The Science Museum in London is being prepared for a most peculiar event.
Here live in front of hundreds of people an alien world is about to be explored.
Mosley: Oh, God.
Keep going. Keep going.
Mosley, voice-over: It will be scrutinized...
And probed.
Oh! Oh! Oh!
Mosley, voice-over: Our guts...
a mysterious place
of writhing tubes,
corrosive acid,
pulsating muscles.
Mm...
Mosley, voice-over: Their dirty work, normally invisible,
is about to be laid bare in all its gruesome detail...
And the Guinea pig for this...
Ha ha ha!
Well, that'll be me.
During my medical training and more recently
as a television presenter, I have taken part
in some pretty bizarre and painful experiments,
but nothing quite like this.
Announcer: This program was made possible in part
by contributions to your PBS station
from viewers like you.
Thank you.
Mosley, voice-over: There's a new attraction at the science museum today.
For one day only, my intestines are going on display.
I want to do this because I'm curious.
The digestive system is something we all have
but know so little about.
My guide is gut expert Dr Mark McAlindon.
Hi, Mark. Hi, Michael.
Nice to meet you. And you.
This is a very theatrical setting, isn't it?
It is.
It's not a conventional medical environment,
but there we go.
I think we're gonna have some fun today.
I think so, too. Right.
So what happens next?
Ok. So first of all, stick this one in.
Ok. Ooh, cold.
Mosley, voice-over: Mark is going to monitor me
as I eat a typical day's food,
and we'll all watch what happens as it goes on its merry way.
These lucky visitors will see parts of me
that have never been seen before.
That's up. Ask you to put that over your head.
Sure.
Mosley, voice-over: We're using the very latest technology...
a miniature camera inside a pill.
It will, hopefully, travel through me
and transmit live pictures from the depths of my guts...
And as it goes, I'm gonna take part in a number of tests.
It's a leap into the unknown.
We'll be trying things today that few have tried before.
McAlindon: Lie down.
We'll just do your pulse and blood pressure.
Ooh, elegant chaise lounge here.
There is one, which is just as well.
It means you're as fit as a fiddle, fit to go.
Marvelous, fit to swallow pills.
Mosley, voice-over: Once swallowed, I'll have no control of the camera.
The murky world of my intestines is a law unto itself,
and how long it will take the camera
to work its way through is anybody's guess.
16 hours. A few days.
One day. Two days.
Two hours.
Mosley, voice-over: Food can take up to 3 days
to travel through the gut, but last night,
I drank 4 liters of laxative to clear the way.
So I'm expecting my camera
to travel rather more quickly than that.
Ok, Michael.
Well, I'll give you the pill camera,
and if you'd like to take it out of its holder,
if I can actually manage that...
right. Ok.
Mosley, voice-over: This pill houses a mini film crew,
complete with lights and camera.
It wl take pictures 3 times a second
and transmit them to screens here in the science museum
via sensors on my body.
So, Michael, ready when you are. Ok.
You pop that into your mouth,
a few gentle sips of water.
[Gulp]
Uh! That's in.
Has it gone? It's gone.
It's gone on its long journey.
I can't get it back. It's too late.
Mosley, voice-over: My first feeling is one of relief.
The camera is clearly working as it slides
down the back of my throat and heads towards my stomach.
Ha ha ha! It's very funny.
Ha ha ha!
Mosley, voice-over: Propelling the camera down
are powerful muscles that line my gullet, or esophagus.
McAlindon: Anytime you swallow food,
the esophagus will be able to tell
that there's a force on its wall,
and that initiates the process of contraction
of the muscles to try and push it further down.
Mosley, voice-over: It's really quite magical.
McAlindon: So this black hole here,
soon you'll see the capsule passing into the stomach.
Here it goes. Ooh, there it goes.
Mosley, voice-over: Down here,
it's a cavernous, alien landscape,
and you can see some white blobs of porridge I ate for breakfast,
but what's really striking is,
there is so much pulsing and throbbing movement going on.
It's something we're normally completely unaware of,
but it's happening all the time
and throughout our digestive system.
Our guts are a tireless machine,
and I spent a morning in the run up to this exhibition
having some scans to find out
just how the different parts work together.
I've seen my heart beating, my brain buzzing,
but I've never seen my guts in action.
Well, lucky me, today I get that chance.
Mosley, voice-over: Here at University College Hospital,
Radiologist Stuart Taylor and his team
are using a stop-motion technique
to capture the unconscious movement involved
in a journey through our guts.
To get the best possible images,
I'm knocking back a rather disgusting drink.
Taylor: So this liquid has got a special sugar in
which isn't absorbed by your body
so when we do the scanner, we'll be able to see
the inside of the bowel very well
and how the bowel works and moves.
It's an acquired taste, isn't it? It is.
Probably not something you'd choose
to drink every day, but hopefully not too bad.
Michael, I am going to start a few brief pulse scans now, ok?
Breathe in and hold your breath.
Mosley, voice-over: As I hold my breath,
the team takes a series of high-speed images.
This is the last scan.
Mosley, voice-over: These will be stitched together
to form a 20-second film of my guts in action.
Technician: All finished. Well done.
Mosley, voice-over: This technique is normally used
to diagnose disorders affecting movement in the gut.
That's absolutely fascinating.
What surprises me is just how much movement there is in here.
You know, it really is a dance.
Mosley, voice-over: I was lying completely still in the scanner,
but this slice through my guts shows they were anything but.
Any food passing through my digestive system
takes the same route through this pulsating,
writhing, continuous tube...
down my gullet and into my stomach,
then into my small intestine, or small bowel.
Next stop, it's the large intestine,
otherwise known as the colon...
And then it's out the other end.
It's this constant movement throughout our guts
that enables our bodies to transform food
into the nutrients that keep us alive.
Back here at the science museum,
the camera has traveled down my gullet
and into my stomach,
where it's transmitting live pictures
to an enthralled audience.
Now it's time for some food
to start its journey through my guts,
and Mark has got something else to view it with.
The pill camera is still down in my stomach.
We're about to stick another camera in
which is slightly intimidating-looking.
It's got a nice tip there,
and it's gonna go down through my nose.
It should be fairly unpleasant,
and when it's down there,
we'll get a much better look at the stomach,
and then I get to eat a little bit
so we can sort of see more of the stomach action.
So this is gonna be a little bit uncomfortable, isn't it?
A little bit.
Mosley: Oh, God, brings tears to your eyes.
Ooh, that is uncomfortable.
There we go. There we go. Oh, dear.
Mosley, voice-over: Although this camera will only go
as far as my stomach, it is steerable
and should give higher-resolution pictures.
Oh, that was so uncomfortable.
McAlindon: And there we are into the stomach,
and there's some porridge from earlier. Ha!
You ok, Michael? Yes.
I know it's not the perfect position to be dining,
but would you like to try a little bit of something?
How about if we go for something with color?
Ok. Something red?
That sounds good, a few bits.
A few bits of yellow. Yep.
So we should see it passing by in a minute.
Ah, there we go.
Yeah. Something green went past.
Mosley, voice-over: You can see the way the food
is being churned up by muscles in my stomach wall.
As well as this mashing action, my stomach is also releasing
gastric juices and began doing so
long before I started eating.
Gastric juices are released at the sight, smell,
or even thought of food,
and the powerful chemicals they contain
will help turn these lumps of food
into a creamy mush known as chyme.
Oh, nice.
But I don't think I can bear having this camera
down here any longer.
Coming back.
Oh, that's horrible.
Out your nose.
Oh, horrible, horrible, horrible, horrible.
Oh, God! Bloody hell, that was horrible.
Ach! Ah... Ohh!
Agh...
Mosley, voice-over: To see my food sloshing around
in my gastric juices was a novel experience,
but it wasn't a camera that gave us the first insights
into the workings of the stomach.
It was actually a gunshot wound that revolutionized
our understanding of human digestion.
[Bell tolls]
[Car horn honks]
Our story starts in June 1822
when a young man is accidentally shot in the chest.
[Gunshot]
The victim was Canadian boatman Alexis St. Martin,
working on the shores of lake Michigan.
The blast ripped through his ribs, his lungs,
and the front wall of his stomach.
Mosley, voice-over: First on the scene was young army doctor William Beaumont.
He dressed the wound
but really didn't expect his patient to live...
But survive he did, and I've come to meet
medical historian Lindsey Fitzharris
to find out how this unfortunate accident
went on to lay the foundations of modern gastroenterology.
Hi. Hi, Lindsey.
So, this is an actual diagram of the original wound,
and you can see the outline of it.
It was really big.
When St. Martin was shot, it was about the size
of a man's palm, essentially.
Wow, that big.
Very big. Yes.
It was on the left side of the chest,
right about there.
We tend to think of the stomach being low,
but it's actually much higher up,
right below the diaphragm.
When he was shot,
parts of his undigested breakfast
began pouring out along with bits
and pieces of his torn stomach,
but Beaumont is called to the scene,
and over a course of a year,
he's able to nurse Alexis back to health,
and what happens to this giant hole
is that it shrinks, and it forms
this 2.5-centimeter-diameter fistula.
Right. So you've got the original whole
the size of my palm, and it's shrunk right down,
yes. But it's still open.
It's still open, and through that fistula,
he can see directly into the stomach.
It was an incredible opportunity for Beaumont
to study the living digestive system
in a way that no other surgeon or physician
had been able to do until that point.
Mosley, voice-over: Beaumont certainly made the most of this opportunity.
Once his patient had recovered, he employed him as a handyman
and studied his stomach for the next 10 years.
Fitzharris: He subjects St. Martin to a series of experiments,
and he takes little bags like this,
and he wraps pieces of food in these bags...
cabbage, meat, all kinds of things...
and he sticks it directly into that fistula.
Right. Very nice.
So he just pops it into this convenient hole there...
Pops it into the stomach, yes.
Leaves it there to brew for a while
exactly. Yes. Sort of like a cup of tea,
and then brings it out and inspects it.
He was very interested in how different condions
affected the digestive system,
for instance, if it was cloudy,
if it was sunny, if it was cold.
Mosley, voice-over: As well as putting things into St. Martin's stomach,
Beaumont also sucked out the juices
that were produced there...
And it was these previously inaccessible bodily fluids
that were to turn popular beliefs about digestion
on their head.
Mosley: Did he know what that juice was?
He didn't at first, but he had it analyzed,
and they discovered that... of course,
what we know today... that a lot of it
is hydrochloric acid, which is highly corrosive.
Mosley, voice-over: As well as acid,
the juices contained digestive enzymes,
and Beaumont discovered he could break down food
outside the body simply by mixing it with this juice.
Until then, it was widely believed
that digestion was purely mechanical,
but Beaumont showed that the gastric juices
also had a vital role to play.
And this was a big revelation, presumably.
Oh, it was a huge paradigm shift.
I mean, you're going from the mechanical view to the chemical view,
and he was criticized for it back home in America.
He really achieves his fame afterwards
and today, of course, he is known
as the father of gastric physiology.
This is a wonderful, wonderful story, isn't it,
I mean, just an extraordinary story.
It's an extraordinary story and one
that really changed the way we understand the body today.
Mosley, voice-over: I'm going to test the powers of my digestive system
by feeding it a substantial meal
that will really fill my stomach.
Mosley: Ok. Bring on the food.
Hooray!
I have been waiting a long time for this.
Thank you.
So this is the first green thing I've seen for about 3 days.
Mm...
Mosley, voice-over: As the food reaches my stomach,
powerful gastric juices are released.
These juices contain hydrochloric acid
and digestive enzymes...
[Gulp]
Ahh!
Mosley, voice-over: And over the next few hours,
they transform my food.
Mosley: So this is my stomach having eaten,
and the picture is very different
to when it was empty, isn't it?
McAlindon: Yes.
It shows what a fantastic job the stomach can do.
It's really done a blenderizer job here.
I think I saw something
which was probably the beetroot going past,
as well, that sort of red thing.
Oh, there's a great, big leaf, isn't it?
There's a leaf there, so...
and it looks like a bit of beetroot over there
on the top, a bit of pinky stuff.
A bit pinky there. Yeah.
Yes. The leaves will be a lot of fibrous material
which is much more difficult to digest.
So that might stay that way for a little bit longer,
whereas the white bits are probably the chips.
So they are now dissolving in the gastric acid.
So that's more of a mash of stuff.
What happened to the steak, then?
It's interesting that we don't see lumps of meat.
You would think that that would be the case,
but the meat will be broken down
into fibrous material by the action of chewing
and then will be acted on by gastric enzymes
and the gastric acid to such an extent
that you can't actually recognize the meat in the stomach.
You can recognize the plant material
and some of the carbohydrate, the starchy material,
but no lumps of meat there.
Mosley, voice-over: With a big meal of steak and chips inside me,
my stomach has expanded, but by how much?
This big.
No. That's too big.
My fist. Small rugby ball.
Medium-sized melon.
I reckon a good... I think two liters.
Mosley, voice-over: She's right.
The average human stomach can expand
from the size of a small apple when it's empty
to about two liters when full.
That's a fortyfold increase,
and it's now clear that this expandable bag of muscle
has more subtle and powerful ways
to influence how and when we eat
than was ever previously imagined.
Mm.
Mosley, voice-over: Father of 4 Bob Lakhanpal rarely feels full,
no matter what he eats.
Shall I make you one?
No. I don't want salad.
Lakhanpal, voice-over: About 9:00, 10:00,
I have my first breakfast...
couple of toasts, a bowl of corn flakes.
Lunchtime is normally a couple of chapatis
with some chicken or vegetable.
After my lunch if I'm feeling more hungry,
I just get a bowl of corn flakes or weetabix.
In the evening, I get some chips, a burger,
and later on, a chapati.
If I'm feeling a bit peckish,
I buy a big crisp bag
and just munch away.
I just can't get full.
I want to eat everything. Ha ha ha!
Mosley, voice-over: Bob is almost 20 stone,
and being so overweight has had serious consequences.
6 years ago, he had a major health scare.
Lakhanpal, voice-over: I was at home.
I was lying down, and next minute,
I'm getting pain in my jaw and in my arm.
So I thought, "something's wrong.
Let me just drive to the hospital."
So I drove there, and they said, "you're having a heart attack."
I was about 28 at the time,
young, I mean, getting a heart attack.
I was just devastated. Yeah.
Mosley, voice-over: Bob tried going on a diet
but couldn't lose enough weight.
He and his doctors have decided to take more drastic action.
Bob is about to have a gastric bypass operation.
The size of his stomach will be radically reduced.
His doctors expect the operation to have a dramatic effect on his appetite.
For Bob and his family, it's the best hope
of bringing about the health changes that he desperately needs.
Does he come in?
Yeah. Ok.
Take 3 slow deep breaths. At the end of the third one,
things will be much better, drifting gently off to sleep.
Good.
Mosley, voice-over: I'm here at Charing Cross Hospital to watch Bob's surgery.
His surgeon is leading bariatric consultant, Mr Ahmed Ahmed.
All right, John, are we ready to start?
He will operate on Bob using the latest techniques in keyhole surgery.
Ahmed: I've gone through the skin, and the yellow stuff there is fat.
We go through the fat and then through the abdominal wall muscle there.
First quick peek inside, we're gonna see
that all the yellow stuff here you see is fat.
Mosley, voice-over: The first stage of the operation
is to shrink the size of the stomach.
Ahmed: That little pale pink organ coming up and that's your stomach right there.
Mosley: And you're essentially going to reduce the size of that, are you?
Yes, absolutely.
By what sort of amount?
We'll probably make it about 1/10th of its normal size.
10% of what it is at the moment.
Wow, that's quite radical, isn't it?
Yes. The total volume is going to be about 20 mils,
which is about 3 or 4 tablespoons.
So, 90% of the stomach will just be kind of left there inactive, will it?
Exactly.
It's still going to have its blood supply
and it's still gonna make gastric juices but it'll never see food again.
Mosley, voice-over: And surprisingly enough,
it's not just Bob's stomach they are affecting.
Now, you might think that just by reducing the size of the stomach
that's how it's going to sort out Bob's problems,
because smaller stomach, you eat less.
It's sort of straightforward.
But actually the mechanism by which it works is completely different,
and it's only relatively recently that they've discovered
why doing gastric bypass is so effective.
Ahmed: The modern thinking actually is that by making a smaller stomach,
you're actually inducing the changes in various chemical messengers,
which in turn affect hunger levels and fullness levels,
which in turn cause the weight loss.
Mmm.
Mosley, voice-over: So, as well as reducing the size of Bob's stomach,
the point of the operation is to change the levels of certain gut hormones.
These chemical messengers are released by the gut in response to food
and tell the brain when to eat or stop eating.
One of the hormones, ghrelin, makes you feel hungry.
We think that ghrelin is actually being produced
from this part of the stomach up here. Right.
This is called the fundus of the stomach,
and this is where all the cells that produce ghrelin are sort of based.
What we think we're doing is we're actually separating
that part of the stomach completely from ever seeing food.
So the food will never touch those cells that make the ghrelin.
Mosley, voice-over: Once they're isolated,
the ghrelin cells no longer function normally.
Hormone production will be reduced and Bob should feel less hungry.
Extraordinary, isn't it,
that little area of the stomach could be responsible for
how hungry you feel?
Mosley, voice-over: The next stage of the operation
is to re-attach Bob's smaller stomach back to his intestine.
Ok, let go. Thanks.
From now on, it will be right next to the part of his intestine
that produces the gut hormone, pyy, that makes him feel full.
Mosley: How long does food normally take to get there?
At this point, about 20 or 30 minutes, I would imagine.
Right. So instead of taking, say, 20 minutes
for your brain to get the message, "you're full, stop eating",
it might take, what, 5 minutes?
Yeah, around 5 minutes.
Mosley, voice-over: Mr. Ahmed believes the operation
will have an immediate impact on Bob's appetite.
Ahmed: Patients who normally eat 3 or 4 meals throughout a day
eat maybe just 1 or 2 meals after surgery, and when they do eat,
they eat really small portions through, you know, side plates
or children's portions because they just don't feel like eating
the same amounts as they were before, and they're happy.
It's not like something that's imposed on them.
They actually are very satisfied.
[Doctors talking indistinctly]
Mosley, voice-over: What I find really astonishing about this operation
is that the effects are so profound and widespread because, in essence,
what he is doing is he's just sort of making the stomach smaller
and connecting the bits and yet the effect on Bob will be enormous.
We think that the brain rules our decision-making process,
but its pretty clear from this that our stomach has a very, very profound effect
on how we behave.
Mosley, voice-over: 6 weeks after surgery,
Bob is certainly slimmer than he once was.
Bob: Since operation, I have lost 3 stones. I was 20 stones.
Yeah, I've been losing weight and all my clothes are all loose.
Mosley, voice-over: Crucially, Bob's urge to eat lots of fatty foods has gone.
Bob: I had a bite of a burger. I couldn't swallow it.
So I'm keeping to my diet.
I only drink a cup of soup and I'm full.
I'm happy with that and I can stick with that.
Boy: Dad!
It's just great.
Family's happy. I'm happy. Can't wait to lose more weight.
Mosley, voice-over: The camera has now been traveling inside me for over 4 hours.
It's made its way through the acidic and forbidding world of my stomach
and embarked on the longest part of its journey.
The small intestine or small bowel.
Over the next few hours, as it travels along this tube,
my steak and chips will be broken down,
absorbed and transformed into the energy needed to run my body.
As for me, I'm taking it easy.
Ooh, it's amazing how contented you feel after a nice big meal,
also how tired and slothful.
And I suppose it's no surprise. I'm tired.
There's a frenzy of digestion going on inside me.
As I snooze, the tight folds on the wall of the small intestine
are mixing and churning my mushed-up food in a corkscrew motion.
Digestive enzymes from the pancreas and gall bladder flood the area.
These enzymes induce chemical reactions,
which break the food down into nutrients that my body can readily absorb.
The walls of my small intestine look a bit like a Fluffy towel...
And they are there to aid absorption.
So on the folds here, on the folds of the small bowel,
you can see the finger-like projections of the small bowel lining,
which are called villi.
What they do is to increase the surface area of the small bowel hugely.
What sort of surface area are you talking about?
About a tennis court size if you strip it all out. So it's really huge.
There's a huge amount of work that goes on in there.
Mosley, voice-over: And all this work requires a healthy blood supply.
As I'm lying here digesting my steak and chips,
1/3 of my body's blood is being diverted away from my extremities
and towards the action in my guts.
There's certainly active noises down there.
And as this blood rushes through the vessels in the wall of my small intestine,
it's picking up digested nutrients
and transporting them all over my body.
But this could take another 3 or 4 hours,
so there's time for me to get more hands-on with another digestive system.
Ooh, yes. Here we go. Looks great, isn't it?
Mosley, voice-over: Surgeon and gut specialist James Kinross
has brought along the intestine of an animal
that was destined for the food chain.
So, what we have here... this is a pig
from mouth down to the anus at this end here.
Right. So, this is...
Mosley, voice-over: Although we don't look much like pigs on the outside,
their intestines are remarkably similar to ours.
And what you can see is that the gastrointestinal tract
is basically a tube, and it runs literally from your mouth
all the way down to your bottom.
So, what you have is the esophagus at the top end.
We can actually trace all of this bowel the whole way down.
Mosley, voice-over: The walls of the small intestine feel surprisingly delicate,
and they are threaded with tiny capillaries.
And what you'll see is there's a layer of connective tissue.
Oh, yes.
So the bowel has this connective tissue which takes the blood supply.
And you can see the blood supply here.
So when you absorb a meal,
obviously, the nutrition that you take out of it
has to get into the blood supply.
Yes, that's what's happening to me at the moment.
So, let's see how long this is.
Mosley, voice-over: The human small intestine is roughly 4 meters,
the length of this table.
Ok? All right.
A pig's is much longer.
Return journey. Keep going and keep going.
Our intestines absorb about 7 liters of food, fluid,
and gut secretions every day.
But perhaps the most extraordinary thing about the intestine
is that buried deep inside its tissue
is a very thin layer of brain.
When you think about your brain,
normally you think about the thing up there in your skull,
but you actually have a second brain deep down in the gut.
It's made up of cells like neurons, which you also find in your main brain,
and, in fact, there are over 100 million of them...
as many as you would find in the brain of a cat.
Mosley, voice-over: The neurons are spread out in a thin mesh
that extends all the way from the throat to the rectum.
This brain in our gut orchestrates our digestion.
It's also involved in gut pain.
And surprisingly enough, the way we respond to pain seems to be linked to our personality type.
I've got a personality test here which I've got to fill in which could be dangerously revealing.
It says "a number of characteristics here may or may not apply to you,"
and I've got to score between 1 and 5 for each of these particular characteristics
where 1 means disagree strongly and 5 means agree strongly.
So, first up, "is talkative?"
I think I do like talking. I'll give myself a 4.
Agree a little.
"Tends to find fault with others." Nope.
2 on that.
Mosley, voice-over: This test is designed to analyze the broad traits
that make up the human personality.
"Is original." I'm gonna give myself a 5 on that one.
Of these traits, two have been strongly linked to the gut...
being extrovert and being neurotic.
Extroverts tend to be the life and soul of the party,
whereas neurotics are quieter, more anxious, and often put a negative spin on events.
Nope. No, I don't like quarreling.
"Can be tense." Yes, I can be tense... sometimes, sometimes not.
Most people are predominantly one or the other.
I think I'll give myself a 4 on that, 3, 5, 1, 4.
Not overly. So, ok, that's complete.
I'm going to send it off for analysis.
Be interesting to see what they make of it.
Mosley, voice-over: My test will be analyzed at the Wingate Institute in London
by gastroenterologist Dr Adam Farmer.
So what we're trying to do in this study
is to relate personality to pain responses
and then to try and link the two together.
Mosley, voice-over: Adam reckons that my personality
will influence the way the neurons in my gut respond to pain he's about to inflict.
You just rest your arm there.
Just so you're nice and comfortable.
Mosley, voice-over: These findings are important
because they could change the way doctors treat chronic gut pain.
The test involves once again sticking a tube down my nose and into my gullet.
So, once it's down and sat in your gullet round about there,
then we'll inflate the balloon to cause pain.
Oh, God.
Ok, here we go. So slight tickling
at the back of your nose now.
Mosley, voice-over: Adam has found that the guts of extroverts and neurotics
respond to pain in very different ways.
Well, done. So, the tube is down.
You're quite safe now.
[Coughs]
Mosley, voice-over: I may be safe, but I fear the worst is yet to come.
[Coughing]
We're going to give you a series of 7 painful stimuli.
I'm going to inflate the balloon up to your pain tolerance level.
What, really, I mean by that
is to the point where you can't tolerate any more,
where you've had enough.
You ready? I'm ready if you're ready.
I'm just about ready. Begin. Ok.
Ooh, yeah.
Ok.
I'm putting this at 7 to 8. Absolute pain about an 8.
Ugh! Bloody horrible.
Mosley, voice-over: To see how my body responds to pain,
Adam monitors my heart rate and blood pressure.
I'm expecting them both to rise because that's what the text books say.
So the pain is coming now.
Yeoow!
Yeah. I am keen for you to remove this thing now.
See the results.
Mosley, voice-over: If Adam is right, my pain response
will be determined by my personality type.
Your psychological results were extremely interesting.
In terms of what do you feel your personality traits are,
it's often a good suggestion.
Yeah. I think I'm probably inclined towards the neurotic.
People when they meet me they assume I'm more extrovert,
but actually I suspect I'm a neurotic posing as an extrovert.
Absolutely they were very much the results from your personality questionnaires
that out of a possible 100 on the neuroticism scale, you scored 75.
Ok!
Mosley, voice-over: And as a neurotic,
the changes in my heart rate and blood pressure
were exactly what Adam expected.
So we can see that in response to the balloon,
you actually dropped your blood pressure and slowed your heart rate down
for a transient couple of seconds.
I find that really, really surprising, I must admit,
because I would absolutely have expected them to go up.
I've always been taught pain, basically, your heart rate goes up,
your blood pressure goes up, your body doesn't like it.
Mosley, voice-over: It seems, however, that when neurotics are hurt,
the vagus nerve, a nerve that connects your brain to your gut,
becomes more active.
This causes heart rate and blood pressure to drop,
which in turn is believed to have a calming effect, reducing the amount of pain that's felt.
And you don't find that in extroverts?
No, extroverts tend to have the more classic heart rate goes up,
blood pressure goes up.
Mosley, voice-over: For Adam, the results mean that neurotics and extroverts
could be treated for gut pain in very different ways.
For instance, those who have high neuroticism scores,
we would use psychological techniques such as cognitive behavioral therapy
whereas the more extrovert ones,
we may well use pharmaceutical or drug therapy in these patients.
Brilliant, I have to say. I rarely go in for an experiment of some form
where I'm genuinely surprised at the end, but I was
genuinely, genuinely, surprised by this one.
Great, well you were an excellent subject and you did extremely well.
Thank you.
Oh, yeah!
Mosley, voice-over: It's been almost 9 hours since I swallowed the camera
and began life as a museum exhibit.
During that time the camera has traveled over 5 meters through my guts,
but from now things will really slow down
and move along at an even more leisurely pace.
We're at the outer reaches of this alien world... the large intestine or colon.
You can see that the lining of the colon
is very much flatter and whiter than the small bowel.
You can see the little blood vessels running though very, very clearly in the colon.
Very weird, isn't it?
It's a big organ, so you can often see a big hole,
whereas a small bowel is very long but very small in diameter.
Mosley, voice-over: Through the flatter, wider surfaces of the colon,
water is being drawn out from what remains of my food.
You have some slightly more, uh, formed material in there.
Ha ha ha!
That's Mark's polite way of saying that what we're looking at is feces.
But it's not just leftover food.
1/3 of the weight of my feces is actually bacteria.
There are trillions of them, and they form their own mini-ecosystem.
They feed on the food that my small intestine wasn't able to digest,
helpfully breaking it down into nutrients and also making vitamins.
From their dark, dank home in the colon,
these bacteria play a critical role in keeping us healthy.
Most of us don't want to think too hard about feces,
but I'm off to meet a scientist who is absolutely fascinated by it,
and she claims that you can learn an awful lot about somebody
simply by examining their excrement.
Well, I've sent her a sample of my own
and I'm off now to discover just what she has learnt about me.
Mosley, voice-over: Microbiologist Dr Gemma Walton spends her professional life
investigating the different bacteria that colonize our guts.
It's important work, but her research
does give her laboratory a very distinctive odor.
Ooh, God! [Coughing]
Uhh! That is... Hello, Gemma.
Hi. Nice to meet you.
I'm not sure I should shake hands.
That is a truly revolting smell.
It's a lovely lab smell.
It's not a lab smell.
It's the worst bathroom sort of pooey smell.
Mosley, voice-over: Inside these flasks,
Gemma has re-created the conditions found in the human colon.
She uses this to study some of the huge variety of bacteria that live there.
Each of us has our own unique mix of different strains, and Gemma has been looking at mine.
First up, lactobacillus.
So lactobacillus is a big group of bacteria
associated with some quite beneficial effects.
Mosley, voice-over: As well as helping break down food,
lactobacillus excrete acid which fights off other, more harmful bacteria.
So these are good guys?
So, yes, these are your own good guys.
But she's also found some species that don't sound so friendly.
If you have a look at that plate there for me, Michael,
do you see some pink colonies on there? Yes.
Now, those pink colonies are likely to be E. coli.
Right.
E. coli I think of as food poisoning,
infections of the urinary tract.
Well, E. coli are often associated with those events.
However, there are many, many different strains of E. coli,
so it's not necessarily something negative.
In fact, I would be more surprised if I couldn't find any within your sample.
So they're a perfectly normal part of the gut balance.
Ok.
Mosley, voice-over: Gemma reckons I have over a thousand
different strains of bacteria in my feces.
And fortunately I have a healthy mix,
but that balance can become upset, leading to diarrhea and irritable bowels.
If that happens, the good guys may need help.
So there's two ways that you can do that, it's the pre-biotic way.
So the pre-biotic is the food that you eat
that then is a food for your bacteria.
So that can help increase numbers of your beneficial bacteria.
The other way is you can top up the good bacteria
by consuming pro-biotic products
that actually have their own live bacteria in,
and you're introducing them into your gut by consuming them.
Mosley, voice-over: In some cases that's not enough.
[Whirring]
Another lab and more feces,
this time St Mark's hospital in London.
Yes.
Gastroenterologist Dr Ailsa Hart
is working with colleagues from Imperial College
on novel approaches to rebalancing gut bacteria,
the most drastic of which involves performing a fecal transplant.
Hello there. Hello. Michael. Hello.
So, what's happening in here?
Well, we're just in the process of preparing a sample
for a fecal transplant that we're doing as part of a research trial here.
Mosley, voice-over: In this pilot study, feces from a healthy donor
are transplanted into the guts of patients suffering from a condition called pouchitis.
Pouchitis is a form of inflammatory bowel disease,
and normally that's treated very simply with antibiotics,
but in a small group of patients
when the antibiotics haven't worked,
the next line of therapy becomes a little bit trickier,
and it's in that group of patients
that we're going to try this particular technique.
Mosley, voice-over: They are hoping to replace the unhealthy mix of bacteria
in the patient's guts with a healthy mix of someone else's.
First, the donor feces are blended with salt-water...
[Whirring]
And then filtered.
It sounds, I must admit, slightly revolting.
Ha ha ha!
It does sound revolting. It sounds disgusting.
But this is for a group of patients who have had a lot of therapies beforehand,
troubled by lots of diarrhea, awful incontinence,
and really dreadful quality of life, actually.
Mosley, voice-over: The next stage is to put the fecal solution into the patient.
Hart: We take the nasogastric tube.
Down it goes? Down the nose presumably?
Down the nose into the patient's stomach,
and then it's simply the syringe goes onto there and you put it down
into the patient's stomach.
And it just goes straight to the stomach?
And it goes straight into the stomach.
Mosley, voice-over: Dr Hart is looking for signs that this radical approach
will improve her patients' symptoms.
Ooh, very nice.
So, by giving this transplant
are we able to alter the bacteria
in the guts of these patients?
And of course is it having a clinical benefit in them as well?
Mosley, voice-over: It's early days,
and so far only a handful of patients have taken part in the study.
Hart: It's the most densely populated ecosystem on earth,
so to try and understand it is a very tall order.
To try and modulate it, you know, you do ask the question,
are we as human beings clever enough to do this?
[Whirring]
[Horn honking]
Mosley, voice-over: Back at the Science Museum,
my food has been digested and absorbed.
What's left has been chewed over by my gut bacteria
and is now nearing the end of its journey,
but feces are not the only thing that the bacteria in your gut produce.
Flatulence. All of us produce gas.
I guess the question is how much do we produce. Any guesses?
I would say about 7 times a day?
Ooh, 12 to 15?
I haven't farted so far today. Ha ha ha ha!
You farted on the way here in the coach.
No, I didn't.
5 times a day? No.
No, it's a lot more.
It could be ones you don't even notice. You know, involuntary.
Mosley, voice-over: In fact, we're letting out an average of 12 to 15 every day,
typically releasing about two liters of gas.
I was looking to see what he had going on.
Fortunately, according to Gemma, not all of them are smelly.
Well, there's two types of flatulence.
Some people have a very odorous flatulence, and some people less so.
Mosley, voice-over: If you have particularly unpleasant flatulence,
blame the mix of bacteria in your colon.
Some produce pungent hydrogen sulfide gas,
others the less odorous but more flammable methane.
And just as diet can affect the balance of good and bad bacteria,
so it can alter the balance of sulfur to methane producers.
By changing your diet,
you might actually increase the amounts of hydrogen sulfide produced
if you were eating quite a sulfate-rich diet.
Which are the foods that actually produce the worst flatus?
It would be things like beer and wine and breads.
Right.
And vegetables. Vegetables.
Is this is a reason not to eat vegetables?
No, not at all.
Flatus is actually a really, really healthy side effect
of eating fiber in the diet,
so it's something you really want to be doing.
Ha ha ha!
Right, I thought I'd share with you,
this is the essence, if you like,
of really, really horrible flatulence.
It's a sulfide group,
and I thought that you would just be keen to have a little sniff.
[People groaning]
No, thanks. That's fine.
Does anyone recognize the smell?
These are sulfides.
No, not for you?
That's really, really revolting, isn't it?
Mosley, voice-over: Maybe it was the smell that put them off,
but it's late and the science museum is about to close.
The day has certainly been eventful,
and this alien world in my guts is a bit more familiar now.
There's still quite a lot of gunge around there isn't there?
Mosley, voice-over: Time for one more peek at what's going on inside me,
and there's one last question on my mind.
When's the camera going to come out?
I know it will work its way out of my system,
and that could happen sooner rather than later.
I think I need to go urgently to the loo.
I will be back.
I'll see you shortly.
That's good. It might come out yet.
Uhh...
Mmm!
Mosley, voice-over: Over the last 12 hours as I've digested my food,
my guts have been under intense scrutiny.
They've been poked and prodded
in more ways than I could have possibly imagined.
Oh, God. Brings tears your eyes.
Yeahh!
Along the way, I've discovered
that what goes on inside this mess of tubing
not only profoundly affects our health and well-being
but our behavior, too.
My experience as a museum exhibit
has left me with a huge respect for my guts and its inhabitants.
They are working together with an intelligence and complexity
that we're only just beginning to understand.
And as for the camera, it did eventually find its way out,
but that's one part of this process that I'm going to keep private.
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