone and snubbing, meaning typically used in more like partner and friend kind of research.
So thinking about when we're on our phones and in the presence of friends or partners,
and that is in some ways, you know, we're snubbing them because we're not giving them our full
attention. And there is some evidence that, you know, unsurprisingly, that that experience
can have negative impacts on the relationship, on our sense of connection and relationship quality,
but also on, you know, our mood and our and relationship quality, but also on our mood
and our wellbeing.
I think we often think that spending that time
on our screens is gonna make us feel better
or less bored or whatever it might be.
But actually it does tend to have a more negative impact
on our mood.
Well, I think everyone would agree with what you just said
because there are times when everybody,
I mean, probably even you,
likes to just scroll mindlessly
through some social media something for a few minutes,
but it's like junk food.
It doesn't satisfy anything other than in that very moment,
but there's no other satisfaction to it.
Yeah, there's an interesting study actually that came out last year, which
I think really illustrates this, where it was with college students and they
essentially had college students in a waiting room, like waiting to what they
thought was participate in the actual study.
But half of the students, they had wait with their phones
and half of them, they had wait without their phones.
And the students who didn't have their phones
thought that they were going to feel worse,
thought they were gonna be bored,
they thought it was gonna be awkward,
kind of waiting around all these other students
with no distraction of their phones.
But actually in the end, unsurprisingly,
they ended up feeling better.
They ended up reporting better mood
at the end of the study,
because they ended up socializing
with the people around them
and weren't as distracted by their devices.
So I think that what we think is gonna feel good
is not always the thing that ends up
actually making us feel good.
What did they do instead? Were they just sitting there with their thoughts or were they reading
a book or what were they doing? No, yeah, so they provided some kind of entertainment for
those students if they wanted it. I remember this particular detail of this study is that they had a
giant Jenga game in the room in case students wanted to play
and some other stuff around.
But for the most part,
they were just waiting with other students.
So I think it was more about the socializing
where they ended up striking up conversations.
Well, that's the thing is scrolling on your phone
is a solitary activity
and you can see lots of people together, but they're all on their
phones. And so they're not really together and taking advantage or getting the benefits from
the socializing part of it. They might as well just be home in their room.
Yeah, you know, one of the things that we know about, about screen time and phone use is that,
you know, as I said before,
I think there are ways that it can be done
where it can promote our wellbeing
and ways where it can really interfere with our wellbeing.
And part of that, I think really comes down
to the social aspects.
So if we're using, you know,
our phones to promote connection, social connection, whether that's, you know,
we're sending a text to a friend to check in on how they're doing. Maybe we're sending
someone a message to make plans to meet up. Like those kinds of things obviously are going
to be good, are going to make us feel better. But if we're using our phones in ways that
are interfering with social connection, whether that's, you know, we're sitting on our phone
scrolling and looking at how much fun everyone else is having on social
media, or we're sitting on our phones when we should be interacting with the
people around us. Those kinds of activities are going to have a more
negative impact.
You know, I'm really curious to know, because we often talk about how other
people inappropriately use their phone or they're on
screens too much. But how do people feel about their own use of screens and their own time on
the phone? Do they think, yeah, I probably am on it too much, but, or do they think, no, I've got
this under control. It's other people who have the problem. How do people feel about their own participation in this?
That's a good question.
My sense from the research is that there's certainly
a good portion of people, I think probably the majority
of people, who feel like they spend too much time
on their screens.
I think that that's a pretty common experience.
Of course, there are plenty of people out there
who feel good about their screen use,
but I do think it's common for people to feel like
they are spending too much time
and to not be happy about that.
And yet probably don't do much to remedy
a concern that they admit they have.
Yeah, I think that part of what makes us so
challenging is that the screens that we're using right now,
phones in particular, smartphones,
in many cases the apps we're using on those smartphones,
are really designed to attract our attention,
to be hard to put down.
We know that there are features of our devices,
like notifications, which sort of ping and remind us
to come back to them.
Or if we're on social media, something like an endless
scroll where there's a social media feed,
there's no end to the feed,
and so it makes us want to keep going.
These kinds of things really make it so that we are inclined
to use our devices more.
I want to ask you if you think that we're at the point now
where phones, screens are becoming, I don't know,
a crutch or a habit maybe.
I'm speaking with Jackie Neese.
She is a psychologist and assistant professor
at Brown University. and she writes the weekly
newsletter TechnoSapiens.
I'm Amy Nicholson, the film critic for the LA Times.
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So Jackie, it does seem to me that,
especially with young people,
that picking up their phone is a habit.
It's like they can't not do it.
Go to a doctor's office and people are in the waiting room and I
actually went to a doctor not long ago and was struck by this woman who was
sitting there reading a real book and I thought, wow, look at her.
That's so rare. But in the old days, you know, the doctors used to put
magazines in their waiting rooms because that's what people did to pass the time.
Now it's just habit.
You sit down, you whip out your phone
and you stare at it until they call your name.
Yeah, I think a lot of our use is really,
yeah, as you're saying, really habitual,
really sort of mindless.
It's not necessarily a choice we're making always
to pick up our phone or to do a
certain activity on our phone. It's really more that it's just automatic at this point. We've
sort of gotten in the habit of using it a certain way. That's one reason why I think that, you know,
one thing, one first step we can take to try to improve our relationships with our devices
take to try to improve our relationships with our devices is to think about using it more mindfully. So less mindlessly and more mindfully. Meaning just taking a step back and really
trying to be aware of the times when we reach for our phones, you know, that sort of automatic
unlocking behavior that so many of us do. And really trying to think about when we're using it and why like what it what's the purpose so that's a good
probably a good place to start is to start thinking about why you're using it
but but what else because that that's yeah a great idea but it's a little vague
it's like well yeah be more mindful yeah I know but I'm sitting here and I have
nothing to do so I'm gonna whip out my phone. And, but like, what's the plan?
What's a way to approach this?
Yeah, it's a great question.
I think so the first thing of course is to be aware, right?
To know, like think about, you know, when we're turning to our device, what exactly we're doing on there and when that's feeling like a problem to us.
Right? exactly we're doing on there and when that's feeling like a problem to us, right?
So for many people, this is something like they're happy to use their phone for utilities,
things like Google Maps to get directions somewhere,
or they want to be able to make phone calls,
things like that that are more utilities,
even like they want to be able to listen to a podcast like this one or to music.
So maybe those are things that they
want to be able to do on their phone.
They appreciate that. They don't feel like it's getting in the way.
But then there are other activities they might start to recognize
are the culprits for things that are not making them feel as good.
For many people, that's things like mindlessly scrolling social media,
or maybe automatically reflexively checking email or checking a news app.
Those kinds of things tend to come up a lot.
But there are also a lot of tools that you can use.
You know, on the iPhone, there is the screen time setting.
You can go into your screen time settings.
You can set time limits on certain apps
or you can block apps at different times of day
using settings like downtime.
Android devices also have a similar feature through their digital well-being tools.
And then the other thing I would say is just outside of the sort of like technical side
of things, there are things you can do just in your day-to-day habits as well to try to reduce your mindless use
if that's what you're looking to do. So you can try to set phone free times of day, whether that's
meals or other times. You can try to set phone free locations of your house. So certain places
where maybe you decide you're not going to use your phone, certain rooms or maybe on the couch or something like that.
I think you can talk to your family and friends about what sort of the phone guidelines are going to be
when you're spending time with each other, and that can go a long way.
My guess is as wonderful as those recommendations are, people just don't do them. They would be very hard for me to imagine to alter my use using those suggestions you just made.
I'll just take care of it myself. And I imagine most people don't follow those recommendations.
People do find it very hard to do this kind of thing. So in
many of the studies that ask people to reduce their use of
their phones or of social media, the compliance is somewhat low,
meaning that it's hard to get people to do this. It's just
yeah, it's just tricky for a lot of people. But in most cases,
they do find that when people stick to it,
when people do it, they do end up reporting improvements
in mood and well-being and other factors.
So it can certainly make a difference.
Well, I've had that.
The other thing I would note that can make a big difference
in terms of well-being is trying to reduce phone use
around sleep.
We know that our device use can really interfere
with sleep when it's keeping us awake at night.
One thing that seems very simple,
but can make a big difference is charging phones
outside of the bedroom when you go to sleep.
And there is some evidence that that can improve both the length
and the quality of people's sleep.
Even though you're not on it, it's just not in the room.
So you can't be.
But what is right?
Well, I think when it's in the room, the problem is that there's too much
temptation for many people to grab it.
So if you, you know, or maybe it's making noises
in the middle of the night that's waking you up.
Or, you know, if you can't fall asleep
or you wake up in the middle of the night,
you reflexively go to check it
and then that keeps you awake longer.
So sort of having it out of sight, out of mind
can make a big difference.
Well, one of the big concerns about screen time
that you hear was probably the first big concern is about
kids and video games and all of that. Where are we? What does the research say about all
that? Is it horrible or not or what?
Yeah. So with video games, I think that where the research stands right now is that, unsurprisingly, it depends, right?
It depends on who the kids are.
Kids are affected in very different ways when they're using video games.
It depends on what exactly is happening in those video games.
Generally, you know, there was a big concern for a while about violence in video games. Generally, the research does not support any long-term links between playing violent video
games and, you know, violent or aggressive outcomes in the long term.
So some of that concern, I think, has been somewhat overblown.
That said, I think there's good reason for parents to be aware of the
kinds of things that their kids are being exposed to in video games.
Here's something I think a lot of people wonder about because for decades people
have gone to bed, watched TV, and then gone to sleep. I haven't heard a whole lot
about that being a problem, but there's a lot of caution about looking at a screen like a phone or a tablet
before bed that that screws up your sleep. What's the difference between the TV and the screen,
the computer screen? Yeah, so I think in terms of the actual technology and the effects,
there's nothing specific about a phone or a tablet that's inherently worse than
a TV, right? Like it's still a screen that's being watched and that's it. I think the, you know,
practically there are some differences. So with a tablet or a phone, obviously it's, you're not
having the same experience of with the TV you turn
it off and it's off and that's sort of it and then you get up and you walk away
with a tablet or a phone of course it it often comes with you and so that makes
it just a different experience in terms of the ease of putting it away of
stopping to use it the activities that you do on a phone versus,
or a tablet versus a TV, also sometimes differ.
So you might be using more social media
or other apps on a phone versus on a TV.
Maybe you're watching more shows.
And with a TV show, it tends to have more
of a definitive endpoint, right? Like an episode it tends to have more of a definitive end point, right?
Like an episode ends and that's kind of the end versus when you're scrolling on social media,
it sort of can continue on forever.
Well, it's a topic that is the subject of a lot of conversation and concern, maybe especially for parents.
But it's a topic, I think, that everyone's concerned about how much time we're spending on screens and
What we're not doing because we're spending so much time on screens
Jackie Neesey has been my guest
She's a psychologist and assistant professor at Brown University and she writes a popular weekly newsletter called
Techno sapiens and if you'd like more information to that, there's a link to Techno Sapiens in the show notes
for this episode.
Jackie, thank you for coming on and talking about this.
All right, thank you so much, Mike.
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How the human body works is so fascinating and so complicated
from how we use food for fuel,
how and why we age and can't live forever,
why we sleep, why we have to sleep,
yet sleep leaves us vulnerable to so many things,
how our immune system keeps us alive,
and how evolution changes us ever so slowly.
Here to explain some of these intricate bodily systems and how we can keep them working smoothly
is Dr. Dara Ennis.
He is a scientist and researcher who has worked at both the University of Oxford and the University
of Glasgow.
He is author of a book called The Body, Ten Things You Should Know.
Hi, Dara.
Welcome to Something You Should Know. Well, Dara, welcome to Something You Should Know.
Well, thanks very much for having me.
So the human body, our bodies, like every other living thing, gets older and ultimately dies.
From a scientific point of view, why must that be? Do we know why that is? Because it seems like we certainly live longer
than we used to, but ultimately we die.
Well, the why do we age is certainly a question
with an answer.
There's very deep rooted ways that our cells
and the cells of all living things work
that makes them age.
And one of the main things,
as anybody who works on aging will
understand is that our DNA, the code that makes us what we are and are the
instructions for us being alive has a lifespan in and of itself.
So, you know, every high school student knows that DNA gets copied, but what
they don't realize is every time it gets copied, that copy is only a tiny
fraction smaller than the original. But what they don't realize is every time it gets copied, that copy is only a tiny fraction
smaller than the original. And eventually it's too small and it just goes away. So that in itself
is a limit. It's a ticking clock and there's nothing we can do about it. So yeah,
that's a bit of a problem for people who want to live forever, I'm afraid. But even people who get older and die from diseases that are normally associated with old age
die at different ages.
Some people die in their 70s or their 80s or 90s,
and some people make it even longer than that.
So there is a clock because ultimately nobody
gets any older than whatever the maximum age is,
but there is a clock.
Well it's a maximum clock. So most people don't reach that. That isn't the sort of
critical factor in what ends up finishing us off essentially. So we'll all get old
and we'll all age, but there are other factors that will damage ourselves, damage our DNA, you know,
exposure to sunlight makes our skin look older.
Other lifestyle choices, what we eat, you know, what we do, how much exercise we take,
how happy we are, how stressed we are.
So it can even be a case of you can sort of think yourself young and that is literally
going to be physiologically true because stress responses age ourselves and aged cells go into a state called senescence,
which is effectively where they shut down and start to die off and that's contagious.
Other cells around it can pick it up and the stress response is a big factor in senescence.
So if you're a very stressed out person with a bad lifestyle, you're going to age a lot quicker than someone who's just happy-go-lucky and looks after themselves.
So you can maximise your chances of being younger for longer, but not forever.
It's never forever, is it?
Unfortunately, no.
So let's talk about blood and how blood gets circulated all throughout the body and how that all works.
Well, it's driven obviously by the heart, but our blood vessels are quite elastic and
they swell and shrink as the pulse rate from your heart comes.
So that elastic motion helps maintain blood pressure and it's the pressure of the system
that keeps it all moving.
So if you have a very closely pressurized system and a pump, it means that it can reach right to the end of these tiny capillaries that are potentially a couple of meters away,
or a meter and a bit away from your heart. And yeah, it's just a constant pressurized system with a constant flow.
It's astonishingly efficient considering it's driven by a lump of muscle about the size of our fist that doesn't make very much noise.
If you ever see how much noise and energy a water pump uses to pump something that long,
it's massively more efficient.
Evolution beats engineering every time.
So it seems like a big question, but since you tackle it, this whole idea of about getting and using energy,
how food becomes energy, how we spend energy, I never really, I get that it happens, but I'm
not sure I have any idea how it happens. The main thing to remember is that, you know,
by the laws of physics, you can't make energy, you just change its form. That's all you do.
You just mess about with the structure of it. So energy can't be made, it can't be destroyed. So we take
the energy from chemical bonds in our food and we just put it into a system that ourselves can use.
And it's really, really clever and massively efficient how it does so. And it's largely driven
by mitochondria, which are small organelles in our cells. And the
fun thing is most scientists think that they were originally independent organisms way back in our
evolution when we were like single cells that were eaten essentially, but survived. And because they
were so good at providing energy, they become part of our setup. So they're an alien life form that over tens of millions of years has just come
along with living animals and helps them provide their energy.
So that massively makes it more efficient.
And yeah, it's, it's just, it's a series of different reactions that make food
energy into the energy that ourselves can use.
And it's amazing.
It's astounding to be honest.
So you've mentioned a few times how, you know, this is amazing and this is really efficient.
And my guess is that the systems get that way over time through evolution. But I don't know
that we really understand. I don't think evolution works the way people think it does.
No, no, I do quite a lot of, you know, public events and things and people ask me science
questions and I love that.
I really do because it's my real passion.
But a lot of people say things like, oh, you know, in 10,000 years, will we have much longer
fingers because we type and that's how evolution works.
And it really isn't evolution only works if something makes you more likely to survive
and have children.
Those two things have to be together.
So if it doesn't make you more likely to reproduce, then evolution throws it away.
And that's it.
And it's random, completely random.
But over enough time, it will eventually, you know, get us from one of those single
celled organisms to the one that can get the bus to work.
But the amount of time is absolutely immense.
You know, you're talking tens or possibly even over
hundreds of millions of years.
Well, that phrase you used about evolution throws it away.
I think that's where people get confused that it isn't like one morning.
The heavens say, well, you know, we're not going to need a tail anymore.
So let's just knock that off because we don't need that.
It doesn't work that way.
Very rarely.
Like you will occasionally get a very bizarre mutation that will completely change an animal.
It will change its color or it will do something really, really weird to it.
But yes, most of the time the change is extremely gradual.
And quite often it's because there's a cost to everything.
So having any part of your body or doing any action
or anything, producing anything,
costs the cells in your body something.
You have to make the proteins,
you have to do all of this kind of thing.
Or there is a cost as in it makes you more likely that another animal will eat you
or it makes you less likely to reproduce.
And if you're in a competitive environment
and you as an animal change color, you know, you get a red stripe or something.
And suddenly that means the females are no longer interested in you.
They're not going to mate with you because you've got this red stripe.
That's never going to be passed on because you don't reproduce and the mutation disappears and
it's just literally thrown away from the population. But if it's the other way and the red stripe
suddenly means all the females are interested in you, then gradually over time you'll speciate,
so you'll become the red striped version of your animal and you'll produce lots and lots of children.
And that's it. It's purely this is the bit that people don't understand.
It's it's not about growing bigger teeth to fight off the predators.
It's just about are you going to survive long enough to pass those genes on?
And they're kind of like, you know, memes or viral things on the Internet.
You know, it doesn't necessarily have to be good.
It doesn't necessarily have to be brilliant.
It just has to be popular. And that's it.
Why do we sleep?
Oh, that's a weird one, isn't it? So by any logical sense, anything that you think
about an animal going to sleep is a terrible idea. Like it's so bad for it. It makes
you completely vulnerable. And you would think that evolution of all things, this really strict,
you know, filter that takes away anything that's dangerous will get rid of sleep.
But it just can't.
It seems to be deeply inbuilt into not just humans, but like almost all animals,
like flies sleep, fish sleep, dolphins and whales sleep, even though they're like
they have to, you know, breathe and all this kind of thing underwater.
And it seems so inbuilt to how our nervous system specifically work that we can't get
rid of it.
So the cost of getting rid of it is way too high.
And if you ever meet someone who's sleep deprived, you very quickly realize why, because
it just messes with us so badly.
So it must do something really, really special for us to devote that much of our life to it.
Oh, it absolutely does.
So our brain function completely relies on sleep.
So we can't get completely to the bottom of this very easily because the ethical
considerations of doing sleep deprivation studies means that they very rarely go past two or three days without sleep because it's so bad for you.
But in the ones that they have done are ones where people have had medical problems that
kept them awake. You lose all critical function, your brain stopped working completely. It's
almost like you've been drinking, you know, it's that kind of level of loss of motor
control. You become emotionally problematic. You start overeating because your hormone been drinking, you know, it's, it's that kind of level of, of loss of motor control,
you become emotionally problematic, you start overeating because your hormone system stopped
working properly. And a really key thing as well, is that your brain washes itself at
night time. So there's been studies where they've watched people when they're going
to sleep, I am through MRIs and, and CAT scanners and things. And they've seen pulses of cerebrospinal
fluid going over the brain during sleep. And they really think that this downtime, this
maintenance time of sleep helps remove bad things for your brain, toxin buildup, but
especially things like misfolded proteins. So misfolded proteins can lead to Parkinson's
disease, to dementia, and and all sorts of other neurological
problems. And without sleep, it's not able to do that because our brain is just so busy all of
the time when we're awake. It's always got so much to do that it can't have maintenance. So
effectively sleep is brain maintenance mode. You need to let the janitors in to clean up.
So here's, I'm so glad you tackle this in your book because how many times have we heard
about how the body defends itself?
You have an immune system in it, but nobody knows what that means or how it works.
It's just, well, you know, I didn't get a cold and he did because my body defended itself.
But how?
I don't know what that means.
Yeah, I think a lot of people,
especially since the pandemic,
got a very skewed and peripheral idea
of what the immune system is and what it does,
because it was kind of covered on the news,
but never in depth.
And I've always used analogies to explain things to people.
And I think a great way to look at it
is like a security system with guards.
And you've got two different systems.
One is your innate system, which just works away on its own.
If it finds anything foreign, it'll attack it and it'll run a fever and it will provoke
that kind of immune response very, very quickly.
But then you've got your adaptive immune system, which is why we become
immune to things. So this is if it sees something it recognizes from before, it will instantly
find it and attack it. It's way more efficient, but you have to have been exposed to it before.
And that's the whole reason why vaccines work is because vaccines prime that innate
system. It's kind of like giving your security guards a wanted poster,
going, if this guy comes along, you make sure you catch him real quick.
And a lot of people don't understand how it works.
There's a lot of disinformation out there because there's a lot of money to be made
trying to tell people that they can not catch a common cold if they
take this supplement and things. But most of it's nonsense.
But is it your immune system when you cut yourself and the cut heals?
It's a mixture. So your skin is one of your best defenses, actually. We're constantly
bombarded by viruses and bacteria and funguses, and people don't realize this because they're
so small. And almost all of them land on your skin and die. You know, if you're a scientist and you're doing microbiology, you have to,
you know, sterilize everything and have a flow of sterile air, or you have to
have a Bunsen burner to, to, um, make the air above your station rise up and keep
all of the spores and all of the bacteria off it because they're everywhere.
They're ubiquitous.
And if you cut yourself, you open the gates, you know, so your immune system
makes sure it doesn't get infected. And then your body repairs it in a different way. So it's not
your immune system fixing the cut, but it's making sure that nothing gets into that cut that will
make it infected. And that's way more important to be honest, because infections until relatively recently in human sort of technology, an infection
like that could kill you because once they're in, that's when these guys, the bacteria and things
cause such trouble. But going back to like catching a cold, there are some people who seem to get
sicker more often than others, exposed to more or less the same things. And, you know, my wife who works in a hospital, she never gets sick.
And so the assumption is, well, she doesn't get sick because she's been exposed
to so many illnesses that she's built up this immunity to it.
I don't know if that's true, but she never gets sick.
Part of it is so having an exposure on a constant basis boosts your immune system.
Your adaptive immune system recognizes more pathogens. You're more primed to do it.
But I know this is going to sound a little gross, but a very large part of the reason why
health care professionals don't get sick is because they wash their hands properly.
If you're working in a in a healthcare environment,
you're probably very carefully washing your hands for a minute or two minutes
at a time, maybe 20 times a day.
That's a very large reason why we get sick is because we pick up things
or we shake hands with someone or we touch the door handle and then we rub our eyes
or, you know, we pick something out of our teeth and it gets into our body and it escapes.
But yeah, there's a little bit of a boosted immune system to it, but some of it's just good practice.
What's one thing about the body that you think people maybe don't understand as well as they should, or there's a lot of misinformation about it?
I mean, you're out speaking to people all the time.
What is it you think, if anything, there is confusion about?
speaking to people all the time. What is it you think, if anything, there is confusion about?
I think one thing that a lot of people get wrong is nutrition.
There is so much commercial pressure
from companies who are trying to sell
what are considered healthy food.
And a lot of people don't understand
the genuine need for a healthy diet to keep yourself healthy.
And they don't understand that a lot of the things, the supplements they're being sold
or, you know, the miracle food thing, a lot of it is nonsense or it's marginal at best.
So you have people who, you know, will take some miracle, you know, powdered seaweed supplement,
but then will eat nothing but fast food and
they're wondering why they're not doing well.
The overriding dietary advice since probably the first century is to eat a wide varied
balanced diet that's largely based on fruit and vegetables, fresh fruit and vegetables.
I don't know if they did it in the US, but in the UK and Ireland, they said five portions a day. That's what they said. If you have five portions of fresh
fruit and veg a day, that's a good start. It was actually meant to be 10, but they realized
if they told people they had to eat 10 different fruits and vegetables a day, they would just say,
no, we're just going to give up. So five is kind of the bare minimum and almost nobody eats five
portions of fresh fruit and veg a day.
Almost never. Yeah, nobody does. Who does?
Yeah, nobody does. But if you really genuinely want to have a healthy diet,
it's eat almost no processed food and almost everything is processed food, which is a big
problem. But base it on fresh fruit and veg and cook things yourself from scratch where possible.
But that's not achievable
in the modern world, unfortunately. So, you know, I wish there was some fun way of saying
a healthy diet, but unfortunately, healthy diets are what doctors have been telling us
for since like the 1920s.
And lastly, what happens when we die?
So this is one I wanted to do and I wasn't sure that, you know, people would want to read it, but it's actually
turned out to be great.
It's been very popular.
Um, and I don't mean this in a spiritual way.
If anybody's thinking that way, this is what happens to your body when you die.
Cause a lot of people, there's big taboos about death and, you know, we, we like to
pretend that things don't happen, but our bodies go away.
They're gone. They're gone fairly soon. Unless you're in very specific circumstances,
within a few decades, there's only slight remains of bone, some hair and, you know, some fillings,
or if you've got a metal implant or something, that's all that's left. And that process is,
I think, fascinating.
You know, what happens when you stop being a person and you suddenly become a body, literally
a body. And I think a lot of people don't realize what does happen to your body. And
some of the fun things, well, fun, interesting things are that not all of your cells will die
at the same rate. So, you know, your brain cells die almost straight away
because they need so much energy and so much oxygen. But your immune cells can last for days
and days. You could have a dead body and you'd have little white blood cells four or five days
later just drifting around and not realizing that the body is dead because, well, they're not sentient
so they'll never realize. But yeah, I thought it was, it was important for people to address this because I think we shy away from it because it's a difficult subject.
Well I know I've certainly learned a lot and understand things about how the human body
functions that I didn't know before. I've been talking with Dr. Dara Ennis. He is a
scientist and researcher and author of the book, The Body, 10 Things You Should Know.
There's a link to that book at Amazon in the show notes.
Dara, thanks for coming on and talking about this.
Well, thanks very much for having me, Mike. It was brilliant talking to you. I really enjoyed it.
Of course, you know that talking on a cell phone when you're driving is a bad idea because it's very distracting
But it turns out that driving a car while your passengers are talking on a cell phone is also very distracting
In fact listening to anybody talk on a cell phone is distracting because you're only hearing half of the conversation
It's called a half a log and it reduces your cognitive function.
So for example, if you're driving in your car and someone else in the car is talking on the phone,
it's almost impossible to tune it out. So your brain is frantically trying to make sense of a
conversation where you're only hearing half of it. The researchers that did the study point out that when we overhear a conversation normally,
we actively try to predict how the conversation will go.
And when you only hear one side of the conversation,
your brain has to work harder to do what is,
you know, pretty much impossible.
So with less of your brain available to focus on driving,
you're more at risk for an accident, which
is a good reason for everyone in the car not to talk on their phones.
And that is Something You Should Know.
Something You Should Know is produced by Jeffrey Haverson, Jennifer Brennan, and our executive
producer is Ken Williams.
I'm Mike Herothers.
Thanks for listening today to Something You Should Know.
From the podcast that brought you to each of the last lesbian bars in the country and
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This is your host, Sara Gabrielli, and I've spent the past year interviewing history-making
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For 11 years, every night women slept illegally on the common.
We would move down to the West Indies to form a lesbian nation.
Meg Christen coined the phrase women's music, but she would have liked to say it was lesbian music.
And that's kind of the origins of the Combahoover collective.
You can listen to Cruising on Apple Podcasts, Spotify, or wherever you get your podcasts.
New episodes air every other Tuesday starting February 4th.
Do you love Disney?
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I'm Megan Megan the Magical
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