Dr. Darragh Ennis
Appearances
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
Well, the why do we age is certainly a question with an answer. You know, 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, you know, 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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
So, you know, every high school student knows that DNA gets copied. But what they don't realise 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, you know. So that in itself is a limit. It's a ticking clock and there's nothing we can do about it.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
So, yeah, that's a bit of a problem for people who want to live forever, I'm afraid.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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, you know, finishing us off, essentially. So we'll all get old and we'll all age. But there are other factors that will damage our cells, damage our DNA. You know, exposure to sunlight makes our skin look older.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
the 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 our cells 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
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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 gonna age a lot quicker than someone who's just happy-go-lucky and looks after themselves. So you can maximize your chances of being younger for longer, but not forever.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
Unfortunately, no.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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,
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
it means that it can reach right to the end of these tiny capillaries that are, you know, potentially a couple of meters away or a meter and a bit away from your heart. And yeah, it's just, it's a constant pressurized system with a constant flow. It's astonishingly efficient considering it's driven by, you know, a lump of muscle about the size of our fists. That doesn't make very much noise.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
If you ever see how much noise and energy a water pump
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
The main thing to remember is that 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 our cells can use.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And because they were so good at providing energy, they've 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 just, it's a series of different reactions that make food energy into the energy that our cells can use.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And it's amazing. It's astounding, to be honest.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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...
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
But the amount of time is absolutely immense. You know, you're talking tens or possibly even over hundreds of millions of years.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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, uh, it's because there's a cost to everything.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
So having any part of your body or doing any action or producing anything costs the cells in your body something. You know, 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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And if you're in a competitive environment and you, as an animal, change colour, 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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And that's it. It's purely, this is the bit that people don't understand. 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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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 almost all animals, like flies sleep, fish sleep, dolphins and whales sleep, even though they have to breathe and all this kind of thing underwater.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And it seems so inbuilt to how our nervous systems 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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
Oh, I, 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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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 stops 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 system stopped working properly.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And a really key thing as well. is that your brain washes itself at nighttime. So there's been studies where they've watched people when they're going to sleep through MRIs and CAT scanners and things, and they've seen pulses of cerebrospinal fluid going over the brain during sleep.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And I really think that this downtime, this maintenance time of sleep helps remove, you know, 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 to all sorts of other neurological problems. And without sleep,
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
One is urinate system, which just works away on its own. And it's, 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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
If you're a scientist and you're doing microbiology, you have to sterilize everything and have a flow of sterile air, or you have to have a Bunsen burner to 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. If you cut yourself, you open the gates, you know?
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
Part of it is. So having an exposure on a constant basis boosts your immune system. Your adaptive immune system recognises 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 healthcare professionals don't get sick is because they wash their hands properly.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
you know, if you're working 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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And they don't understand that a lot of the things, the supplements they're being sold or the miracle food thing, a lot of it is nonsense or it's marginal at best. So you have people who will take some miracle powdered seaweed supplement, but then will eat nothing but fast food. And they're wondering why they're not doing well.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
The overriding dietary advice since probably first century is to eat a wide, varied, balanced diet that's largely based on fruit and vegetables, fresh fruit and vegetables. And 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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
It was actually meant to be ten. 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. Yeah, nobody does. Who does? Yeah, nobody does.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
But unfortunately, healthy diets are what doctors have been telling us for since like the 1920s.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
So this is one I wanted to do, and I wasn't sure that people would want to read it, but it's actually turned out to be great. It's been very popular. 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. Because a lot of people, there's big taboos about death,
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
And we like to pretend that things don't happen, but our bodies go away. 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 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.
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Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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 realise 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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
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.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
But yeah, I thought it was, it was important for people to, to address this because I think we shy away from it because it's a difficult subject.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
Well, thanks very much for having me, Mike. It was brilliant talking to you. I really enjoyed it.
Something You Should Know
Your Brain on Screens: Myths and Facts & How Your Body Keeps You Alive
Your brain washes itself at nighttime. 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. They really think that this maintenance time of sleep helps remove bad things for your brain, toxin buildup.