Okay.
One of Michaels greatest passions has always been
the extraordinary secrets of how our bodies work.
Okay. Yeah, that s good.
He spent several months with the production team.
travelling far and wide
for this brand new series on the human body.
Just look.
The family and I are delighted to introduce it to you.
Michael even persuaded me
to participate,
tipping him upside down.
Blimey.
As well as filling his ice bath
All in the name of science.
Right.
And I'm sure he would have enjoyed the program.
We're heading off on an extraordinary journey
We're heading off around the human body.
And if you give us a little chuckle...
MICHAEL CHUCKLES
'Have you ever wondered
'why we get creaky joints?'
'Does your body hold the power to stop cancer from multiplying?'
How do you remember to breathe?
HE INHALES DEEPLY, EXHALES
'I'll be tracking down answers to lots of burning questions.'
HE EXCLAIMS, LAUGHS
I feel quite a strong desire to urinate.
But don't. LAUGHING: OK.
'From what exactly is in our farts...'
This device, which we colloquially refer to as the Thunder Funnel...
MICHAEL LAUGHS
'..to how long we take to digest our food...'
Are you wearing it every night? Absolutely.
'..I'll show you how we can all live healthier, longer lives.'
This is one of
for a very long time.
'And I put my body to the test...' Hey.
'..to help you at home...' Oh!
'..understand yours.'
That's stuck.
Get ready to see yourself...
..in a whole new light.
'This time...'
My 66-year-old hips still get me from A to B.
'But as we get older, the risks that a simple fall
'will lead to breaking a bone increases,
'so what can we do to keep our bones stronger as we age?'
It's rather brilliant, isn't it? Oh, it's an engineering miracle.
'If you've ever felt
'like your handwriting isn't as neat as it used to be,
'or maybe you feel shakier than you did when you were younger,
'you're not alone.
are affected by tremors.
'For the first time, our cameras follow
'a pioneering brain surgery, giving real hope.'
isn't he? Yeah.
'And almost every five minutes, somebody's life changes forever
'as their brain suffers a stroke.'
I always think you're only one blood clot away
from a life-changing event.
'So I try out an ingenious new way
In this series, we'll explore the wonders of the human body,
how it adapts and changes to the countless challenges
it often faces.
Around a quarter of all deaths in the UK
are linked to cardiovascular problems.
To avoid becoming part of those statistics,
I'm about to take a close look
at one of our most vital organs - the heart.
The heart is a powerful muscular pump,
roughly the size of your fist,
constantly at work, pushing blood around your body.
And when the heart fails,
it can happen suddenly, without warning.
Well, I'm in Oxford to try out a brand-new test,
which was developed here
and which claims to be able to predict heart problems
long before you have any symptoms.
I am feeling a little bit nervous.
I know I'm an increased risk,
but when I do the test,
that's gonna tell me just what the risk is,
what they're gonna find out.
'Like many others, I've lost loved ones to heart failure,
'including my dad, who died when he was just 74.
'That's only eight years older than I am now.
'Before I had the test, Professor Antoniadis,
'who leads the team here at Oxford University,
'explains what makes this test such a breakthrough.'
This is a brand-new technology, and essentially, what it does,
it looks into the fat that surrounds the heart vessels,
and by analysing the fat,
we can tell whether the arteries themselves are inflamed.
And these are the arteries that will give the heart attacks. Wow.
So you're peering into the future,
with a greater degree of accuracy, you hope? Yes.
You ready? Yes.
Painless.
'First, a special dye is injected into my blood
'so that my arteries will show up on the CT scan.'
Very smooth.
You're gonna move in and out three or four times in total.
We'll get you to breathe in and hold your breath each time.
AUTOMATED VOICE: 'Please breathe in and hold your breath.
'Start breathing again.'
Like your other organs,
your heart needs a constant supply of fresh blood,
which it gets from the coronary arteries
that wrap around the outside of your heart.
By the age of 50, the walls of
to a build-up of fatty deposits, called plaque.
You can think of this
as a bit like the pipes in your house getting clogged up.
The build-up can make it harder for blood to flow through,
and this can increase the risk of heart attack.
The main artery...
'of dangerous changes in my arteries.'
yeah. Mm.
'And worryingly, they've found several places
'where my arteries are starting to get clogged up.'
Yes.
'Plaques can be prone to rupture,
'whether fatty or hardened ones, known as calcified plaques.
'What I'm looking at is a ticking time bomb,
'a potential heart attack coming down the line.'
So, these little nodules, which are plaque,
if one of those ruptured, it would kill me, yes?
Yes, that's correct.
MICHAEL EXHALES DEEPLY
Right. Calm.
'As many as one in two of us
'can develop plaques without symptoms.
'By using it, the Oxford team will soon be able to tell
'just how high my risk really is.'
400 miles further north, on the Fife coast,
Thomas Black knows just how devastating it is
when a vital organ goes wrong.
In Thomas's case, it's his brain which is not working as it should.
the roots because I'm shaking.
71-year-old Thomas has had his life turned upside down
by a condition called essential tremor.
It's ten times more common than Parkinson's
and is more likely to affect people over the age of 65.
It's all the little things that you never think about,
like working zips or brushing your teeth.
Essential tremor makes daily activities for Thomas,
and others like him, almost impossible.
I was in my mid-40s,
and I first noticed quite shaky right hand.
And then my mid-50s,
both hands were much shakier, and my head was shaking,
and it just got worse and worse and worse after that.
We were showing this
Brings back memories.
48-and-a-half years ago. SHE CHUCKLES
Nice to look back. It's nice to see hair!
SHE LAUGHS
Janet has been by Thomas's side, watching helplessly,
as his symptoms have got worse.
Tom was quite good at sort of not
Erm...
You know, like putting a key in the lock,
had to adapt the way he could eat.
The mugs were getting bigger for his soup with less soup.
The same for the coffees.
to stop the tremor.
They are now pinning their hopes on
Decisions had to be made. I had to go through various tests.
Today's the big day, and Thomas has been admitted
to Ninewells Hospital and Medical School for the operation.
Quite sore, but I'll be fine.
Neurologist Dr Tom Gilbertson is
It's one of very few treatments
to a chronic disease that's otherwise uncontrollable.
OK, Thomas, I'm just gonna move these pins forward slightly.
Mm-hm.
It's just for me to know where to put the local anaesthetic in.
With a head brace fitted to help reduce his shakes,
Thomas is about to have a form of brain surgery
that involves no actual cutting.
Instead, a powerful beam of ultrasound waves
will be focussed on part
It's not without risk.
If the beam strays even a fraction,
it could leave Thomas with loss of speech or paralysis.
It's fine. NURSE: Perfect.
Coming up, how does your body fight back when cancer strikes?
I planned and paid for my funeral.
With the growing cold-water craze,
what are the health benefits and what are the risks?
I'll reveal three surprising things
about your heart that could save your life.
When you exercise on a regular basis,
you actually grow a whole lot of new blood vessels.
And I find out my own heart attack risk.
I've got slightly sweaty palms. I must admit, I'm quite anxious.
'I've just had a new test that can accurately predict
'your heart attack risk long before it happens.'
We're looking to whether there are narrowings in your arteries
plaques, as you call them, atherosclerotic plaques,
which may break in the future, causing a heart attack.
'Worryingly, they've told me that
'I do have these life-threatening plaques.'
If one of those ruptured, it would kill me.
Yes. That's correct.
MICHAEL EXHALES
We all have a protective layer of fat on the outside of our arteries,
and this outer fatty layer can reveal
where an artery has become inflamed on the inside,
making it more susceptible to rupture.
If picked up in time, you might be prescribed medication
to try and reverse some of these changes.
'A healthy diet and at least 20 minutes of moderate exercise a day
'is also beneficial, whatever your age.
'So, what about my arteries?
'Is the damage still reversible?'
OK, moment of truth. I've got slightly sweaty palms.
I must admit, I'm quite anxious. This is your heart.
Around an inflamed area, the fat
The blue colour that you see here means that is water.
Blue essentially means
Exactly. So, these are the plaques that we have seen earlier
in the main artery.
You can see that in this area,
there is a little bit of inflammation. Yeah.
But overall to me,
it looks like a pretty much non-inflamed artery.
OK. So, I'm looking at this figure. That's the one that's jumping out.
So, this is your absolute risk... Yeah.
..to have a fatal cardiac event over the next eight years. OK.
Anything below 5% considers to be low risk.
Now, you are 5.9.
It means that you are just about where you should be.
So another way of looking at this is saying
I have a 94% chance of making it to 74,
and therefore a 94% chance of beating my dad.
Exactly. That's a very good way to put it.
It's not perfect. No.
So there's still some risk.
Yeah. I'm not gonna go away and eat cream buns. Don't worry. Exactly.
You can't imagine how relieved I feel,
I was awake last night thinking about it.
So, you need to try a little bit harder.
Bring this down. But you are nearly there.
'Exercise and a healthy diet can help.
'People in my position may also be prescribed statins.'
Wow. I'm almost faint with relief.
I'm gonna give you a hug because I was really, really worried,
I have to say.
Ah!
Well, that was stressful but also reassuring.
And at least I know now that it's unlikely
I will go the same way as my dad,
And I guess what it shows as well is
that if you look after this remarkable organ,
it will go on looking after you, hopefully for a long time to come.
You can cut your heart attack risk by as much as 30%
by eating less junk food
and more healthy fats, like oily fish and nuts.
Getting your cholesterol checked is also a good idea.
And of course, if you're at all concerned, do go and see your GP.
In the UK, heart disease is still one of the leading causes of death.
But there is another life-threatening condition
which one in two of us will face
Throughout our lives, the cells that make up our body divide,
they grow, and then they die in a very controlled way.
Sometimes, the mechanisms to stop cells growing are faulty,
to grow in an uncontrolled way.
In fact, one of the things that your body fears above all else
are rogue cells that are out of control.
So if rogue cells arise that try to grow
in a way that your body doesn't want them to,
then the body has lots of different ways to destroy them.
But sometimes, rogue cells are able to evade
all the attempts that are made to destroy them.
ECHOING: They escape, they grow. They become cancer.
Different cancers multiply at different rates.
Most breast and bowel cancers, for example,
seem to grow relatively slowly.
But if you have a cancer of your blood cells,
then symptoms can appear more suddenly,
and the cancer may spread more rapidly.
In this series, we meet people with extraordinary stories to share
that shed new light on how our bodies work.
In Dorset, 76-year-old Alan Peters has been diagnosed
with a type of blood cancer called a lymphoma.
It's lymphoma, stage 4B cancer.
They said that there wasn't really a great deal
that they could do to cure me.
Alan is grateful to have lived a full life.
For 30 odd years, I was a policeman in London,
and I was lucky enough to work with the Princess of Wales
for nine years as a personal protection officer.
But after Alan retired, he noticed worrying symptoms.
I thought it was COVID.
I went to the doctor two or three times,
and eventually, they sent me for a scan.
That's when we discovered there was a large lump.
Just about that time was when you turned up from Ukraine.
To hear this news about you, I was absolutely upset.
I decided straight away, we have to stay to help you.
Alan offered a home to Olena and her family,
and the support she offered in return was a huge blessing.
I had written myself off,
in as much as I wasn't gonna last much longer,
and, as you know, I planned and paid for my funeral.
Cara. Cara.
But then Alan was thrown a lifeline
approach known as CAR-T therapy.
After several rounds of the new therapy,
Alan is going back to Southampton to find out
if the treatment has been successful.
This is my sixth or seventh scan.
Being diagnosed with cancer can be not just physically,
but also emotionally devastating.
And for Alan, it's been a nerve-wracking wait.
I'm just a little bit tense because it's an important one.
CAR-T therapy is a way of boosting
the body's immune system to attack the cancer,
and it's being further developed by Professor Xian Lim.
Cancer cells are unfortunately sneaky,
and they can hide from the immune system...
so the immune system needs help.
We all have special immune cells called T cells.
Their job is to defend your body.
But cancers can hide from them.
So scientists take the patient's T cells,
modify them in the lab then re-inject them.
These new cells, nicknamed CAR-T cells,
now have the ability to track down cancer cells and destroy them.
Sadly, this approach isn't for everyone.
But has it worked for Alan?
Complete remission.
No sign of any disease whatsoever.
Yes! MAN: Well done.
That's good.
I was trying to keep a miserable face, watching,
watching you lot go, "Whoa, what's...?"
These scan images of Alan before he started the new therapy,
compared with his most recent scan, shows something remarkable.
Alan's body, once riddled with tumours,
now appears cancer-free.
Important to remember - never give up.
I never did give up.
I was just prepared. There's a big, there's a big difference.
Thanks to breakthrough treatments,
we're now six times more likely to survive cancer
than we were 40 years ago.
to undergo a radical new treatment.
Everything is riding on what happens today.
Will he finally get relief from the debilitating tremors
that are ruining his life?
We're trying play some music for him in the, er...
There you go, that's you all set.
Our cameras have been given rare access
to follow this ground-breaking procedure step by step.
of damage to healthy brain tissue,
he will have to remain awake the whole time.
If he develops slurring speech,
we know we're too far outside of the target.
Then we have to adjust our treatment.
The team is about to use
a high-powered ultrasound beam on Thomas's brain.
See how he goes here.
They need to zap a tiny cluster of cells
in a part of Thomas's brain called the thalamus.
By doing this, they hope to create a sort of circuit breaker,
which will stop his brain sending out too many confusing messages.
When you decide to move, your brain sends signals to your muscles.
At any one moment,
there are billions of signals buzzing around your head.
Normally, your brain can filter out the information you don't need,
but if you have essential tremor,
this filter doesn't seem to work and the signals get confused.
And that could be what's causing Thomas's uncontrollable shaking.
Thomas's shakes are so bad
that even trying to draw a simple spiral is impossible.
So, at the moment, they're just doing some baseline tests,
and as you can see, just how, you know, difficult it is for him.
How bad is that on a score of sort of one to ten?
Erm, it's probably ten.
It's pretty bad. Yeah. Yeah.
And how quickly do you think he will improve?
Fingers crossed.
Yeah, exactly. It's all about fingers crossed.
We'll know in the next half an hour or so
whether we've got a treatment here or not. OK.
If the beam strays even a fraction,
Thomas could end up with brain damage.
A half millimetre.
Move medial with a half millimetre move.
It takes huge skill and experience to get it right.
How far do we push this
before we start to cause
I mean, that's very, very impressive,
he was kind of doing that.
And it's still moving a little bit, but much better.
It's still a way to go.
'Thomas has already regained some control.'
Wow.
So, that is a remarkable progress, considering, you know,
a very short time ago...
he was only able to make sort of dabbing motions on there.
And now he's actually, you know, beginning to track the circle.
We're making some progress here. Would you agree? Yes.
'After five rounds of ultrasound, I can see a clear improvement.'
isn't he? Yeah.
This is probably one of
for a very long time -
the progression from that end to that end.
They weigh up whether doing more
could reduce Thomas's tremors even further.
But after his seventh blast, Thomas has a bad reaction.
MACHINE BEEPS
Everything stops while the team assesses what's happened.
'Still to come...'
Have you ever wondered
'I'll reveal the surprising science behind how we swallow.'
HE YELPS
'Every year, thousands of people in
What are the health benefits and what are the risks?
'And why exactly do our bones get weaker as we age?'
And that's what happens at breaks, you get micro microfractures.
Bones break at any age,
but after women go through the menopause or men turn 65,
we become
To find out more, I'm off to see Professor Sue Black
from the University of Oxford, who clearly loves her subject.
Hello. I am loving your collection. Thank you.
There's nothing not to love... About bones.
Once you start to study bones, it gets in your system.
So, isn't that just amazing?
It's not just the face, it's the opening into your gut system.
It's the opening into your respiratory system.
It's your visual system.
And then, of course, inside here, this is just a great big box
to protect the most delicate thing you can imagine,
which is the brain inside.
Yeah. It really does.
How many bones are there in the human body?
Oh, I have no idea.
And the reason I've no idea is because nobody agrees. OK.
So, some people will say there's 206,
some say there's 212 - unless you're a child.
And in a child, there are more than that
because bits of them haven't fused together yet.
'On the outside, a bone looks like it's completely solid.
But when we look at bone cells under a microscope,
it becomes clear just how alive it is.
Here, we can see cells whose job it is to build new bone.
So it's rather brilliant, isn't it? Oh, it's incredible.
I mean, it's an engineering, you know, miracle.
'Sadly, however, the miracle sometimes falls apart.'
Why, when we get older, do our bones get more brittle?
who get to a postmenopausal level,
and that's when osteoporosis kicks in.
Oestrogen as a hormone acts as a protector to bone.
'Osteoporosis affects one in five women and one in 20 men.
'But why? Sue shows me exactly what happens to your bones
'when you get osteoporosis.'
And you can see ends. You can see
And that's what happens at breaks.
Right. You get micro fractures.
And sometimes, they'll heal, and sometimes, they won't.
So, if you have more and more micro fractures,
you will get to a point where it's no longer a structure
that can withstand the forces that are going through it,
and then you get a catastrophic failure.
What can you do to prevent that?
then the amount of calcium that you take into your diet
is really important.
And we know that if you exercise regularly
and at an appropriate level,
Bones just continue to respond to
They do. They do.
'To prevent brittle bones, you need plenty of calcium, vitamin D,
'and weight-bearing exercises, like running or dancing.
They help to protect our delicate internal organs,
and they provide our bodies with structure and with shape.
It is impossible to imagine human life without them.
Weight-bearing exercises are a
but other forms of exercise, like having a swim,
also come with benefits.
Up on the Ayrshire coast,
they love a particularly bracing form of swimming.
"What am I doing? It's freezing."
This group are just some of the millions
who, every year, embrace cold water swimming.
Liberating. Absolutely liberating.
THEY CHEER
That's nature's magic. HE LAUGHS
Before they went in, our swimmers measured their skin temperature
using a thermal camera.
Red is hot, and blue is cold.
Their skin started off at around 22 degrees,
but after just 15 minutes immersed in the chilly Firth of Clyde,
our thermal camera reveals their skin temperature has dropped
to ten degrees - almost as low as the sea.
We hear a lot about cold water swimming,
but what actually goes on inside your body
when you go into cold water?
What are the health benefits, and what are the risks?
Back down south,
with the temperature still less than tropical,
physiologist professor Mike Tipton wants to put me to the test.
Hi, Mike. Nice to see you.
I feel a bit of a fraud, I must admit,
because I've got all this on at the moment.
It'll still work for you
OK. We don't mind people wearing wet suits,
if that's the way they're gonna start.
What I do is I go straight in. I assume that's probably all wrong.
Yeah. When you actually get to the point of going into the water,
you go in slowly because we want
MICHAEL GASPS Yeah.
Gasping and hyperventilation and a big workload on your heart.
You're a tropical animal.
You want to be in 28-degree air, doing not very much.
And you're taking that body and plunging it into 12-degree water.
It's a stress.
I think it's probably about time that I actually went in.
You gonna join me? No.
THEY LAUGH
MIKE CHUCKLES
your breathing under control
before you launch into anything.
Ooh-hoo-hoo-hoo!
It's when you do that. When it gets to the nether regions.
Whoo!
The hands are quite...
And that's because there's no blood flow there.
Look, if I just pinch your back of
The refill time is really long
because your body's shut down the blood flow to the extremities
to keep your brain and your heart
and your central critical organs warm.
Cos I feel quite a strong desire to urinate,
Yeah.
It's because you've shut down the blood flow to the skin.
All of that's gone centrally, increased central pressure,
and your body starts to try and off-load that fluid
by producing urine. OK.
But don't. LAUGHING: OK.
So, apart from wanting to have a wee,
what happens to our bodies when we swim in cold water?
Your arteries narrow,
so your heart suddenly has to work much harder pumping blood.
This is why cold water swimming isn't recommended
for anyone with a heart condition.
So that is a potential risk. But what are the benefits?
The cold also triggers the release of hormones,
which speed up your metabolic rate and may boost your mood.
I'm feeling fairly vigorous, must admit.
But a good thing is I've got a smile on my face.
I'm actually feeling quite, you know, cheerful about it. Yeah.
So, one of the big pluses that people always report is
for their mental health.
We've had the benefit of you being alert,
awakened, because that's the cold-shock response
just pouring stress hormones into the system.
The other thing we hear quite a lot about
is in terms of immune function. Yeah.
And so you'll have people saying,
"Since I've done open-water swimming,
"since I've done wild swimming, I haven't had a cold."
Jury's out on that.
There's not really been a very carefully controlled study. Yeah.
'But how long do you need?' Two or three minutes.
Get that cold-shock response, get
And then get out. And then get out.
If you are a novice, it's best to join a swimming group...
or try something more gentle, like a cold shower.
I wash in warm water, then switch to cold
and stand there for about 40 seconds.
Others prefer a dip in a chilly bath.
And speaking of chilly baths...
..have you ever wondered how much saliva or spit you produce?
Well, it's about one litre a day,
and that would be enough - over the course of three months -
to fill a bath this size.
And in fact, over a lifetime,
you would be able to fill around 320 bathfuls.
So, why do we need to produce so much saliva?
Well, amongst other things,
producing saliva helps us to swallow -
something we do as much as 500 times a day.
I've agreed to have a camera put somewhere uncomfortable
to get a proper look at how it all works.
I'm in the capable hands of consultant Suzanne Slade.
Hi. Good to see you. Hi. Come on in.
Thank you. Come and have a seat.
Gonna have a peer down my throat, are you?
And... don't worry.
through your nose.
There's a camera on the end here?
So, it's going to light everything up on the inside.
HE GROANS, SUZANNE CHUCKLES
Right, so... Here we go. OK. I'm gonna be brave.
Just breathing in and out.
So, we're just heading along the floor of the nose now.
We're gonna be very, very gentle. Ooh, that's weird.
We're almost there. SQUELCHING
down into your voice box.
Ahh. Absolutely fantastic.
then we see the vocal cords tapping together.
Hee-hee-hee-hee.
So, this is really the opening to both my breathing
and also to my food, if you like.
You want to eat and drink,
to go down into your lungs.
Absolutely. So, in the centre of your throat here,
we're seeing the entrance to the lungs.
If you were to... This is a bit crude, but if you were to belch,
we might actually see the... Yeah.
Oh, there we go.
The opening of your food pipe.
Are you happy to take a bite of banana? Yeah.
So... And we can see... see the base of the tongue,
which is at the bottom of the screen. Mm-hm.
And that's you just chewing, getting that banana ready.
and then - boop - it's gone.
There's a little structure called the epiglottis,
and that flips back and almost puts a lid
on the entrance to your windpipe.
'Your epiglottis flips back and forth every time you swallow.
'This tiny flap of cartilage allows you to safely swallow
'and breathe without having to think about it.'
If you had a swallowing problem,
if you'd had a stroke or something like that,
then dealing with the saliva can be a huge issue.
If you're not swallowing,
then it can just trickle down into the larynx
and then into your lungs.
Very fine balancing act, isn't it? It absolutely is.
I think I need to have it out now. SLURPING
Ah!
Oh. Well done. Well done.
Huge amount of snot.
Thank you for this. I probably need more.
SUZANNE CHUCKLES
Swallowing is a complex process.
Under direction from your brain,
your throat muscles must all work together -
which is why swallowing can sometimes be affected
by problems with your nervous system.
Back in Dundee, the operation to treat Thomas's essential tremor,
caused by malfunctioning circuits in his brain and nervous system,
has reached a critical point.
It was going really, really well,
and they were hoping to push it further.
But in the moment, Tom is being violently sick in there.
Everyone's kind of gathered.
'Before that happened, the team managed to successfully bombard
'a tiny area in his brain with ultrasound waves,
'and the impact of that on his tremor has been dramatic.'
You pleased?
Oh, it's... it's amazing.
It's stressful, but you're so pleased.
I'm just shaking from the... MICHAEL CHUCKLES
..the experience.
I'm so grateful to everybody.
Amazingly, later that afternoon, Thomas is up and about.
'I noticed a change right away.'
It's improved far, far more than I thought it would.
a life-changing difference.
I haven't been able to drink with my right hand for years.
Previously, that would have been down my chin and onto my jersey.
And that is no problem at all now.
I would say.
What I've seen today is absolutely astonishing.
and, by doing that, give Tom his life back
is absolutely mind-boggling.
'Coming up...
'What causes deadly blood clots to form in your heart?'
Your heart is a wonderful organ.
The electrical system
until it goes wrong.
'I take a test to see if I'm at risk of having a stroke
'in a most unlikely location.'
Nervous at all?
Yes.
'And you have enough blood vessels in your body
'to stretch from Land's End to John O'Groats - true or false?
Right. That's my heart, yeah? This is your heart...
'Seeing the fatty plaques in my coronary arteries,
'the vessels that supply blood to my heart,
'hammered home just how important it is to protect those arteries.
'But coronary arteries are just one part
'of a vast circulatory system.'
If you were to take all
how far do you think they would stretch?
Once around the track? Twice?
No. The average human body contains 60,000 miles of blood vessels,
or about 240,000 times round this track.
That is like travelling from Land's End to John O'Groats
more than 70 times.
And if any of those major blood vessels
gets damaged, you could have a stroke.
To find out more,
If you could be inside your heart when it pumps,
it would feel something like this.
Every second of every day,
your heart beats away to its own rhythm.
And as you speed up - or indeed, slow down -
your heart does likewise without you having to think about it.
Those changes are driven
by a small cluster of specialised cells
which send electrical signals
to the different chambers of your heart,
making them beat in a coordinated way.
But sometimes, the signalling becomes faulty.
If the heart starts to beat erratically,
then it's known as arrhythmia.
is atrial fibrillation,
otherwise known as AF.
Now, this is a serious condition, and it needs to be detected early.
If your heart isn't pumping as it should,
blood can hang around inside the heart too long,
and dangerous clots form.
If a clot breaks off, travels to the brain and blocks blood flow,
that can cause a stroke.
Here in Liverpool, they're working on a novel way
to detect those dangerous arrhythmias
and prevent strokes.
I'm off to try it out with the help from some of the locals.
Hello, everyone. ALL: Hello.
So, you're all here to see how good your hearts are.
'Just how common is atrial fibrillation?
Professor Ian Jones is an expert in cardiology.
The incidence of AF is only 1.5%, roughly, in the population.
As you get older, it increases,
so the older population would be more likely to pick that up.
'Ian and his team have come up with a novel way
'to detect undiagnosed atrial fibrillation.
'Enter the humble shopping trolley.
'But these are no ordinary shopping trolleys.
'Hidden in their handles is a simple yet powerful bit of tech.'
So, the sensor inside the middle of the handle is an ECG sensor,
so it will measure the person's heartbeat,
their heart rhythm, over a period of one minute.
it will record it.
So, just push the trolley around as you would do normally.
Nervous at all? Yes.
LAUGHTER
'Will the trolleys detect dodgy heartbeats in our group
'or in me?'
So, the way this works is I'm just strolling around,
but I'm also gripping this metal handle.
And what it's doing is essentially measuring
'Lights on the trolley turn red if you have an abnormal heartbeat.'
I'm hoping it's gonna be green.
And there it goes.
They're coming round now.
Be interesting to see whose light is flashing what.
Hey. Hi, there. Hello.
OK, so you are green. Wahey. Well done.
So, are you green as well? I am.
Marvellous. Hi. Hello.
Right, so, what do we see? Green. OK. Coming by.
I am green. You are green. Marvellous.
'Ian has already conducted a study involving over 2,000 people
'which found 59 new cases of unsuspected cardiac arrhythmia,
'suggesting this ingenious idea really could save lives.'
Do you think it's a good idea, bad idea? Is it a bit invasive?
I think it's brilliant.
It's not taking any time out of your day
that you wouldn't be spending anyway.
Also, what we're talking about preventing here is strokes. Yeah.
And strokes are devastating conditions.
I always think you're only one blood clot away
from a life-changing event. Good motto.
As well as atrial fibrillation,
another very common cause of stroke is having high blood pressure.
So, if you haven't had it done recently, do get yourself tested.
Your heart is a wonderful organ.
The electrical system which drives it
is also remarkable - until it goes wrong.
Then you're probably gonna be grateful to people like Ian,
who are devising ingenious ways to detect it,
and others who are finding better ways to treat it.
'And here's another surprising way to protect your heart -
'brush and floss.
'Bacteria in the mouth that cause gum disease have been linked
'to an increased risk of heart problems.
'So to help your heart, take care of your teeth.'
There's still so much more to discover
Plus the head of her femur.
Next time...
One in ten of us will need a new hip at some point.
We film a fascinating hip replacement operation.
Was she in a lot of pain? Agony.
People often complain about stress, but it can be a good thing.
To explore what stress really does to your body,
I go way out of my comfort zone.
I am feeling sort of panic.
and I reveal three things you at home can do
to reduce your blood pressure without needing to join a gym.
This is a real thigh-burner.
Okay.
One of Michael's greatest passions
has always been to reveal the extraordinary secrets
of how our bodies work.
MAN: Brilliant. Thank you. MICHAEL: Yeah, that's good.
He spent several months with the production team...
OK, yeah, a couple more.
..travelling far and wide for this brand-new series on the human body.
Just look.
The family and I are delighted to introduce it to you.
You sit down there.
'Michael even persuaded me to participate...'
LAUGHTER
'..tipping him upside down...' Blimey.
LAUGHTER
'..as well as filling his ice bath...'
Go for it. Great. '..all in the name of science.'
And I'm sure he would have enjoyed the programme.
HE LAUGHS
We're heading off on an extraordinary journey
around the human body.
And if you give us a little chuckle...
HE CHUCKLES
Have you ever wondered why we get creaky joints?
Does your body hold the power to stop cancer from multiplying?
How do you remember to breathe?
'I'll be tracking down answers to lots of burning questions.'
HE EXCLAIMS
I feel quite a strong desire to urinate.
But don't. LAUGHING: OK.
'From what exactly is in our farts...'
So, this device, which we colloquially refer to
as the thunder funnel... That's great.
'..to how long we take to digest our food...'
Are you wearing it overnight? Absolutely.
'..I'll show you how we can all live healthier, longer lives.'
This is one of the most impressive things I've seen
for a very long time.
'And I put my body to the test...' Hey!
'..to help you at home understand yours.'
STRAINED: I'm stuck. Get ready to see yourself...
Ooh! ..in a whole new light.
This time, we go behind the scenes at Britain's biggest blood factory
to find out why blood is such a wonder of the human body.
There's about 26 trillion red cells in your body. Oh, wow.
At this factory, they work 24/7
to ensure that if you ever have to have a transfusion,
you get the blood you need.
I'll find out how we can reduce our blood pressure
without needing stretchy exercise wear
or joining an expensive gym.
This is a real thigh-burner.
Plus, a bodily function we all do as many as 15 times a day.
HE FARTS
But what is it about breaking wind
that makes you feel you need to blame the dog?
Wonders Of The Human Body tackles the burning questions
that you might have about your own body.
I'm starting out by looking for answers to a silent killer
which is incredibly common but often missed.
I'm talking about high blood pressure.
Your heart is there to drive blood around your body.
This powerful muscle pumps away,
and blood pressure is the force of the blood
pushing against the walls of the vessels.
Your blood pressure is a measure of the pressure on your arteries
when your heart contracts and when it relaxes.
That's why it's two numbers.
The pressure is highest when your heart is contracting
and lowest when it's relaxing.
Everyone is different,
but a healthy blood pressure should be less than 120/80.
More than half of Brits over 65 have unhealthy blood pressure.
To illustrate what's going wrong,
I'm going to need a really big pump.
Well, imagine this hose over here is an artery,
and the engine over there is the heart.
Now the heart is working to pump blood through this hose
to the hungry organs of the body...
OK, lads, keep going.
..which is fine if your arteries are nice and supple.
The trouble is that as we get older,
these arteries tend to become stiffer and narrower,
and that means that you need even more pressure...
..so your heart has to pump harder.
All that extra pressure puts strain on the heart,
and it also damages the lining of the arteries.
Even if you feel fine,
it is important that you get your blood pressure checked regularly,
especially if you're over 50.
High blood pressure is known as the silent killer
because it often comes without symptoms,
and unless you've got a machine like this,
you're not going to know you have it
until perhaps you have a heart attack or stroke.
I feel particularly strongly about this
because I have several close friends
who've died as a result of untreated high blood pressure.
Luckily, there's simple exercises you can do at home
which can reduce blood pressure.
OK, so, this is the plank.
The idea is you go up on your elbows,
keep your body straight and hold this for as long as you can,
ideally for up to two minutes, which, I can assure you,
is a long time if you're doing the plank.
Isometric exercises where you tighten your muscles
but don't actually move them, like the plank or the wall sit,
can help reduce blood pressure in the comfort of your own home.
So, this is the wall.
You put your legs out about 2ft,
and this is a real thigh-burner.
Well, maybe "comfort" was the wrong word.
The idea is you try and hold it for about 20 to 30 seconds,
you have a breather and you go and do it again another couple of times.
Now, this is a surprising one, and it's particularly suitable
if you can't do more conventional exercise.
Now, what you have to do is you have to grip this thing,
and the idea is you squeeze it,
and then you hold it for a couple of minutes,
and you do it again a couple more times.
And you try and do this about three times a week.
You can get hold of these grip strengtheners
pretty easily online.
So, how exactly do these sorts of exercises
help reduce blood pressure?
Inside your muscles, you have a network of blood vessels.
When you hold an exercise pose,
the muscles squeeze your blood vessels.
Then when you stop squeezing,
the sudden rush of blood expands your vessels again.
Repeating this on a regular basis
makes your blood vessels more supple,
and because they are now more supple,
this helps lower your blood pressure.
It really is impressive,
the way that these relatively simple exercises
can bring your blood pressure down.
And it also shows how remarkable your body is
that it can self-repair if you give it the chance.
Don't panic if you get an occasional high reading.
Many things affect blood pressure, such as poor sleep or stress.
And as well as helping lower blood pressure,
daily exercise is also very good for your joints.
Every hop, skip or jump I have made or will ever make
is thanks to my hips.
I want to find out more about these remarkable bones.
Our hips start out strong and mobile,
but the sad fact is that one in ten of us
will eventually need hip replacement surgery,
so can we reverse our hip destiny?
To keep working efficiently, our hip joints rely on
the most slippery natural substance ever discovered.
HE CHUCKLES
Not ice - but cartilage.
Cartilage is amazingly flexible and also acts as a shock absorber.
It doesn't have a nerve supply,
so it's ideal for wherever two bones meet,
preventing them rubbing against each other.
This ice is very slippery, which is why I'm walking with caution,
but cartilage is actually five times more slippery than ice.
Super slippy cartilage
plus a watery lubricant made by your blood
helps your joints move with ease.
But we certainly notice when it goes wrong.
In Middlesex, there's someone who knows all too well
the agony that hip problems can bring.
It's just constant pain throughout the day. Er...
Getting in and out of the car is difficult.
Just doing housework, gardening, er, can be extremely difficult.
43-year-old Claire Hayward
has been admitted for an urgent hip replacement.
She has osteoarthritis,
a condition where the cartilage in her hip joint
has largely disintegrated,
leaving the bones to rub against each other and wear away.
Consultant's just told me this morning,
it looks like my left hip is about to collapse
because the bone has worn away that much.
It's osteoarthritis.
I've had trouble throughout my whole life with my hips.
Today, I'm feeling a little bit overwhelmed.
Feeling quite emotional
because I'm looking forward to actually being pain-free.
And I worry about my kids. I just worry, you know.
Hopefully, I'm gonna be OK, there's no complications
and I can get home within the next couple of days.
Osteoarthritis can be inherited or the result of injury or overuse.
Once the cartilage has disintegrated,
your best bet is a new hip.
And a pair of eight gloves for me, please.
At the Royal National Orthopaedic Hospital in Stanmore,
they are hoping a new kind of hip surgery pioneered here
will help change Claire's life.
I am looking forward to this.
It's been a long time since I've seen an orthopaedic operation,
and I imagine it has changed a great deal in that time.
Just pull it down at the front.
Coming up...
An extraordinary ability most of us have no idea we possess.
I get to the bottom of what's really in our farts.
Now, farting may not sound like one of the wonders of the human body,
but it is a fascinating subject
and one I'm going to explore further
with the help of this portable gas monitor.
And blood. What exactly is in it?
So, there you go. A lovely drop of fresh blood.
I'm not normally a heavy drinker, but for the sake of this programme,
I thought I would pop into a local pub.
Afternoon. Brilliant.
Could I get a pint of your best, please?
Lovely.
And could I get another pint, please?
Fantastic. Thank you.
And could I get another pint, please?
Could I get another pint?
And I would like one more pint, please.
Have you ever wondered how much blood there is in the human body?
Well, it comes to around 5l,
which is about nine pints.
Many of us give blood just under a pint at a time,
but what's in blood that makes it
such a precious and life-saving liquid?
We're heading to Bristol
and one of the biggest blood processing plants in the world.
A regular blood donor, Meshach Snape,
has already given an impressive 30 pints.
My older sister was always donating blood.
So from seeing her doing it all the time,
she encouraged me to start doing it,
and from then, I haven't looked back.
And today, he's getting inside the factory
to find out first-hand what happens to the blood we donate.
It's almost like... like you're in Charlie And The Chocolate Factory.
Obviously, there's nothing you can eat.
It's just amazing.
Blood doctor Liz is leading his tour.
An amazing, amazing facility, this is. Yeah.
So, all the blood from Midlands and the South West
comes into this unit. Yeah.
So your donation will come into this unit to be processed. Yeah.
Once the precious donated blood arrives,
it is carefully separated out
into different component parts by machines.
As you might expect,
almost half of your blood is made up of red blood cells,
essential for delivering oxygen everywhere our body's needed.
The rest is plasma,
a fluid that is crucial for health and longevity.
As well as carrying white cells that fight infection and disease,
your plasma transports platelets
that are essential for blood clotting.
Plasma is great because we can make it into a product
we give to people who are bleeding.
It can help stop them bleeding. OK.
It also contains antibodies,
and that can be used for people who don't have a good immune system
and can help them fight infections.
OK.
This place is impressive, but so is the fact that your body
can churn out new blood cells at an extraordinary rate.
And you're making between
two and three million red cells a second.
That's why you can donate blood and your body kind of...
Replenishes it. ..replenishes it and makes more.
Every precious donation helps places like this one
do their life-saving work.
All those different parts means that we can save up to three lives
with each donation.
OK.
I want to give blood until... until I can't no more.
I'm just gonna carry on giving blood,
hopefully encourage others to give blood.
'There's no other pint quite like it. Cheers.
'Back in Stanmore, 43-year-old Claire is hoping to have
'her life transformed later today.
'Leading the surgical team at the Royal National Orthopaedic Hospital
'is Professor Alistair Hart.'
So, can you tell me about Claire?
She is a young lady, considering the average age of patients
that we give hip replacement to.
In the UK, the average age is about 67.
'Alistair shows me what can happen when hip joints
'like Claire's lose their protective coating of cartilage.'
Here. This is what can go wrong. Slightly more unusual.
So, in this hip...
SQUEAKS
..the cartilage has worn off,
and you've got bone rubbing against bone.
Right. That's what's causing squeaking.
Ooh! Wow. Was she in a lot of pain?
Agony. Yeah.
To save her from further pain and disability,
Alastair will remove the damaged head of Claire's thighbone
and fit an artificial implant.
It's proved extremely hard to mimic a human hip
because it's such an extraordinary bit of biological engineering.
So, second patient, Claire. Are you happy?
Good. Thanks a lot.
Most artificial hips fail after 25 years.
Often because it's so very hard
to achieve a design and fit that's precise.
That'll need to come up a little bit.
'Amongst other things, Alastair and the team use
'a plastic 3D-printed model which helps him decide
'exactly where to cut Claire's bone.
'Positioning her new hip implant precisely
'should ensure it lasts longer.'
And we're now going into the hip joint itself, into the capsule.
So step one will be the removal of the head of the femur, will it?
Yes.
'Alastair shows me the plastic model he's made
'of Claire's existing thigh bone.'
These are unique to this lady.
OK. That's the top of her thigh bone, femur.
OK. It's really knackered, isn't it? Yeah, it's very distorted.
These are unique...
and this piece fits very nicely...
OK. ..showing us exactly where to make the cut.
OK. And the previous method generally involves
an orthopaedic surgeon using their finger.
Yes. And very approximate.
And you've got to be right within degrees, this one.
Wow.
These can come out.
What those 3D models allow him to do is to align the bits up perfectly,
and that means that there's much less chance that this hip will fail.
So, this is the moment of truth. Right. Yep.
So... That's the 3D model.
Will this guide actually fit onto the patient's?
Yep. OK.
'If this doesn't work, and the artificial hip fails,
'Claire will be in terrible pain all over again.'
The next stopping point on our journey around our bodies
is truly eye-opening.
The human eye is another wonderful example of biological engineering.
Sight is so important to us
that more than half the surface of our brains,
the cortex, is dedicated to processing visual information.
But even if we are without vision,
we can still draw on a hidden superpower.
Anybody who loses vision in the way that I did,
very suddenly and very quickly, is it's incredibly difficult.
Jayne Hyde-Dryden lost her sight
in her 40s after she developed a condition called glaucoma,
which caused damage to her optic nerves.
I remember sitting in my living room,
not really being able to move around my house properly,
not being able to stand up from the chair and move to the door.
And I just felt very, very alone in this... in this dark world.
Jane is now totally blind,
but her world has been opened up by a startling new skill,
something we usually associate with bats or dolphins.
Echolocation.
CLICKING
Echolocation has absolutely transformed my life.
It basically involves the tongue hitting the roof of the mouth.
CLICKING
The sound travels to the object and back to my ears.
If an echo comes back quickly, the object is close.
If it takes longer, the object is further away.
And then what happens is something magical in the brain happens
where the sound is transferred into an image.
I use echolocation every single day.
The idea you can be trained to see using sound
is extraordinary, but Jayne's living proof.
I sense things throughout my entire body when I'm walking around,
which sounds a bit odd and a bit weird.
But I can determine if something is hard or if it's soft,
how high it is.
I can see different textures.
PEDESTRIAN CROSSING BEEPS, BELL TOLLS
I tend to take real note of my environment.
Jayne was taught how to echolocate
by Doctor Lore Thaler at Durham University.
Amazingly, apparently anyone can do it if they learn how.
So, we have an object in front of you.
It's a plank shape, so it can be vertically
or it could be horizontal.
So your task is to echolocate it
and then tell us which orientation it is.
All right.
CLICKING
That's right. Horizontal. Yeah.
After five years of training,
Jayne now gets it right about nine out of ten times.
When I echolocate with something,
am I using the same, similar part of the brain
to someone who's looking at something?
Yes, that seems to be.
Yeah. That is just so cool, isn't it?
Yeah.
Laura has shown that as well as the visually impaired,
sighted people can also learn to echolocate
if they practise hard enough.
What was amazing also that the people who are blind got better,
but also the people who were sighted,
everyone got better.
I think it's just so cool that everyone has the ability
to learn this technique.
CLICKING
And actually, everyone does echolocation naturally,
I would suspect.
So there will have been times, I'm sure,
when people have gone to the toilet in the middle of the night
and they have stopped
because they know they're going to walk into the door frame.
That is your in-built passive echolocation working overtime.
For me, I'm really proud to be able to just move with freedom.
For all of us, sighted or not,
the world can at times feel like it's designed to stress us out.
And long-term chronic stress has been blamed
for a host of serious conditions,
from heart disease to depression and even Alzheimer's.
But being stressed is not always a bad thing.
'To help explore our body's response to stress
'and find out what we can do about it...'
I felt a little frisson of fear there.
'..I put myself in a very unnatural situation.'
I'm halfway up a crag.
There's quite a long way down, but there's an awful long way up,
and this is the hard bit.
The classical fight-or-flight response is of such interest to us
because from an evolutionary perspective,
it's perhaps what allows us as a species to have survived,
but we also experience it every day.
You go into an interview or an exam or you have stress at work.
It's the same response. It's a stress response.
'Coming up... I find out what stress is and how to overcome it,
'if I can summon up enough courage to keep climbing.
'Talk about a cliff-hanger.
'Plus...' EXCLAIMS
'..I explore the extraordinary science
'behind how we get around on two feet.'
Woo-hoo!
It is incredibly windy in here.
That is appropriate because I'm about to introduce you
to one of the wonders of the human body that we don't often talk about.
'Did you know that women may fart more than men?'
Thank you very much. Over and done. You won.
That's the head of her femur.
'And will a new approach to hip replacement surgery
'give Claire her life back?'
MICHAEL MOSLEY: 'We're in Snowdonia, where I'm on a mission
'to learn more about what stress does to our bodies.
'To do that, I'm putting myself through a very stressful experience,
'almost 100m up.'
God! HE LAUGHS
Sorry, that's my hands. Yeah, cold.
You all right?
'30 minutes earlier, I was rigged with a heart rate monitor
'by Jamie Macdonald,
'who is professor of sport and exercise science
'at Bangor University.'
What it allows us to do
is just get a visual picture of what's happening to you
as you respond to this fight-or-flight response. OK.
'I'm expecting the monitor will show I am way outside my comfort zone,
'unlike Jamie's colleague, Professor Tim Woodman,
'who's an experienced climber.'
There you go. I think he's doing very well.
Well, he's obviously a little bit anxious.
It's interesting. I'm definitely feeling uncomfortable now.
So, the green line here is Michael's heart rate response.
And the orange line is Tim, who's climbing right next to him.
And that really does look quite vertical, doesn't it?
It's starting to get a bit more steep, isn't it? Yeah.
And what's interesting here
is that they're doing the same amount of physical work,
yet Michael's response is much greater.
'I do exercise regularly, but the amount my heart is racing
'is a clear sign of my stress response in action.'
Jesus!
OK. Blimey.
Well done.
So, now Michael's overcome that initial anxiety,
he needs to continue to be ready for activity.
Oh. That's it.
There's this amazing hormone called cortisol,
and cortisol is known as the stress hormone.
So, the cortisol will keep his heart rate high.
It will trigger his blood flow to different parts of the body,
the muscles, the brain.
And we're going to monitor that later
when we measure the cortisol in his saliva.
I've got my cortisol swab here, and I'm just going to feel my mouth.
Can you time me? Timing you for two minutes, starting now.
Two minutes, yeah.
OK, that's it for the... OK.
OK, it'll be interesting to see what the result of that is.
I'd be astonished if I'm not a bit stressed.
Most of us have heard of the stress hormone cortisol,
but how exactly does it work?
When you're stressed, your brain sends a signal
to glands near your kidneys, telling them to release cortisol
into your bloodstream.
That's normal.
But if levels rise and stay high, that can be bad news.
Too much exposure to cortisol can disrupt the body's normal processes.
And that, in turn, can increase your risk
of serious health problems, such as high blood pressure and diabetes.
Coming up. Oh, a bit...
So, I am feeling sort of panic.
But I overcome my fear and make it to the top,
and the view was well worth it.
I'm no mountain goat, that's for sure.
With my ordeal finally over,
it's time to regroup with Jamie at the bottom.
Hi there. Oh, blimey, that was hard.
The test reveals that my cortisol was a whopping three times
the expected level, and the effects can hang around for a few hours,
so I'll probably have elevated blood pressure
even after my heart rate comes down.
But the odd thing is, I also quite enjoyed it.
I have to say, from a just purely personal point of view,
feeling half way up,
never, ever, ever want to do this again.
By the top, I was thinking,
"Actually, yeah, I could do this again."
HE LAUGHS That's great.
A short, stressful challenge like mountain climbing
can give us a feel-good buzz,
but chronic stress is really bad for us.
Fortunately, there are some easy things you can do
to manage chronic stress and help improve your health and longevity.
Having a good laugh will reduce cortisol levels.
Getting active and also practising deep breathing is especially good
for calming your nervous system.
And a dose of fresh air, preferably somewhere green,
is always good for stress.
In Stanmore, mum-of-two Claire, has been admitted
for what she hopes will be life-changing surgery.
A leading orthopaedic surgeon, Alastair Hart,
is at the critical stage of the operation.
So this is the moment of truth. Right, yep.
'Earlier, he made a plastic model designed to test how well
'the real hip implant will fit when he puts it into Claire's body.'
So, let's see.
It's very like, erm, Lego.
And that fits very nicely to me.
Yeah. It looks beautiful. It looks... That's very solid.
'The plastic template can now be put aside.
'It has done its job, showing Alistair
'exactly where he needs to cut through bone.'
So that shows you exactly where you got to cut.
Make the cut. Here we go.
DRILLING
So you just cut through the bone?
So it's got absolutely no cartilage here at all.
So this should be nice and soft.
And it's rock hard. Yeah.
And she's been walking on that and is a very painful joint. Yeah.
'Claire's new custom-built artificial hip
'is now ready to be fitted.'
So that's a short, right?
'And just over an hour after starting,
'Claire's new hip is in place.'
So that's her new hip articulation. Brilliant.
And within a day or two, she's going to be up and about.
She'll be walking tomorrow morning, yeah.
Maybe later this evening, if she's keen. Yeah.
Right. I think the operation is done.
'Only time will tell if Claire's new hip will be a success.'
Good day's work. Yes. I've changed my shirt.
If you experience discomfort in your hips or your lower back,
it could be down to how you walk.
No-one really knows why humans first started walking upright,
but with an erect posture came back problems.
Here at the Edinburgh Centre for robotics,
they're studying exactly how we manage to get around on two feet,
with the long-term goal of helping those who can't.
And they are doing this
with the help of some very unusual lab assistants.
Ooh, very good.
It reminds me of teaching my children to walk.
Basically, you have to grab them just as they're about to keel over.
Whoa! There we go.
Professor Sethu Vijayakumar is leading the team,
and today, I'm his guinea pig.
We're gonna try running some walking tests on you.
We don't normally think that much about how we walk, we just do it,
so I'll be intrigued to see what the researchers make of my walking.
OK. What do you think? You're looking good.
Looking good? Thank you very much. OK.
On the treadmill, cameras track sensors
which are attached to my body to record my exact movements.
We actually can see you in real time on the screen.
The skeleton of you walking.
When humans walk, we tend to walk by falling forward.
Yeah, OK.
If you look carefully, you can see I'm always off-balance,
slightly tipping forward.
But what's amazing is my body constantly senses
the ground beneath me, allowing me to respond to changing terrain...
EXCLAIMS
..without needing to think about it.
I did not expect it to do that.
So how does your body manage to react so well to surprise?
Whoo!
Now, I was able to correct myself almost immediately on that.
You get an unexpected event, like a push,
then your automatic part kicks in
where it prevents you from falling over.
The secret to this lies in something called your reflex arc.
When your legs start to stumble, nerve signals travel
to your spinal cord, and messages then go straight back to your legs,
telling them how to correct your balance.
For the sake of speed,
your reflexes actually bypass your brain.
'Walking, of course, is very good for us.'
If everyone did at least 15 minutes a day,
as many as one in ten premature deaths could be prevented.
EXCLAIMS
Our bodies have evolved to walk upright,
helped by large muscles in the bum,
the aptly named gluteus maximus,
by our Achilles tendons, and even by the arches in our feet.
Of course, cardio workouts that you can do sitting down
will also provide health benefits.
Whoa! Weird.
Sethu also wants to use the research being done here
to help people regain mobility.
This is a small step for me but a giant step for mankind.
Hey, I love the noise. I have to say.
MECHANICAL WHIR
This is an exoskeleton, a wearable robot.
So just gently.
HE LAUGHS
That is very weird.
There's part of me which is quite confident that I can probably...
Da-da-da!
I can't dance, but I can absolutely move. Turn. Yeah.
The exoskeleton can support itself.
And let's say you are somebody with a disability
and you didn't have the force to actually move your legs,
then this exoskeleton could kick in at that point
and assist you such that you feel like you're walking normally.
For many people, that would be a big thing.
Absolutely. Absolutely.
OK, I'm feeling confident. Yeah.
For people who've had an injury,
a stroke, or a condition like Parkinson's,
exoskeletons like this one could one day support them
as they learn to walk again.
How long do you think before people
are gonna start wearing these in a more routine way?
I think it's going to be at least five to ten years.
'That's a long time to wait.
'But in the meantime, I can promise you they're a lot of fun.'
No. It's cool.
So now I know what it feels like to be a cyborg.
Time to move on from something incredibly high tech
to something that's far more down to Earth.
Ooh!
It is incredibly windy in here.
That is appropriate, because I'm about to introduce you
to one of the wonders of the human body
that we don't often talk about...
and that is breaking wind.
So, what is it that happens when we fart?
And what is in those farts?
Whoo!
At least this is an experiment that I can do at home.
'I'm trying to produce a fart to see what's in it.'
Nope.
While we wait, here are some fabulous farty facts.
So, on average, we produce up to a litre of gas a day.
And then, of course, we release it. We know these numbers
because scientists have studied this serious subject
by putting tubes up people's rectums.
Studies have also shown that the average person farts
up to 15 times a day, which, over a year, really adds up.
Now, this is about 300 litres of gas,
which is roughly the amount you produce every year.
Chances are, you or someone uncomfortably close to you
is likely to break wind at least once
before the end of this programme.
DOG WHINES
FARTS
Coming up, has Claire's pioneering hip surgery been a success,
and will she soon be pain-free for the first time in years?
I'll reveal the different gases that make up your farts.
You have some methane, so you're one of the lucky ones
that have some methane. Woo-hoo!
And just how flammable are farts?
I urge you, do not try this at home.
MICHAEL MOSLEY: Our journey round the human body
has taken us from the top to the bottom.
I've come to Loughborough University to meet Professor Jim Reynolds.
Jim has kindly offered to use his considerable scientific expertise
to capture and test my farts.
Hi, Jim.
Ah, morning, Michael.
Now, I gather you've been putting something together to help collect
and analyse my farts, yep?
That's correct, Michael.
So, this device, which we colloquially refer to
as the Thunder Funnel... Ha-ha, that's great! OK.
Yeah. You might not want to sniff that.
LAUGHS
So, this is a small pump.
This will extract the gas,
and it will measure how much gas is released.
OK. Have you done this yourself? No comment.
LAUGHS
OK, so, I'm assuming what happens
is you just kind of lift that end, will you?
That's correct. Place it there.
Yeah. We switch the pump on and then open the valve.
And there we go. Brilliant. Fart in a bag.
With the Thunder Funnel in place, it's now just a waiting game.
FARTS
There she blows!
Woo-hoo! Result!
Now that my wind's been captured,
the team will analyse exactly what is in it.
Which for me, at least, is quite exciting.
Chemist Mickella Dawkins will do the analysis.
I have an offering for you.
Thank you very much. That's quite a lot.
So, what are you expecting to find?
So, I'm going to find out what's in your farts.
And we're gonna use this machine,
which is called a gas chromatographer.
It separates out the gases
and tells me what's in your fart, basically.
It's results time, that was fast. Yeah.
SHE LAUGHS
Fantastic. So, let's it bring up here.
So, this is you. So, this is me.
Yeah. So, first of all, most of it, as you can see, is air.
So we have quite a lot of nitrogen
and also carbon dioxide, which we find in the air around us.
'Most of the gas we release through our bottoms
'is just air we swallowed earlier.'
But it's not all hot air.
Around 100 trillion bacteria live in your intestine.
They help to break down food and release gas while they do it.
The gut bacteria are obviously doing something.
Yes, which is why we have the hydrogen coming through,
which we find in everybody's farts.
The thing which produces a lot of the smell. Yes.
And which we are incredibly sensitive to... Definitely.
..is hydrogen sulphide. Yes.
And where would you normally encounter it in the real world?
So, rotten food.
Ah, OK, so, really, what it's measuring is rot, decay,
something which is dangerous, and that's why it's so important to us.
We can test for it.
So we can use something called lead acetate paper
and squeeze your gases over it.
Marvellous.
It should go brown, browny-black colour if there is enough in there.
Yeah. OK.
So the moment of truth, are my farts smelly?
Not at all brown. Not at all brown. So good news.
Instant woo-hoo! Hey!
I may be producing farts, but they're not smelly.
LAUGHS
Have you analysed yours? No. Not yet.
Not yet. Brilliant.
So there you have it.
Many of the gases coming out of your rear end...
FARTS
..come from air you've swallowed earlier.
Your gut bacteria make hydrogen and pong-y hydrogen sulphide.
But for most people, it's there in such tiny quantities,
it barely registers.
Despite the fact your nose is super-sharp
at picking up every last drop of it.
And there's another gas that some of us produce. Methane.
I've just captured some methane gas inside these soapy bubbles.
Let's see what happens when I light it.
Whoa! That was magical.
Now, as you can see, methane is incredibly flammable.
It is a gas produced in your gut, and not all of us do so.
In fact, only around one in four people produce methane.
And obviously, some people on the internet
are busy trying to light their farts.
I would strongly recommend you don't do that.
Whether or not you produce methane is down to your genes, your diet,
and your own individual mix of gut bacteria.
When I first started looking into the subject of farts,
I had no idea it was going to be quite as interesting as it is.
But on the whole, the fact that we fart, well,
that is just entirely human and nothing to be ashamed about.
Remember Claire, who we followed having a pioneering hip replacement?
Here she is ten weeks later.
There's no pain. I used to get pain doing this machine,
but now, it feels great.
Here's hoping that the cutting-edge surgical techniques we saw earlier
will keep her and others like her
pain-free and mobile for decades to come.
The human body is full of surprises,
and what's exciting is there is so much more to learn.
How do you remember to breathe?
INHALES
STEADY BEEPING
Respiratory diseases are one of the main causes of death in the UK.
We follow the extraordinary story of Clifford,
who is undergoing pioneering lung surgery.
I don't know what to expect.
SHOOTING
Wahey! One down, a billion to go.
How exactly does your body react to invading viruses like the flu?
And the last drop now.
And I reveal three things you can do to keep your brain
in peak condition as you age.
Whoa!
Okay.
'One of Michael's greatest passions has always been
'to reveal the extraordinary secrets of how our bodies work.'
Brilliant. Thank you.
MAN: Yeah. That's good.
'He spent several months with a production team...'
OK, yeah, a couple more.
'..travelling far and wide for this brand new series on the human body.'
Just look.
'The family and I are delighted to introduce it to you.'
What I want you to do is sit down there.
'Michael even persuaded me to participate...'
THEY LAUGH '..tipping him upside down...'
Blimey! THEY LAUGH
'..as well as filling his ice bath...'
Go for it. '..all in the name of science.'
Great.
'And I'm sure he would have enjoyed the programme.'
HE LAUGHS
We're heading off on an extraordinary journey
around the human body.
And if you give us a little chuckle...
HE CHUCKLES
'Have you ever wondered why we get creaky joints?'
CREAKS
'Does your body hold the power to stop cancer from multiplying?'
How do you remember to breathe? BREATHES DEEPLY
'I'll be tracking down answers to lots of burning questions...'
HIGH-PITCHED LAUGHTER
I feel quite a strong desire to urinate.
But don't. OK.
'..from what exactly is in our farts...'
So, this device, which we colloquially refer to
as the Thunder Funnel...
MICHAEL LAUGHS That's great.
'..to how long we take to digest our food.'
CLARE: Are you wearing it overnight? Absolutely.
'I'll show you how we can all live healthier, longer lives.'
MONITOR BEEPS
This is one of the most impressive things
I've seen for a very long time.
'And I put my body to the test...' Hey.
'..to help you at home...' Oh!
'..understand yours.'
That's stuck.
Get ready to see yourself...
Ooh!
..in a whole new light.
'This time...'
What is the best way of improving your brain health?
Is it crosswords? Is it Sudoku?
It's something that's going on in here.
'I'm thrown in at the deep end,
'trying out a surprisingly enjoyable way to keep our brains young.'
We love it. It's an energy that you cannae explain.
'Can you stave off muscle weakness as you get older?'
I just get a buzz, particularly competing.
'Staying active well into our 70s
'is more achievable than we might think.
'And... with one in five of us
'likely to develop breathing problems at some point,
'our cameras follow surgeons as they battle against the clock
'to perform a pioneering lung treatment.'
SURGEON: We've only got a safety window of 20 or so minutes
before there will be irreversible damage.
We're heading out on another extraordinary journey
around the wonders of your body.
'First, something our bodies just can't avoid.
'Every year, hundreds of thousands of Brits come down with the flu.
'The viruses that cause it are released
'when someone who's infected coughs or sneezes.
'So, how does your body try to prevent being invaded
'by these invisible microbes?'
Our body has lots of defences to try and prevent those microbes
from getting inside.
Now, my face, for example, has quite a few holes in it.
My nose, my mouth.
If we have a look inside my nose, we see lots of hairs.
Tiny particles carrying microbes get trapped by the hairs,
and later, what happens is you blow them out into your hanky.
Or, perhaps, you swallow them
and they go down into the acid of your stomach,
which destroys them. Ingenious.
But what happens when harmful microbes like viruses
get past the first line of defence,
entering your lungs and bloodstream?
As virus particles begin to multiply,
your immune system springs into action.
It's the start of a battle
between your body and the infection.
SNEEZES
The flu is more dangerous for older people
because your immune system weakens as you age.
In this London clinic, they do something extraordinary.
The invitingly-named FluCamp is run by hVIVO,
who are experts in clinical trials.'
Drop two drops in your nose, please.
Volunteers check in for a holiday with a difference.
SCIENTIST: Right nostril, one.
They're given a dose of flu high up in the nasal cavity,
bypassing the nose's hairy first line of defence.
EQUIPMENT BEEPS Left nostril, two, 12:15.
These volunteers have already had a flu vaccine.
SCIENTIST: Perfect. Thank you very much.
The team will monitor how well the vaccine protects
against this particular strain of flu.
This is just day one of a week-long stay for Mark Gales.
I just sneezed. Not once, but twice.
So, are my symptoms starting? Only time will tell.
Once inside the body,
the viruses trigger our mucus-making machinery
to go into overdrive. CLEARS NOSE
This is your body's way of trying to trap...
WHEEZING COUGH ..and clear away any new invaders.
Becoming blocked up and congested can be really unpleasant.
So imagine how you would feel
if you had a really serious breathing problem.
50 miles north in Cambridge, 67-year-old Clifford Young
has been admitted to hospital with breathing difficulties.
Since I almost passed out,
I realised that something was seriously wrong.
I was previously one of the most fittest person on the planet.
HE LAUGHS
MUSIC PLAYS
I love dancing. Used to do a lot of Latin dancing.
Very fast, very active.
It was very difficult to get me off the dance floor.
MAN: And I'd like you to take a deep breath in.
All that changed around a year ago,
when Clifford found he was struggling to breathe,
and even passed out a few times.
Worryingly, a scan revealed he had clots in the blood vessels
that provide his lungs with blood.
This is a life-threatening condition called pulmonary embolism,
and it affects as many as 60,000 Brits each year.
DEEP BREATHING
Your lungs supply your blood with oxygen,
and do this thanks to some extraordinary engineering.
HEARTBEAT THROBS
Each lung contains millions of tiny air sacs.
These delicate structures
are particularly prone to damage from smoking,
as they can't always repair themselves.
Each lung contains nearly half a billion of these air sacs,
giving them a huge surface area.
It's here, inside these sacs, that oxygen is able to pass
into the lung's vast network of blood vessels.
But in Clifford's case, the blood is struggling to get through.
That's when they find out there's clots on both sides of my lungs.
That's when it really hit me. I said, "Oh... You're gonna die."
It's not Clifford's airways that are blocked,
but the blood vessels in his lungs.
MONITOR BEEPING
Clifford's only hope is a radical operation
performed by senior consultant David Jenkins
here at the Royal Papworth Hospital.
The patient's had a pulmonary embolism,
which is simply a blood clot to the lung arteries.
The vast majority of people with a blood clot in their lungs
can be treated with blood thinners, but in Clifford's case,
the clots have become immovable masses of tissue
that are blocking major blood vessels in his lungs.
His heart has to work harder and harder.
Left untreated, this would lead to heart failure.
But removing these clots is going to be tricky.
The lungs are relatively inconveniently located
in the middle of the chest
and ordinarily have five litres of blood per minute
flowing through them.
The surgical team has the technology
to see exactly where the clots are,
but to remove them,
they will need to first remove all nine pints of Clifford's blood.
We need to completely empty the blood vessels of...
of blood, so we can see what we're doing.
But without blood, your brain can't survive more than five minutes.
Hello there, Mr Young. How are you?
Hi. I'm fine, thanks, Mr Jenkins.
It's a major, major event for you tomorrow.
No, just wake me up.
CLIFFORD LAUGHS Yeah, we'll make sure of that. Yeah.
We've got Clifford Young today. He's in his mid-60s.
Symptoms of breathlessness. Quite a lot of disease.
As part of Clifford's operation, his heart will be stopped.
But the riskiest part of the whole procedure
is having the blood drained from his body.
Still a bit nervous how the outcome is gonna be,
but, hopefully, that...
I give them my trust.
The surgeons are prepped,
and Clifford is taken to the operating theatre
for what is set to be an eight-hour procedure.
MR JENKINS: And how are you feeling? I'm feeling fine.
'Coming up...
'How do older brains learn new things?'
WOMAN: Are you ready to go? Yep.
OK. Starting now.
'I show you ways to keep your brain sharp,
'even as we get into older age.'
All will be revealed shortly, yeah?
'I swallow a tiny video camera
'to learn more about our digestive system.'
Well, beautiful, isn't it?
'And I go to war with the flu virus
'to reveal your body's powerful, hidden defences.'
MICHAEL MOSLEY: 'Wherever you live, whether in the countryside,
'or in the city, surveys suggest that as many as one in two of us
'report problems with our digestive systems.
And as we get older, our struggles can get worse,
particularly things like constipation
and irritable bowel syndrome.
Most of us will never get to see inside our guts,
but I'm about to get that chance.
I've come to meet Gill Fry,
an endoscopy nurse at the London Clinic.
So, for this test, you'll need to wear
this quite wide belt around your middle.
So, let's get it comfortable first.
Over your head. Yep.
And then that comes around here.
'The belt contains a device that will record video
'captured by this tiny camera the size of a pill.
'It's normally used by doctors to inspect your gut.'
What happens to it at the end?
You may see it when you go to the loo.
HE CHUCKLES You might see it...
I might hear it go tinkle, tinkle, as it hits the porcelain. Yes.
And before you do anything, if you could take a selfie
by pointing it slightly the other way, towards you. Perfect.
OK. So, the flashing lights and camera crew are ready.
SHE LAUGHS There we go.
Exactly. Smile.
Just take it in your own time.
Uh-huh. It doesn't matter which way it goes down.
It's in your mouth at the moment.
HE GULPS AND GASPS
It's going down your oesophagus,
into your stomach. HE GULPS AND GASPS
Oh, there it goes. Blimey. And we can see that it's...
Wow. ..in the stomach.
It's already in the stomach. Wow.
Yeah. That was fast. It's just a matter of seconds.
'The tiny camera is setting off
'on its incredible voyage through my guts.'
Weird, isn't it? To think that that's going on inside you.
And my poor stomach's wondering what it's got here. Yes.
There's clearly something it can't digest. That's right.
'Let's give it something to look at.'
I wondered if I could do a little demo.
I've got some sweetcorn over there, so... see if they pop up on camera.
Oop. Something's happened.
That's them, I reckon. The little... Yeah.
Yeah? They came... Ooh, that's fast, isn't it?
Yeah. Very fast. Got right down there.
The camera battery should last at least 12 hours,
so I'm not expecting it to beam back pictures of the whole journey,
as the typical gut transit time for food
is around one-to-three days.
Even longer if you're constipated.
I would expect the camera to stay in my stomach for a couple of hours.
That's typically how long food spends getting churned up
by the strong muscles of the stomach
and its acidic gastric juices.
And before you ask, the reason we don't digest ourselves
is because the stomach is lined with acid-proof mucus.
Surprisingly, women tend to have longer guts than men,
probably because they need to absorb more nutrients
when pregnant or breast-feeding.
I'm now heading off home.
I've got all the kit under this lot,
and I'll be fascinated to see what happens next.
As far as I know, it's still in the stomach,
but it should be making its way down to the small intestine shortly,
and it'll be interesting to see what it looks like down there.
And then, finally, will make its way to the large intestine.
It's now been just about an hour,
so hopefully, it's well on its way.
Our guts do much more than simply digest food.
They are also home to trillions of microbes
that play a critical role in protecting us
from all sorts of infections.
At FluCamp, volunteer Mark's immune system
seems to be protecting him against the flu.
'But down the years,
'plenty of others have not been so lucky.'
Now, this is very nostalgic.
It's a photograph of me with my older brother John,
and it was taken in 1957.
And just at that time,
there was an outbreak of a deadly flu
which killed up to four million people worldwide,
and I was struck down with it.
But I survived, largely thanks to my immune system.
Since then, well, I've had lots of other infections,
but my immune system has always managed to get on top.
So, how exactly does the immune system
help us fight off deadly infections like viruses?
'Before I answer that question, I'm heading off to the flu centre
'to have a blood test to see what, if any, immunity I have
'to the common strains of flu that are currently circulating.'
Hi, there. Hello. Good morning.
Good morning to you.
All right. You'd like to draw my blood, would you?
Yeah. I've got good veins.
'A couple of vials are expertly drawn
'by phlebotomist Melonie Ogaribo.'
Thank you.
How does our body react to invaders?
This white blood cell, the grey blob,
is hunting down and engulfing bacteria, the green blobs.
And when the body is infected by a virus,
it reacts in a similar way.
'But viruses pose a special challenge to your immune system
'cos they can mutate so fast.
'OK, I want you to use your imagination here,
'and picture the inside of your body as a battlefield.
'I am a heroic white blood cell,
'and the red team are nasty flu viruses.'
LASER BLASTS
'My job is to protect the human body,
'and I do that by roaming around
'looking for potentially dangerous invaders.'
LASER BLASTS
'When the body first encounters a new virus,
'it really doesn't know what to do.
'It is only when it's attacked that it knows how to respond.'
LASER BLAST, ELECTRONIC BLEEPING
Hooray!
'Chemical signals now gear up the body for war.'
Your body is now able to produce a giant,
cloned army of killers
whose only job is to seek out and destroy that particular virus.
'Every new virus is a new enemy for your immune system.
'But the good news is it's a fast learner.
'The immune system remembers what that particular virus looks like,
'and the next time it encounters the virus...'
QUICK BREATHS
..we're ready and able to shoot and destroy it.
LASER BLAST Remarkable.
'So, what have my blood tests revealed?'
The results are in, and it's good news.
Turns out that I have immunity to all common forms of flu viruses
which the FluCamp team are currently doing tests on,
and which they predict are likely to be on the rise.
And that, in turn, means that I'm extremely unlikely
to get flu this winter.
All thanks to my immune system. Hurrah!
Here are three top tips for keeping your immune system in good shape.
Get a good night's sleep, as that is when your body repairs itself.
Take vitamin D...
..and exercise, as that increases the number of immune cells
circling around your body.
When it comes to exercise,
particularly exercise in the great outdoors,
we are spoilt for choice.
Like the hills of the glorious Lake District.
I'm Wendy Dodds, aged 72.
I live in the Lake District,
and one of my main activities is fell running.
Despite being in her 70s,
Wendy is still able to run long distances over hills and mountains.
I just get a buzz, particularly competing.
You know, the thrill of sort of hoping to try, at least,
to catch one or two of the folk that are ahead.
I found that I was performing better at long distance,
so, I was never very good at shorter distances.
But how did she do what, let's face it,
the vast majority of us would struggle to?
I had a muscle biopsy done.
The results showed that I had approximately
88% slow fibres in my thigh muscles,
which is one of the reasons
that explain why endurance was much more suited to me.
So, what are the slow muscle fibres that Wendy has in such abundance?
Your muscle's actually made up of lots of individual muscle fibres
tightly packed together.
And these muscle fibres come in different types.
One type are called fast twitch because they contract really fast,
helping you react and move at speed.
This type works for short spells without needing oxygen,
but that means they tire quickly.
We also have another kind of muscle fibre which is built for endurance.
It relies on oxygen from your blood.
It can keep going for much longer.
It's called a slow-twitch muscle fibre.
Most of us have roughly 50% slow-muscle fibres.
Wendy has 88%.
Wendy has maintained her muscle mass by doing lots of running.
But what about the rest of us?
Well, your muscles need to be stretched and stressed
to remain strong, which means as we get older,
most of us lose a lot of our fast twitch fibres.
As we age, we slow down,
and therefore there's less stress put on fast fibres,
so they tend to degenerate at a greater rate than the slow fibres.
Fast or slow, after the age of 30, unless you exercise,
you can lose up to 5% of your muscle mass every decade.
That leads to less mobility
and an increased risk of falls and fractures.
But you can keep your muscles stronger for longer
by doing resistance exercises, running,
or even just going for brisk walks before dinner.
And speaking of dinner,
I wonder how my little pill camera is getting on.
'Something isn't right.
'I would expect the camera to be in my intestines by now,
'but I can see the folds of my stomach lining,
'which means it's still in my stomach.
'This is very odd.'
Ooh, that's gross.
'Maybe it will move on during the night.'
Across the country in Cambridge...
..Clifford is preparing to have surgery
to remove deadly clots from the arteries in his lungs.
Just rest back. 'How do I feel about the surgery?'
Erm...
apprehensive, as anyone can be, because I don't know what to expect.
'Probably the only way I would get back to some sort of normality.'
I'm not surprised Clifford is apprehensive
because this will be a complex operation
involving several critical stages.
Surgeon David Jenkins makes the first cut, to open up the chest.
SAW WHIRRS
MONITOR BEEPING
MR JENKINS: See, the heart is beating away,
and it's... it's not really disturbed too much by me.
So, we don't want to irritate or upset it too much.
During this extraordinary procedure,
the first major step is to drain Clifford's body of blood,
so they can find and remove
the lumpy clots blocking his arteries.
And we can put a big pipe in.
A tube is carefully attached
to divert the blood out of his body.
And that's through to you.
And all the blood from his body is coming out now
and going into the machine.
Without blood,
you'd normally suffer brain damage within five minutes,
but the team at the Royal Papworth Hospital have a way round this.
So we're all set up now to cool the patient down.
They're going to cool Clifford down
to dramatically reduce his need for oxygen.
So, we've cooled to 20 degrees, yeah?
The whole patient's body is almost half what it normally is.
MONITOR BEEPING
This will extend the time Clifford can survive without blood.
Trickle on plegia, please.
Clifford's heart has been stopped.
He's got no blood, and he's not breathing.
This is a critical moment.
The surgical team have reached one of the most delicate
and risky stages of the whole procedure.
So, we've safely, probably, got about 20 to 25 minute's time
before there's irreversible brain damage.
So we've gotta work reasonably quickly.
Time is very much against me,
and during that period, the patient is at big risk.
So it's that real balance of operating against the clock.
Even if David can grab hold of the clots
which are blocking Clifford's arteries,
there's no guarantee they will come out easily.
'Coming up...
'how does my old brain measure up against the younger generation?'
Are you ready to go? Yeah.
'I find out if you can teach an old dog like me new tricks.'
'Are you ticklish? I am.
'I'll show you why this is an unexpected wonder of the body.'
HE LAUGHS 'And I head to the local butcher...'
I haven't seen a sausage this long. HE LAUGHS
'..to illustrate what it is
'that makes our guts so good at their job.'
MICHAEL MOSLEY: It's been 18 hours since I swallowed a pill camera
in my attempts to provide us
with an inside view of the digestive system.
So, how long did it take the pill cam to get through my body?
Well, the honest answer is I don't know because I haven't seen it yet.
'In the mystery of the missing pill camera,
'its last-known whereabouts are revealed in this footage.
'It was still in my stomach when the battery died.'
'But how long does food normally take to pass through your body?'
Well, that typically takes anywhere between 24 and 72 hours.
In other words, around one to three days
to get from there to there.
By now, I would have expected the camera to pass from my stomach
into my small intestine, and from there,
to my large intestine.
You might think the camera is moving slowly
because it's indigestible,
but it's a myth that tough foods like meat
take longer to move through.
My main concern now is that at some point, it comes out.
'While we're waiting for that to happen,
'I've come up with a different way to illustrate
'just how long and complex your guts really are.
'I'm off to the high street to do a demonstration.'
Hi, there. Hello. Hello.
I've come to make sausages. Here we go.
These are the actual intestines from a hog.
MICHAEL CHUCKLES OK. Right.
So, this is what intestines actually looks like.
Human intestine is around five metres,
and that is 15 to 20ft long.
The reason we have such a long gut is basically
to extract as much nutrition as possible out of the food we eat.
'I'm going to make a sausage
'roughly the same length as your intestines.'
And this kind of uncannily looks like a human intestine,
I have to say,
cos it's about the right width for the small intestine, certainly.
'Most of the nutrients, salt and water we consume
'are absorbed in the small intestine.'
The small intestine is the first part of your intestines,
the bit which is next to the stomach,
and where most of the absorption takes place.
That's why you need so much of it.
And the large intestine would be much, much fatter,
basically about twice as fat, and it ends up in your bum.
HE CHUCKLES
Once upon a time, before we had cooking,
our guts were probably even longer than they are now.
They've shrunk down a bit because cooking
has made it much easier to absorb nutrients.
It is amazing to think that you've got five or six metres
of this sort of thing inside your torso,
and, somehow or other, it all packs in and keeps on doing its job.
I think that's really impressive.
And if we take a really close look, it's even more impressive.
The walls of our intestines are lined with little blobs.
They're called villi, and there's billions of them wafting around.
If we zoom in even closer,
we can see each one is covered in its own tiny bumps
called microvilli.
All these bumps upon bumps increase the surface area of the gut
at least ten times, which, in turn,
allows us to absorb more nutrients from our food
which is critical to keeping us alive.
And speaking of massive surface areas,
did you know the largest organ in your body is your skin?
It contains millions of sensory receptors
which alert your brain to all manner of sensations,
including feeling ticklish.
There are apparently two different types of ticklish sensation.
There's one called knismesis, this sort of gentle tickling,
where you have the small hairs on your arm,
and you're slightly caressing them.
'This type of tickling is an alarm system.
'It alerts you to things that land on your skin
'like nasty little blood-sucking insects,
'so you know to swat them away.
'It is so sensitive that your hairs alone can trigger this feeling.
'The bug doesn't even have to be on your skin.'
The second type of tickling is called gargalesis.
'It's the one that makes you laugh.'
There's more pressure,
and it's applied to the ribs and other sensitive areas.
What's interesting about this is you can't do it to yourself,
however much I, you know, squeeze and prod.
And that seems to be because there are areas in my brain
which are linked to motion, are also sending messages out
to other parts of my brain associated with touch,
and saying, "Don't bother.
"You don't have to respond to this at all."
Right. Nothing going on.
'My wife Clare is now going to help out.'
LAUGHING: So, why is it different when Clare tickles me?
Well, it's partly because it's...
LAUGHS ..completely unexpected.
And the other odd thing is that although I'm quite enjoying it,
there's a part of me that just kind of wants to bat her away.
And that seems to be because
when you get tickled, particularly unexpectedly,
it activates an area of the brain called the hypothalamus.
That sends out danger signals to the rest of your brain,
telling you that someone unexpected
is doing something a little bit odd to you.
They might be about to stick a knife in your back, so you should be wary.
On the other hand, it's also quite funny.
It makes me laugh. And that, apparently...
LAUGHS ..is a sign of submissiveness.
I am telling Clare that she's dominant.
Thank you very much. Over and done.
You won. SHE LAUGHS
So, it turns out there is a lot more to tickling than you might think.
'Like the tickle response, other parts of your nervous system
'are dominated by the supercomputer you carry around in your head,
'your brain.
'The brain is a remarkable organ that goes on learning new things
'even when we get older.'
LAUGHTER Whoa-ho!
'There's a lot of interest in studying how children learn,
'which is hard because they don't keep still.'
On the seat for me.
'So, scientists here at the University of Nottingham
'have been collaborating in a marvellous invention,
'the world's first wearable brain scanner.
'And they're letting me in on the fun.'
How does that feel? That's fine.
Perfect. Tuck in my ears.
Yep. Yep.
'The idea is to see what happens in my 66-year-old brain
'when I try to learn something new.
'Professor Matt Brookes is running the show.'
Hi, there. Hi, Michael.
How are you doing? Fine, thanks.
So, what we're doing with this machine
is we're looking at how different parts of your brain
connect to each other. Oh.
You're gonna see a series of words on the screen. OK.
And when you see a word, we want you to write it down. OK.
And with the right hand cos I'm right handed, yeah?
Yeah. But then we also want you to try to do it with your left hand.
OK. All will be revealed shortly, yeah?
Thank you very much. OK.
Good luck. Looking forward to it.
'This revolutionary brain scanner is already being used
'to gain insights into conditions like epilepsy and Alzheimer's.'
WOMAN: Are you ready to go? Yep.
OK. Starting now.
Are you ready to go for the left hand? Yep.
'As far as my brain is concerned, I'm learning a new skill,
'and the helmet records my brain activity while I'm doing it.'
OK. That's finished. We're gonna come get you out now.
I haven't written with my left hand or even attempted to do so for many,
many years, so I was impressed that I could write anything
even faintly coherent.
So, what was going on inside my head?
You might think that when you learn something new,
you grow more brain cells.
ELECTRICAL FIZZING
And it's true that we go on
producing new brain cells throughout our lives.
However, it's not the number,
but how well-connected your brain cells are
that makes the difference to how well we learn.
But it'll be really, really interesting
to see what the results look like.
I'm assuming this is my brain, yeah? This is your brain activity.
OK. This is when you're writing with your right hand.
You can see a nice bit of activity right where it should be. Spot on.
And it's on the left hemisphere, isn't it? Left hemisphere.
Cos I'm writing with my right hand? Yeah, yeah. Yep, OK.
So, now if we look at what was happening
when you're using your left hand... Ah.
So, here we sort of naively think, "Well, OK, it was over here before.
"It's gonna be the opposite side." But it's not.
Ah. It's both sides of your brain lighting up.
'And seeing that really was a big surprise.'
What's lovely about it is it's an absolutely wonderful example
of the two bits of the brain working together. Yeah.
The left hand was much harder.
And so presumably, at some point early on in the process,
the other side of my brain went,
"OK, I'd better help this bit out." Yeah.
That's wonderful.
It's lovely to do an experiment like that, and it actually works.
What's really encouraging about this new research,
particularly if you're a bit older, is it demonstrates
it's not just the number of brain cells up there that counts,
but the richness of the connections between them.
And what is so great about our brilliant brains
is that we can go on developing new skills
and growing new connections whatever our age.
And later, I'll reveal an intriguing way to do just that.
Back in Cambridge...
..Clifford's operation has reached a critical point.
His blood has been drained from his body,
his heart has been stopped,
and his body has been chilled to just 20 degrees.
This procedure is effectively using medically-induced near-death
to save his life.
The next step is to find and remove the clots.
MR JENKINS: We've only got a safety window of 20-or-so minutes
before there will be irreversible damage.
Ah.
So, that's the clot.
Octopus of clots from all the branches.
If left, these clots, which have become thick and fibrous,
could have completely blocked the vessels
supplying his lungs with blood.
That was a bit of a struggle, that.
So, we finished the dissection on the right side.
There was actually quite a lot of disease.
And then we'll go and change round and do the same on the left side.
Even when Clifford's blood vessels are clear of clots,
the operation is far from over.
Now comes the delicate job of bringing him back to life.
Quite pleased that we found what we expected,
and we were able to clear all the major blockages.
And we were just inside the 20 minutes.
Back up slowly, then, thanks.
After slowly warming Clifford up,
the next crucial step is to return his blood back to his body.
Only then can they restart his heart.
David won't relax until he sees a steady heartbeat.
That's gone back to a more regular rhythm now.
We don't want it using too much energy.
And that looks as if it's back to a relatively regular rhythm.
So, that's good. So, all finished, yeah.
And looking at the pressures
and the numbers and everything are looking really good.
So, very pleased. Yeah.
So, now what we do is we lay the specimen out
to have a look at what we've cleared.
This looks very good, so, yes, very pleased so far.
When you see what they had to remove from Clifford's lungs,
it's staggering.
And by clearing it, it's quite satisfying.
We take it all out, and then, hopefully,
the patient goes on to make a good recovery.
Clifford's surgery went well and took just under six hours in total.
'Coming up...
'I'll reveal great ways we can all keep our brains young
'as we get older.
'And will Clifford manage to get back to his old dancing self again?'
On a clear night, if you look up into the night sky,
you can probably see around 6,000 stars.
And if you were to come into an observatory like this one,
well, you'd see a lot more.
But just in our galaxy alone,
there are around a hundred billion stars,
which is a huge number.
But that number is dwarfed
by the number of brain cells you have up here.
Your brain never stops.
Right now, it's working out what you can see or hear,
what you can feel or taste.
It does that by constantly making new connections between neurones.
Earlier, I promised to show you a great way
to keep your brain fit as you age,
and the answer is something most of us really enjoy doing.
In a hall in Glasgow, it's time for a community group's weekly meetup.
If you take up this hobby, it will help keep your memory sharp...
We have to think about it. We have to practice.
It is a brain workout.
..and allow you to focus on tasks for longer.
So, what is the best way of improving your brain health?
MUSIC: 'One Jump Ahead' by Trevor Duncan
It's dancing.
You get on the dance floor.
You're inspired just to shake your booty.
Oh, it's just great, isn't it? They are clearly having so much fun.
Among the swirling and twirling
is brain expert Dr Louise Nicholls from the University of Strathclyde,
and she has some top tips to keep your brain in good shape.
SHE LAUGHS, CHEERING AND APPLAUSE
So, I'm used to the idea that as you get older, your brain shrinks.
The evidence is showing that it's possible to maintain brain size
and function into older age, but even to go the other way,
to actually improve it. Wow.
Louise has three tips to keep your brain young.
Number one, get active.
Dancing's a perfect example because it gets the blood pumping
which helps the brain in terms of improving the blood supply,
the oxygen flow.
Doing daily crosswords and puzzles may help a bit,
but if you really want to improve your memory and concentration,
getting more active can produce results in as little as six months.
Foxtrotting on to tip number two. Learn a new skill.
When people have learned a new skill,
after a few months, we see evidence that the older brain
actually behaves more like the younger brain.
Wow. So, that we're gaining more connections among cells.
Amongst, actually, different brain regions as well.
We want to keep challenging ourselves to learn new things.
If you think about doing an actual dance routine,
then you have to learn the steps.
You have to go quite quickly, probably.
New routines are learned over time.
Learning new routines is hard,
which is why dancing is far better than something like a crossword.
Different parts of the brain are challenged in multiple ways
keeping the brain on its toes.
Pivoting onto tip number three. Being social.
Oh, I love it. I love it. I need it for my mental wellbeing.
You feel alive. You're part of a social circle that is wonderful.
It's the best high.
It's important, particularly as we age,
to maintain and even improve our social networks.
These can be important for our anxiety and stress levels.
Studies have shown that people who increase their social circles
have a lower risk of dementia.
OK, old dog going on the dance floor.
Left, right. Left, right.
Left, right, left. Get them together.
'But what if dancing is not for you?'
Whoa!
'How about singing with a group or learning a new sport instead?'
Your brain is like a muscle. Use it or lose it.
That means finding something which is challenging intellectually,
which is physically demanding, and which, above all, is sociable.
Yay! Keep going.
Talking of, "Use it or lose it,"
just three months since his life-saving lung surgery,
67-year-old Clifford is slowly getting his life back.
CLIFFORD: 'Just to give an update on my recovery after surgery.'
And remember, before surgery, I couldn't do five-minute walk.
I am back in the gym now, working out, which is wonderful.
MUSIC PLAYS
'What's even better? He's also back on the dance floor.'
'I feel 100%.'
'It just goes to show the body's amazing ability to recover.'
I have spent decades exploring the human body,
and I'm still amazed at the way the organs,
tissues and cells work together to make us who we are.
'We've been on an eye-opening journey around our bodies.
'We've met some amazing people
'who have shared their incredible stories with us
'to help us all understand our bodies a bit better,
'and to demonstrate how we can all live healthier and longer lives.
'I have, of course, offered up my own body for experimentation.'
Whoo!
'Above all, remember, if you take care of your body,
'it will take care of you.'