The Wonderful World of Blood with Michael Mosley

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0:00:05 > 0:00:09Of all the wonders of the human body there's one that I think is

0:00:09 > 0:00:11more mysterious than any other.

0:00:13 > 0:00:16The very sight makes some people faint.

0:00:18 > 0:00:20Losing half will kill you.

0:00:22 > 0:00:25And it permeates our culture as surely as our bodies.

0:00:27 > 0:00:31Blood, it is said, is thicker than water, but what do we really know

0:00:31 > 0:00:36about this sticky red substance and its mysterious, life-giving force?

0:00:38 > 0:00:43For centuries, it's inspired our darkest flights of imagination,

0:00:43 > 0:00:47with the promise that it will help us cheat death, recover our youth.

0:00:49 > 0:00:53But now science is finding new ways to tap its true potential.

0:00:56 > 0:00:57'I'm going to investigate

0:00:57 > 0:01:00'the strange and wonderful world of my own blood.'

0:01:01 > 0:01:04Keep going, keep going, that's it.

0:01:04 > 0:01:07'I'll learn how to boost its power...

0:01:07 > 0:01:09'in the blink of an eye.'

0:01:09 > 0:01:11That is cold!

0:01:13 > 0:01:15'Find out how it tastes.'

0:01:16 > 0:01:19So, here we go, black pudding a la Michael.

0:01:22 > 0:01:25'And chart its many highways and byways.'

0:01:25 > 0:01:27That is my circulation.

0:01:27 > 0:01:31The product of hours spent in the MRI machine.

0:01:31 > 0:01:32'Most surprising of all,

0:01:32 > 0:01:36'I'll discover why Dracula had the right idea.'

0:01:36 > 0:01:39I want to find ways I can meddle with my own blood

0:01:39 > 0:01:42and make myself fitter, younger, healthier.

0:01:43 > 0:01:47I want to show you what blood can really do.

0:01:55 > 0:01:58I'm not fazed by blood, which is just as well

0:01:58 > 0:02:02because in this programme I'm going to spilling lots of it.

0:02:06 > 0:02:09It's quite strange and slightly disturbing watching blood

0:02:09 > 0:02:11flow out of my body, and that's

0:02:11 > 0:02:15because blood is such a precious fluid, in fact almost every great

0:02:15 > 0:02:21religion and society has imbued blood with almost magical qualities.

0:02:25 > 0:02:29I'm making a small withdrawal from my own personal blood bank.

0:02:30 > 0:02:31Around half a litre.

0:02:33 > 0:02:36Enough to get me through a unique set of trials.

0:02:38 > 0:02:43Trials that I hope will reveal five astonishing properties of blood.

0:02:48 > 0:02:52And I'm starting with one that is fundamental to life itself.

0:03:09 > 0:03:13I live and work in London, which is a sprawling city,

0:03:13 > 0:03:17so I like to cycle around, it beats the traffic, it's cheap,

0:03:17 > 0:03:20and it's also good for my heart and lungs.

0:03:22 > 0:03:25Now, I do this mainly in the hope it will keep me fit,

0:03:25 > 0:03:28which these days is something of a uphill struggle.

0:03:28 > 0:03:29The harder I peddle,

0:03:29 > 0:03:33the deeper I breathe, drawing oxygen into my lungs.

0:03:35 > 0:03:37But London traffic aside, there's a limit.

0:03:37 > 0:03:41If I really push myself, my muscles start to ache

0:03:41 > 0:03:44and the reason for that is hidden deep in my blood.

0:03:53 > 0:03:57So what I've got here is two test tubes full of dark, red, rich blood,

0:03:57 > 0:04:00and have a look at what happens to this one

0:04:00 > 0:04:02when I put some oxygen through it.

0:04:08 > 0:04:10It's nice and messy and murky.

0:04:10 > 0:04:15As I bubble oxygen through the blood, something happens.

0:04:15 > 0:04:18So what you should be able to see now is a colour change,

0:04:18 > 0:04:22the one over here is a sort of lighter, brighter, arterial red.

0:04:24 > 0:04:27And this is a clue to a transformation taking place

0:04:27 > 0:04:28inside us.

0:04:29 > 0:04:31In our red blood cells.

0:04:31 > 0:04:34We have staggering numbers of them.

0:04:34 > 0:04:37Your blood contains around 20 trillion,

0:04:37 > 0:04:41and you make 17 million new ones every second.

0:04:42 > 0:04:46Each time we breathe in, they extract oxygen from the air,

0:04:46 > 0:04:49changing colour as they do so.

0:04:51 > 0:04:54And, more importantly, providing life-giving energy.

0:04:56 > 0:04:58But there are limits.

0:05:00 > 0:05:02Now, blood can only hold

0:05:02 > 0:05:06so much oxygen, which is why the colour isn't changing any further.

0:05:07 > 0:05:10No matter how much more oxygen I pump in,

0:05:10 > 0:05:14once each cell is saturated, that's it, my blood can't take

0:05:14 > 0:05:19any more, and this limits what my body is capable of.

0:05:19 > 0:05:24But what if I could change my blood so it carries more oxygen?

0:05:24 > 0:05:27Would that help me cheat my way to greater fitness?

0:05:29 > 0:05:30HE EXHALES

0:05:30 > 0:05:32'To find out, I've come to

0:05:32 > 0:05:35'the Institute of Sport, Exercise and Health.'

0:05:39 > 0:05:40Great effort.

0:05:40 > 0:05:42- HE COUGHS - Lovely!

0:05:42 > 0:05:46'We're going to measure the maximum rate at which my blood can

0:05:46 > 0:05:48'pass oxygen to my muscles.'

0:05:48 > 0:05:50- How does that feel?- OK.

0:05:50 > 0:05:52'It's called my VO2 max.'

0:05:52 > 0:05:54So, you're all set.

0:05:55 > 0:05:56That's it.

0:05:58 > 0:06:00Three minutes of this. That's it, keep going.

0:06:05 > 0:06:06That's excellent.

0:06:10 > 0:06:12Well done, well done.

0:06:12 > 0:06:15'Soon my lungs are burning and my heart is pounding

0:06:15 > 0:06:18'as I struggle to keep the oxygen flowing.'

0:06:18 > 0:06:21That's it, the muscles are working really hard now,

0:06:21 > 0:06:23your heart rate will have increased so the amount of blood being

0:06:23 > 0:06:26pumped around your body per minute is increasing.

0:06:26 > 0:06:28I can see your breathing has increased,

0:06:28 > 0:06:30all of this to just keep

0:06:30 > 0:06:32that supply of oxygen to the muscles

0:06:32 > 0:06:34until the point where you can no longer go on.

0:06:36 > 0:06:42That's excellent. 20 more seconds, come on. That's great.

0:06:42 > 0:06:47Really push it. Keep those legs going round, keep going, keep going.

0:06:47 > 0:06:49That's it. Stop the load.

0:06:49 > 0:06:51That's it, that's it, that's it.

0:06:54 > 0:06:55Whoo!

0:06:57 > 0:06:59Yeah. I think the thing that surprised me most

0:06:59 > 0:07:01was the pain was all in my thigh,

0:07:01 > 0:07:04that was what was really hurting, it wasn't my lungs at all.

0:07:04 > 0:07:07So it's your legs that stopped you, then, yeah, and that's what's common

0:07:07 > 0:07:10with most people, it's the failure of delivery of oxygen to the muscles

0:07:10 > 0:07:12which stops you from cycling any more

0:07:12 > 0:07:13rather than running out of breath.

0:07:13 > 0:07:16So the problem was muscles crying at me I need more oxygen.

0:07:16 > 0:07:18Yeah, combination of how much you can breathe in

0:07:18 > 0:07:21and then how much oxygen you can pump round in your circulation, it

0:07:21 > 0:07:25can no longer meet that demand and that's where everything falls apart.

0:07:25 > 0:07:26Right.

0:07:26 > 0:07:30'Now for my results. Just how fit am I?

0:07:30 > 0:07:32'This could be embarrassing.'

0:07:32 > 0:07:39What we see here is, for your body weight, your VO2 max is...

0:07:39 > 0:07:40Da-dum...

0:07:41 > 0:07:43- ..35 mils per kilo per minute.- OK.

0:07:43 > 0:07:46I'm a little bit disappointed because, three years ago when I

0:07:46 > 0:07:49did this test it was about the same, maybe 35, 36, so...

0:07:49 > 0:07:52I think that's good, then.

0:07:52 > 0:07:53Beyond the age of about 40 or so

0:07:53 > 0:07:58you would expect VO2 max to just slowly decline as you get older

0:07:58 > 0:08:01and older, so, as the years have gone on maybe the training that

0:08:01 > 0:08:05you do is just allowing you to stay in a steady state.

0:08:05 > 0:08:07So, 35. Is that OK for a bloke my age?

0:08:07 > 0:08:09It's absolutely fine.

0:08:09 > 0:08:12'Fine, but not particularly impressive.

0:08:12 > 0:08:15'Although the strength of my heart and lungs limits how hard

0:08:15 > 0:08:18'I can cycle, my red cells also matter.

0:08:20 > 0:08:21'Time to watch them in action.'

0:08:21 > 0:08:23What have we got here. Am I on here?

0:08:23 > 0:08:26You're going to sit down or lie down if you will.

0:08:28 > 0:08:30This is a video microscope,

0:08:30 > 0:08:31so hopefully, touch wood,

0:08:31 > 0:08:33we should be able to see your capillaries under your tongue.

0:08:33 > 0:08:36- OK.- We should be able to see the red blood cells

0:08:36 > 0:08:40flowing through, so tip of tongue on top of your mouth and we'll just try

0:08:40 > 0:08:42and find some blood vessels.

0:08:42 > 0:08:47'Ned's looking for capillaries, the smallest blood vessels in my body.'

0:08:47 > 0:08:49So here we can see the capillaries

0:08:49 > 0:08:52and you can see different size capillaries.

0:08:52 > 0:08:54All the little black dots that you can see are the individual

0:08:54 > 0:08:57red blood cells floating through the capillaries,

0:08:57 > 0:09:01and it's those tiny blood vessels where we see the flow going,

0:09:01 > 0:09:03that is the underlying factor of oxygen delivery.

0:09:05 > 0:09:07It's fascinating to watch.

0:09:07 > 0:09:12They're like tiny bumper cars barging their way the narrow

0:09:12 > 0:09:17streets of my circulation, delivering their cargo of oxygen.

0:09:17 > 0:09:20Doesn't matter what's happening higher up, doesn't matter

0:09:20 > 0:09:23what's happening with your blood pressure, doesn't matter with your

0:09:23 > 0:09:26cardiac output, your heart rate, you need to have that final step,

0:09:26 > 0:09:30an adequate off loading capacity to get the oxygen to your muscles.

0:09:31 > 0:09:34One way to increase your red blood cell count,

0:09:34 > 0:09:38and therefore your athletic performance, is to take drugs.

0:09:38 > 0:09:40This is both dangerous and illegal.

0:09:47 > 0:09:50The alternative is to train at altitude,

0:09:50 > 0:09:54preferably very high altitude.

0:09:54 > 0:09:57Dan and Ned have both spent time on Everest researching how

0:09:57 > 0:09:59altitude affects the human body.

0:10:03 > 0:10:06At this height, there's a lot less oxygen around.

0:10:07 > 0:10:11To compensate, our body makes more red blood cells.

0:10:12 > 0:10:16Fortunately, to get the same results I don't have to go to the Himalayas.

0:10:18 > 0:10:19Pulse oximeter.

0:10:19 > 0:10:20That's perfect...

0:10:20 > 0:10:22'I just have to cross the room.'

0:10:22 > 0:10:24So, put that on your finger, once you go through the door,

0:10:24 > 0:10:27you're going to be in about 12% oxygen, which is

0:10:27 > 0:10:30the equivalent of somewhere around 4,500 metres,

0:10:30 > 0:10:31so about the summit of Mont Blanc.

0:10:35 > 0:10:37OK, smells a bit funny, but otherwise...

0:10:37 > 0:10:39- You're feeling all right, though? - Yeah, yeah.

0:10:39 > 0:10:41Good, excellent.

0:10:43 > 0:10:45This is an altitude chamber.

0:10:47 > 0:10:51I'm going to be trapped inside here for the next four hours.

0:10:51 > 0:10:54So the first thing that will happen to Michael as he goes

0:10:54 > 0:10:56into the chamber, is his body will sense that

0:10:56 > 0:10:58there's a reduced level of oxygen in the air

0:10:58 > 0:11:01and he'll begin to breathe harder and his heart

0:11:01 > 0:11:03will begin to pump faster and harder.

0:11:03 > 0:11:06So that will circulate more oxygen round his body, to try

0:11:06 > 0:11:08and make up for the fact that there's less of it in the air.

0:11:08 > 0:11:11After about an hour,

0:11:11 > 0:11:13I really start to feel the effects.

0:11:20 > 0:11:24My...oxygen levels are around 80%, which is pretty damned low.

0:11:24 > 0:11:26I'm actually feeling very tired,

0:11:26 > 0:11:27I'm doing a lot of yawning at the moment.

0:11:27 > 0:11:29I'm struggling.

0:11:29 > 0:11:32I feel groggy and lethargic.

0:11:32 > 0:11:37But inside me, remarkable changes should already be taking place.

0:11:37 > 0:11:40My body will have detected the fall in oxygen.

0:11:44 > 0:11:46In response, it should have released a hormone called

0:11:46 > 0:11:49erythropoietin, or EPO.

0:11:51 > 0:11:55This hormone triggers the creation of new red blood cells.

0:11:59 > 0:12:01- Right, that's our four hours up. - OK.

0:12:01 > 0:12:04- We can release you from here. - Thank you.

0:12:04 > 0:12:07After four hours spent at the top of Mont Blanc,

0:12:07 > 0:12:09I have my blood tested.

0:12:11 > 0:12:13My EPO levels have shot up

0:12:13 > 0:12:15by an impressive 40%.

0:12:15 > 0:12:19If I'd stayed in the chamber for a bit longer,

0:12:19 > 0:12:21my red blood cells would have started to multiply.

0:12:23 > 0:12:28A drug-free way to boost your blood and enhance your performance.

0:12:28 > 0:12:31No wonder so many athletes train at altitude.

0:12:33 > 0:12:35But there's a catch.

0:12:35 > 0:12:38To make a measurable difference, I'd need to live in this chamber

0:12:38 > 0:12:41for the best part of a month.

0:12:44 > 0:12:47I asked my wife if she fancied keeping me company.

0:12:48 > 0:12:50But strangely enough, she said no.

0:13:00 > 0:13:03So, until she changes her mind, I'm going

0:13:03 > 0:13:06to have to make do with the 20 trillion red cells

0:13:06 > 0:13:09I have at the moment to power me through the streets of London.

0:13:13 > 0:13:17Oxygen, of course, is just the beginning of the story.

0:13:17 > 0:13:20Since ancient times, people have understood that blood is

0:13:20 > 0:13:22a transport system.

0:13:22 > 0:13:26They just had rather peculiar ideas about what was being transported.

0:13:29 > 0:13:32Now, the Romans believed that blood is produced in the liver

0:13:32 > 0:13:36and then spreads throughout the body carrying with it your vital spirits.

0:13:36 > 0:13:39They also thought the blood somehow expressed character.

0:13:39 > 0:13:42This idea still continues in our language.

0:13:42 > 0:13:45We talk about people who are impetuous as being "hot-blooded".

0:13:45 > 0:13:49While people who are emotionless, are, of course, "cold-blooded".

0:13:51 > 0:13:57Apart from oxygen, blood does indeed carry other things.

0:13:57 > 0:14:01Perhaps not vital spirits, but vital nonetheless.

0:14:11 > 0:14:13Fantastic. Looks good.

0:14:13 > 0:14:17'Several times a day, and without giving it a second thought,

0:14:17 > 0:14:20'we load our blood with sugar and fat.'

0:14:27 > 0:14:30Now, this is a sample of blood that was taken from me

0:14:30 > 0:14:32a few hours after eating that greasy breakfast,

0:14:32 > 0:14:37it's been spun down and you can see the red blood cells and other cells

0:14:37 > 0:14:41down here, and this yellowy fluid up here, that is plasma.

0:14:41 > 0:14:45Actually quite murky looking cos it's got little droplets of fat

0:14:45 > 0:14:48in it from my greasy breakfast.

0:14:48 > 0:14:50Now, that's slightly disturbing, isn't it?

0:14:50 > 0:14:54Plasma carries the breakdown of products of food around your body.

0:14:56 > 0:14:59By contrast, this is one that was taken just before I had

0:14:59 > 0:15:03that breakfast and I hope you can see that the plasma is much clearer.

0:15:06 > 0:15:09Plasma makes up more than half our blood

0:15:09 > 0:15:12and is key to its second remarkable ability.

0:15:12 > 0:15:16To absorb the mind boggling variety of substances that

0:15:16 > 0:15:17come from the food we scoff,

0:15:17 > 0:15:22and deliver them as energy to fuel our muscles,

0:15:22 > 0:15:25raw materials to build new tissue,

0:15:25 > 0:15:29or simply to be stored as big rolls of fat around our bodies.

0:15:35 > 0:15:38'But how exactly do the different foods I eat change my blood,

0:15:38 > 0:15:41'and what does that do to me?

0:15:41 > 0:15:43'To find out, the next day I sit down

0:15:43 > 0:15:46'to a very different kind of breakfast.'

0:15:49 > 0:15:52Sadly, no caffeine this morning but I get the orange juice instead.

0:15:54 > 0:15:55Good juice, though.

0:15:58 > 0:16:01I've come to Glasgow University to see how eating

0:16:01 > 0:16:04those different breakfasts has altered my blood, and me.

0:16:07 > 0:16:10Now, this is an impressive piece of kit, isn't it? Wow.

0:16:10 > 0:16:12This is out mass spectrometry room.

0:16:12 > 0:16:16We have six mass spectrometers in here and they function

0:16:16 > 0:16:19like extremely sensitive weighing scales, OK, so you put

0:16:19 > 0:16:22the molecules in, and it weighs each one and lets you know what it is.

0:16:22 > 0:16:24It's processing my blood from breakfast at the moment, is it?

0:16:24 > 0:16:28It is, absolutely, so we've put it in this machine, it's now processing

0:16:28 > 0:16:32it and this is the results that are coming out at the moment.

0:16:32 > 0:16:38This is metabolomics. A novel data crunching approach to food science.

0:16:38 > 0:16:41It is a radically new way to find out what different foods do

0:16:41 > 0:16:43when they get inside you.

0:16:44 > 0:16:47Thousands of different molecules appeared in my blood after

0:16:47 > 0:16:50eating breakfast, and the fascinating part is following how

0:16:50 > 0:16:52they change between the two meals.

0:16:57 > 0:16:58So, what did you find?

0:16:58 > 0:17:01OK, so, we looked in your plasma, we looked at thousands of

0:17:01 > 0:17:05molecules and there are several hundred that are different between

0:17:05 > 0:17:08the two days when you had the different breakfasts.

0:17:08 > 0:17:11Some of them look quite interesting and tell interesting stories

0:17:11 > 0:17:13and I could take you through...

0:17:13 > 0:17:15- Yes, please. - ..some of those.- I'm all ears.

0:17:15 > 0:17:18So first, a pretty obvious one, which is glucose.

0:17:18 > 0:17:23OK, so glucose looks pretty stable and what this means is

0:17:23 > 0:17:26that you are able to control your sugar levels, pretty well.

0:17:26 > 0:17:29That's a relief because I have a family history,

0:17:29 > 0:17:31my father died of diabetes-related illnesses.

0:17:31 > 0:17:33So, although this is not diagnostic, it would indicate

0:17:33 > 0:17:36that your sugar levels are not bouncing about,

0:17:36 > 0:17:39they're keeping fairly stable, and that's true across both breakfasts.

0:17:39 > 0:17:41'Tanita also found something she wasn't expecting,

0:17:41 > 0:17:45'and which she was excited by because she hadn't seen it before.

0:17:45 > 0:17:48'After I ate the greasy fry-up, there was apparently

0:17:48 > 0:17:52'a surge in fatty acids, called prostaglandins.

0:17:52 > 0:17:54'This is a sign of inflammation in my blood vessels

0:17:54 > 0:17:57'and it is not a good thing.'

0:17:57 > 0:18:00If you look at day one, you have a couple of prostaglandins.

0:18:00 > 0:18:03Right, those are both indicators of inflammatory...

0:18:03 > 0:18:05Of inflammation, yeah.

0:18:05 > 0:18:08This could have something to do with the diet that you had on day one,

0:18:08 > 0:18:11so, you know, the fried egg

0:18:11 > 0:18:15and the processed meats somehow inducing inflammation.

0:18:15 > 0:18:18Inflammation is generally a bad thing, isn't it?

0:18:18 > 0:18:20I mean, obviously I would expect the fat to go up,

0:18:20 > 0:18:22but inflammation is also associated with heart disease

0:18:22 > 0:18:25- and all sorts of other bad things, isn't it?- Exactly.

0:18:25 > 0:18:27What I find extraordinary is for the first time by looking

0:18:27 > 0:18:30into blood you can actually tell so much about

0:18:30 > 0:18:32what the food is really doing inside me.

0:18:32 > 0:18:34Yeah, and what you're doing to that food,

0:18:34 > 0:18:37so what you see is a combination of who you are and what you've eaten.

0:18:37 > 0:18:40What is really exciting about metabolomics is

0:18:40 > 0:18:44that by measuring what is going on inside our blood, it is possible to

0:18:44 > 0:18:47see, for the first time, exactly what our food is doing

0:18:47 > 0:18:49after we eat it.

0:18:54 > 0:18:56We are, quite literally, what we eat,

0:18:56 > 0:18:59and our blood's ability to carry such a vast range

0:18:59 > 0:19:04of substances gives it another quality that's often overlooked.

0:19:07 > 0:19:09It's nutritious.

0:19:09 > 0:19:13Across the natural world, there are numerous species of animals

0:19:13 > 0:19:15that feast on human blood.

0:19:20 > 0:19:21Head lice.

0:19:23 > 0:19:24Mosquitoes.

0:19:26 > 0:19:29Leeches.

0:19:29 > 0:19:31In fact, all that lot have at one time or another,

0:19:31 > 0:19:35gorged on my blood, and seem to have enjoyed the experience.

0:19:42 > 0:19:45Even humans sometimes drink blood.

0:19:47 > 0:19:50Now, we're all familiar with the vampire myth,

0:19:50 > 0:19:52but I was surprised to read that in Roman times,

0:19:52 > 0:19:55drinking other people's blood was extremely popular.

0:19:55 > 0:19:57What people would do is they'd go to a fight,

0:19:57 > 0:20:00gladiator lying dead there, and if you had some

0:20:00 > 0:20:03ailment like epilepsy, you would dash in and try and grab

0:20:03 > 0:20:06a chunk of the dead gladiator's liver,

0:20:06 > 0:20:08or perhaps just lick the wounds.

0:20:08 > 0:20:11In fact, the reason people did this is because the gladiators

0:20:11 > 0:20:14were young, they were fit and they were recently dead.

0:20:16 > 0:20:21These days, we're less inclined to drink blood to cure our ailments,

0:20:21 > 0:20:23but we do enjoy eating it.

0:20:28 > 0:20:33Almost every national cuisine has a recipe involving animal blood.

0:20:34 > 0:20:38In a playful, ghoulish mood, I've decided to make a traditional

0:20:38 > 0:20:42British blood dish, with a less traditional ingredient.

0:20:42 > 0:20:43My own blood.

0:20:46 > 0:20:47Here we go.

0:20:47 > 0:20:49Not very attractive looking,

0:20:49 > 0:20:51but I've managed to get two black puddings

0:20:51 > 0:20:54out of 330 mils of my blood.

0:20:54 > 0:20:55This should be

0:20:55 > 0:21:00actually quite nutritious, plenty of protein, lots of vitamin C and iron.

0:21:07 > 0:21:08SIZZLING

0:21:13 > 0:21:16Right, for those who are watching their figures you might

0:21:16 > 0:21:20like to know that blood is really quite calorific. In fact, there's

0:21:20 > 0:21:24almost twice as many calories per mil of blood as, say, beer.

0:21:24 > 0:21:27OK, it's kind of ready to plate up, I think.

0:21:29 > 0:21:31Here we go.

0:21:31 > 0:21:32Black pudding a la Michael.

0:21:36 > 0:21:40Mm, not bad, could do with a bit more salt, I think,

0:21:40 > 0:21:42I obviously don't have very salty blood.

0:21:44 > 0:21:47I don't think it's going to take off as a national dish, this.

0:21:51 > 0:21:52Quite chewy.

0:21:55 > 0:21:58We've seen that one of blood's primary jobs is to carry oxygen

0:21:58 > 0:22:01and nutrients to every part of the body.

0:22:02 > 0:22:06It does so via arteries, veins and capillaries.

0:22:06 > 0:22:08And, of course, it circulates.

0:22:08 > 0:22:11These days the idea that blood circulates

0:22:11 > 0:22:14is as obvious as the fact the earth goes round the sun.

0:22:16 > 0:22:18But it's a surprisingly recent discovery.

0:22:23 > 0:22:26The Romans, believers in vital spirits, were also convinced

0:22:26 > 0:22:31that blood is made fresh every day and travels only one way,

0:22:31 > 0:22:35out to our fingers and toes, where it is burnt away.

0:22:35 > 0:22:37It sounds bizarre to us today,

0:22:37 > 0:22:42but this idea survived largely unchallenged for over 1,000 years,

0:22:42 > 0:22:46until someone decided to do a rather obvious experiment.

0:22:52 > 0:22:56Now, our modern understanding of the human circulatory system began

0:22:56 > 0:23:00here in Bart's Hospital in the early years of the 17th century.

0:23:01 > 0:23:02It began with William Harvey,

0:23:02 > 0:23:06an eminent doctor and most unlikely revolutionary.

0:23:08 > 0:23:11It occurred to Harvey that replenishing our blood

0:23:11 > 0:23:14every day must involve making huge amounts of the red stuff.

0:23:16 > 0:23:19So he decided to do an experiment.

0:23:20 > 0:23:22He got hold of an animal heart.

0:23:24 > 0:23:26He filled one of the chambers with water.

0:23:29 > 0:23:33And then he just kind of poured it out and he measured what he'd got.

0:23:33 > 0:23:36Then he did the calculation.

0:23:36 > 0:23:38He took the volume of water he'd measured

0:23:38 > 0:23:42and multiplied it by the number of times the heart beats.

0:23:42 > 0:23:45This came to around ten litres of blood passing through

0:23:45 > 0:23:47the heart every hour.

0:23:47 > 0:23:50That's 240 litres of blood being

0:23:50 > 0:23:53produced by your body every single day.

0:23:53 > 0:23:57Now, clearly, it was vastly more blood than anyone's body could

0:23:57 > 0:23:58possibly be making in a day.

0:23:58 > 0:24:03The only rational explanation is that blood must be circulating.

0:24:06 > 0:24:10Challenging long-held beliefs was not a good career move,

0:24:10 > 0:24:14so Harvey sat on his discovery for 12 long years.

0:24:17 > 0:24:20It wasn't until 1628 that he laid out his case in

0:24:20 > 0:24:26his masterpiece, De Motu Cordis - On The Motion Of The Heart And Blood.

0:24:30 > 0:24:32A rare copy is kept under lock and key

0:24:32 > 0:24:35at the Hunterian Museum in Glasgow.

0:24:37 > 0:24:40Now, this book only contains one diagram

0:24:40 > 0:24:42but it is an incredibly important diagram because it shows you

0:24:42 > 0:24:47one of Harvey's classic experiments, and I'm about to re-enact it.

0:24:47 > 0:24:49I've got my tourniquet on over here,

0:24:49 > 0:24:51I've also got a safety razor blade which he doesn't mention,

0:24:51 > 0:24:54but which is useful for clearing away a few hairs.

0:24:54 > 0:24:58Now, can you see here, there's a vein there?

0:24:58 > 0:25:00Make it stand up a bit.

0:25:00 > 0:25:04First I block the blood flow by placing my finger over the vein.

0:25:04 > 0:25:09If I drain away the blood above the blockage, the vein stays empty.

0:25:10 > 0:25:13But if I try and drain away blood below the blockage

0:25:13 > 0:25:14it quickly refills.

0:25:15 > 0:25:18There can only be one reason for this.

0:25:18 > 0:25:23Blood is travelling via the veins, back up my arm, towards my heart.

0:25:23 > 0:25:26This is not the world's most exciting experiment to look at

0:25:26 > 0:25:30but it would in time overthrow 1,000 years of dogma

0:25:30 > 0:25:34and also help launch experimental science in Europe.

0:25:38 > 0:25:42Fast forward 400 years and we can now see how blood

0:25:42 > 0:25:46flows through the body in ways Harvey could never have dreamt of.

0:25:49 > 0:25:53Now, this is an MRI machine, and I absolutely loathe MRI machines

0:25:53 > 0:25:56because I'm mildly claustrophobic.

0:25:56 > 0:25:59Apparently, I'm going to be in there for almost four hours.

0:26:04 > 0:26:0530 seconds.

0:26:07 > 0:26:11This powerful scanner is building up a picture of all the major

0:26:11 > 0:26:12blood vessels in my body.

0:26:14 > 0:26:18OK, Michael, can you breathe in, please? Good. Breathe out.

0:26:25 > 0:26:28Now, that is impressive. It's not the sort of thing you would

0:26:28 > 0:26:29normally ever see.

0:26:29 > 0:26:34This is my circulation based on hours spent in the MRI machine,

0:26:34 > 0:26:38it is the major highway down which my blood travels.

0:26:38 > 0:26:41What you're looking at at the moment is actually the arteries,

0:26:41 > 0:26:42the high-speed network.

0:26:43 > 0:26:46If you add in the minor arteries

0:26:46 > 0:26:50and the veins then it gets really complicated.

0:26:50 > 0:26:54Introduce the capillaries and it's almost a sold sculpture of my body,

0:26:54 > 0:26:58in fact blood is so essential, every living cell in my body

0:26:58 > 0:27:03lies on average just a hundredth of a millimetre from a blood vessel.

0:27:03 > 0:27:07Now, that adds up to an astonishing 60,000 miles of tubing.

0:27:07 > 0:27:10Enough to go round the world twice.

0:27:15 > 0:27:19It looks like a vast and complex bit of plumbing,

0:27:19 > 0:27:23and until recently doctors tended to treat it as nothing more

0:27:23 > 0:27:25sophisticated than that.

0:27:25 > 0:27:29But there is actually a secret about our circulatory system

0:27:29 > 0:27:31that we are only now beginning to unravel.

0:27:33 > 0:27:36If an artery supplying the heart gets blocked, then the surgeon

0:27:36 > 0:27:40may try using a vein to bypass the blockage.

0:27:40 > 0:27:45In time, however, the veins themselves often clog. Why?

0:27:54 > 0:27:56Well, the answer came not from medicine

0:27:56 > 0:27:58but from aerodynamic engineering.

0:28:01 > 0:28:05Here at Imperial College in London, engineers spend their days

0:28:05 > 0:28:09analysing how air flows over racing cars and aeroplane wings.

0:28:13 > 0:28:16The team are now applying the techniques of aerodynamics to

0:28:16 > 0:28:20study how blood flows through arteries and veins.

0:28:20 > 0:28:23Peter Vincent has set up a demonstration of what can

0:28:23 > 0:28:26go wrong in a common procedure -

0:28:26 > 0:28:27bypass surgery.

0:28:29 > 0:28:31So what am I looking at here,

0:28:31 > 0:28:32this presumably represents an artery?

0:28:32 > 0:28:36Yep, right's right and this represents a vein

0:28:36 > 0:28:38and the entire configuration represents

0:28:38 > 0:28:40something that would be formed by a clinician

0:28:40 > 0:28:43artificially inside the body, such as a bypass graft.

0:28:43 > 0:28:47OK, so I'm a surgeon, there's a problem further down there,

0:28:47 > 0:28:51I, for example, have attached a vein here to bypass a blockage,

0:28:51 > 0:28:53in, say, an artery feeding the heart.

0:28:53 > 0:28:56Exactly. Yep. That's exactly what it represents.

0:28:56 > 0:29:00'Now we're going to use coloured ink to simulate what happens

0:29:00 > 0:29:03'when our blood tries to flow round a sharp corner.'

0:29:12 > 0:29:15So we can see the ink coming through here, which gives us

0:29:15 > 0:29:16an indication of the flow,

0:29:16 > 0:29:20and what we notice is in this region the flow is very unsteady.

0:29:22 > 0:29:27Surgeons commonly need to join blood vessels, and it turns out that

0:29:27 > 0:29:31if the angle of connection is too extreme it creates

0:29:31 > 0:29:32turmoil in our blood flow.

0:29:38 > 0:29:39The problem with this is,

0:29:39 > 0:29:43highly unsteady flow can actually aggravate the vessel wall and cause

0:29:43 > 0:29:47the vessel wall to inflame, and grow inwards and block this connection,

0:29:47 > 0:29:51which is clearly very bad if you've formed a bypass graft.

0:29:51 > 0:29:54Right, so that causes the inside of the artery to fur up or block

0:29:54 > 0:29:56or whatever, is that right?

0:29:56 > 0:29:58To inflame inwards, it's an inflammatory response,

0:29:58 > 0:30:02so the idea is, if we understand the flow patterns in more detail,

0:30:02 > 0:30:06we can look to suppress the unsteadiness that occurs and try

0:30:06 > 0:30:11and create bypasses that are, well, function for longer and last longer.

0:30:12 > 0:30:17Now. Watch what happens when our tube is curved instead of straight.

0:30:17 > 0:30:21With a gentler angle of connection, the flow becomes

0:30:21 > 0:30:23much, much smoother.

0:30:25 > 0:30:28Peter's team are exploring how the intricate curves of our blood

0:30:28 > 0:30:33vessels affect the way our blood flows throughout our whole body.

0:30:35 > 0:30:40What we can do is zoom in on the flow field on the fluid dynamics.

0:30:40 > 0:30:43'They've been looking at how blood moves through the aorta,

0:30:43 > 0:30:46'the main artery coming out of the heart.'

0:30:46 > 0:30:51In the aortic arch, for example, you can see the natural twist

0:30:51 > 0:30:53and curvature of the arch,

0:30:53 > 0:30:55so as well as just curving around it twists and it sort of has

0:30:55 > 0:31:00a helical shape, that acts to mix and swirl the blood, mix oxygen

0:31:00 > 0:31:04in the blood, helps to stabilise the flow, avoid unsteadiness.

0:31:04 > 0:31:06It just makes you fully appreciate

0:31:06 > 0:31:08the wonders of evolution, doesn't it?

0:31:08 > 0:31:10Well, yes, quite, absolutely, yeah.

0:31:11 > 0:31:15So the subtle curves and shapes of our arteries aren't random.

0:31:15 > 0:31:19Our circulatory system is a real wonder of natural engineering,

0:31:19 > 0:31:22designed to control our blood flow with amazing precision.

0:31:24 > 0:31:27And this research has inspired a very neat medical innovation.

0:31:32 > 0:31:36Now, this is something called a stent, it's a nickel-titanium mesh

0:31:36 > 0:31:40and what surgeons do is they use it in arteries which are partially

0:31:40 > 0:31:44blocked, might be an artery feeding your heart or, say, your leg, and it

0:31:44 > 0:31:48holds that artery open. The trouble is, that they get blocked up and it

0:31:48 > 0:31:51turns out that part of the problem is because they are straight.

0:31:51 > 0:31:56Now, this is a stent of very recent invention, if you like,

0:31:56 > 0:31:58invented by a scientist here at Imperial,

0:31:58 > 0:32:01and, as I hope you can see, it is actually a helix.

0:32:01 > 0:32:02Now, it looks really simple,

0:32:02 > 0:32:06but this is the product of 20 years research and recent

0:32:06 > 0:32:11studies in humans suggest that this survives better in the body,

0:32:11 > 0:32:14if you like, it's less likely to block up and fail

0:32:14 > 0:32:16than a standard stent.

0:32:16 > 0:32:18Beautiful piece of engineering.

0:32:19 > 0:32:23Our circulatory system enables our blood to reach every organ

0:32:23 > 0:32:25and every living cell in our body,

0:32:25 > 0:32:29carrying its vital supplies of oxygen and food.

0:32:30 > 0:32:34But it also allows our blood to do something just as important,

0:32:34 > 0:32:35defend us.

0:32:46 > 0:32:48I'm going to try and demonstrate what happens when your body

0:32:48 > 0:32:51is injured or under attack, using a nice sharp needle which

0:32:51 > 0:32:53I'm going to scratch myself with,

0:32:53 > 0:32:55and this machine here, what it will

0:32:55 > 0:32:59do is record the blood flow, just beneath the surface of the skin.

0:32:59 > 0:33:03At the moment it's just looking sort of blue,

0:33:03 > 0:33:05which suggests that nothing very exciting is going on.

0:33:05 > 0:33:06Scratch there.

0:33:09 > 0:33:11Oh, I was a bit enthusiastic there.

0:33:12 > 0:33:17Immediately you can start to see the reaction, there is a huge increase

0:33:17 > 0:33:20in blood flow to that area which is demonstrated by the sort of area of

0:33:20 > 0:33:25red and orange, and what you've got is a classic inflammatory response.

0:33:25 > 0:33:27My blood is rushing to the area under attack.

0:33:29 > 0:33:33Now, the body's first reaction to any infection or injury is to

0:33:33 > 0:33:37increase blood flow, bringing heat, swelling, redness and pain.

0:33:39 > 0:33:43Today, we know inflammation is a normal response to injury

0:33:43 > 0:33:44but this wasn't always the case.

0:33:46 > 0:33:48For thousands of years, these symptoms were

0:33:48 > 0:33:53seen as a sign that the blood was overheating, expanding.

0:33:53 > 0:33:56The obvious answer was to let it escape. Bloodletting.

0:33:59 > 0:34:02Gallons of blood flowed from the veins of victims

0:34:02 > 0:34:03in search of relief.

0:34:03 > 0:34:07Bloodletting was the most common medical practice for nearly

0:34:07 > 0:34:082,000 years.

0:34:08 > 0:34:11So common you could have it done on the high street.

0:34:13 > 0:34:15In medieval times, the person who cut your hair

0:34:15 > 0:34:18and gave you a shave also did the bloodletting.

0:34:18 > 0:34:21The reason you've got these barber poles is because the white

0:34:21 > 0:34:26represents fresh clean bandages, and the red represents blood.

0:34:26 > 0:34:30Originally, you'd have had a basin on top to hold the leeches

0:34:30 > 0:34:32and one underneath to hold the blood.

0:34:35 > 0:34:38Bloodletting may have been beneficial in a few cases,

0:34:38 > 0:34:41but it certainly killed far more than it cured.

0:34:45 > 0:34:49Ironically, draining overheated blood from a patient

0:34:49 > 0:34:51deprived them of critical infection fighters.

0:34:53 > 0:34:55White blood cells.

0:34:57 > 0:35:00A healthy adult has about 40 billion of them.

0:35:01 > 0:35:05They're the front-line defence force of our immune system.

0:35:05 > 0:35:09Constantly battling invading microbes, such as bacteria,

0:35:09 > 0:35:11viruses and fungi.

0:35:12 > 0:35:15Magnified 1,000 times, the larger cells here are

0:35:15 > 0:35:20my own white blood cells, swallowing little green aliens.

0:35:25 > 0:35:29But the immune system is more than just a reactive defensive force,

0:35:29 > 0:35:32a microscopic Dad's Army.

0:35:32 > 0:35:34It can do something much more interesting.

0:35:38 > 0:35:40To show you what it's capable of,

0:35:40 > 0:35:44I'm about to try something that's a first for me.

0:35:44 > 0:35:45White water canoeing.

0:35:53 > 0:35:56The thing about your immune system is it is not only really good

0:35:56 > 0:36:00at responding to danger but also at anticipating danger,

0:36:00 > 0:36:04and I'm about to give it something serious to think about.

0:36:04 > 0:36:06Not really looking forward to it.

0:36:13 > 0:36:15'To activate the response I'm hoping to see,

0:36:15 > 0:36:18'I need to do something that is stressful.'

0:36:22 > 0:36:23Oh, that's cold!

0:36:24 > 0:36:27'Not just physically stressful, but mentally.

0:36:27 > 0:36:31'The aim is to induce a lot of stress but not actually get hurt.'

0:36:44 > 0:36:45And just once.

0:36:45 > 0:36:49Immunologist Doctor Natalie Riddell, from University College London,

0:36:49 > 0:36:52takes generous amounts of my blood.

0:36:52 > 0:36:56Right, probably have to put quite a bit of pressure on there.

0:36:56 > 0:36:57I will, yeah.

0:37:00 > 0:37:01While I warm up,

0:37:01 > 0:37:05Natalie extracts the immune cells from my blood samples.

0:37:05 > 0:37:09The cells that mobilise during the stress response tend to have

0:37:09 > 0:37:14a more kind of aged characteristic, so generally as people get older

0:37:14 > 0:37:17you see more of these age cells. You have very few of these, aged cells.

0:37:17 > 0:37:19- Hurray.- And seem to have quite

0:37:19 > 0:37:20a young immune system.

0:37:20 > 0:37:22- A young immune system. - A young immune system.

0:37:22 > 0:37:24- And that's good, is it? - It is good.

0:37:24 > 0:37:25OK, so what happened?

0:37:25 > 0:37:29So here, we're looking at cells called a natural killer cell

0:37:29 > 0:37:33and these cells are known to respond during psychological stress

0:37:33 > 0:37:35or physical stress.

0:37:35 > 0:37:39This is your baseline, so we can see we've got quite a low level.

0:37:39 > 0:37:43Right, OK. That's not bad, doubling.

0:37:43 > 0:37:45As you can see the peak has gone up.

0:37:45 > 0:37:47'Now, that's impressive.

0:37:47 > 0:37:51'Ten minutes of challenging canoeing was all it took to trigger

0:37:51 > 0:37:54'a 50% increase in the proportion of natural killer cells

0:37:54 > 0:37:56'in my blood stream.'

0:38:03 > 0:38:05My body clearly decided after I'd jumped in the cold water,

0:38:05 > 0:38:07there was a good chance I would get hurt

0:38:07 > 0:38:10and primed my immune system for action.

0:38:11 > 0:38:15During a stress response, not only is your cardiovascular system

0:38:15 > 0:38:19activated and your energy stores are mobilised

0:38:19 > 0:38:22so that you have the energy to escape whatever the threat is,

0:38:22 > 0:38:25also your immune system is mobilised.

0:38:25 > 0:38:29It's very smart, isn't it, because I kind of hadn't appreciated

0:38:29 > 0:38:31the extent to which it anticipated threat.

0:38:31 > 0:38:34I mean, it kind of obviously noticed that something odd was going on.

0:38:34 > 0:38:36Is going to happen.

0:38:36 > 0:38:39And it knew, if you like, that there was something

0:38:39 > 0:38:41odd going on so it mobilised ready to take on.

0:38:41 > 0:38:45It mobilises ready, poised, just in case, there is some

0:38:45 > 0:38:48kind of injury and infection or invading organism.

0:38:52 > 0:38:56Well, it's very nice to be told I've got a young immune system,

0:38:56 > 0:38:59but I was really impressed by the way that my natural killer cells

0:38:59 > 0:39:03sprang into action so incredibly rapidly, and it

0:39:03 > 0:39:07has to be rapid because we are constantly surrounded by threats.

0:39:11 > 0:39:14Our blood moves surprisingly fast.

0:39:16 > 0:39:19The average cell does a round trip from our heart

0:39:19 > 0:39:21to our extremities once every minute.

0:39:26 > 0:39:29But this also means that if I cut myself blood can rapidly escape.

0:39:32 > 0:39:35If nothing stopped it, I'd soon be in serious trouble.

0:39:37 > 0:39:40A simple cut, and a short while later

0:39:40 > 0:39:43up to five litres of blood would have drained away.

0:39:46 > 0:39:50Fortunately, our bodies contain some really sophisticated mechanisms

0:39:50 > 0:39:52for making sure that doesn't happen.

0:40:02 > 0:40:07As soon as blood leaves the body, something extraordinary happens.

0:40:07 > 0:40:10This is the fifth key property of our blood,

0:40:10 > 0:40:13and in many ways, the most impressive.

0:40:15 > 0:40:18So this is a vial of fresh human blood.

0:40:18 > 0:40:22If I take the top off, and leave it, something interesting should happen.

0:40:25 > 0:40:26You may not see

0:40:26 > 0:40:29a particularly impressive change

0:40:29 > 0:40:31but this blood has been transformed.

0:40:39 > 0:40:40If I tilt it, nothing comes out.

0:40:48 > 0:40:50That is a real clot,

0:40:50 > 0:40:54the product in a series of complicated chemical reactions.

0:40:55 > 0:40:59What's happening inside the blood is a minor marvel of evolution.

0:41:01 > 0:41:08Looking at the clot magnified 5,000 times, it is a thing of beauty.

0:41:09 > 0:41:13You can probably see the red cells and the white cells trapped

0:41:13 > 0:41:18in the matrix, and at the heart of it all is a very special cell.

0:41:20 > 0:41:22To find out more, I've come to

0:41:22 > 0:41:26the William Harvey Research Institute in London,

0:41:26 > 0:41:29where yet more blood is taken to isolate the cells

0:41:29 > 0:41:30I'm particularly interested in.

0:41:32 > 0:41:34The platelets.

0:41:34 > 0:41:37The great thing about platelets is they're almost that forgotten

0:41:37 > 0:41:39blood cell going round all the time in the background,

0:41:39 > 0:41:41probably don't think about them too much, but,

0:41:41 > 0:41:42should your blood vessel break,

0:41:42 > 0:41:46should you start bleeding they're going to spring into action

0:41:46 > 0:41:49and start to block up that hole and stop the blood

0:41:49 > 0:41:51coming out of your blood vessels, so they're really important.

0:41:53 > 0:41:56To see them in action, my sample is set to flow through a tube

0:41:56 > 0:42:00that mimics a broken blood vessel, just like a cut on our body.

0:42:01 > 0:42:03- Hi there.- Hello.

0:42:05 > 0:42:06OK, thank you.

0:42:06 > 0:42:11'What I'm looking at is the first steps in the creation of a clot.'

0:42:11 > 0:42:14Rather beautiful, aren't they? Little platelets.

0:42:16 > 0:42:20This is the first time I've seen these tiny cells in action.

0:42:21 > 0:42:25First, individual cells, those tiny green dots, start to stick.

0:42:26 > 0:42:29Never seen them activate like this before.

0:42:31 > 0:42:33They signal others to join in.

0:42:34 > 0:42:38Within minutes, clumps of cells have stuck together, forming a clot.

0:42:40 > 0:42:44In our body, this process begins the instant we're cut.

0:42:44 > 0:42:47On the arterial side you need it to be quick, cos the blood's high

0:42:47 > 0:42:50pressure and everything's moving fast, you need it to block up.

0:42:50 > 0:42:52In your circulation your blood goes round once every minute,

0:42:52 > 0:42:57so your whole blood volumes going round every minute so the arterial side needs to respond quickly....

0:42:57 > 0:43:00- You've got a bleed, you're going to bleed to death...- You're going to bleed very quickly.

0:43:00 > 0:43:03Now you can see they've formed all these nice clusters of platelets

0:43:03 > 0:43:06where they've all become activated, and will block up the holes.

0:43:08 > 0:43:13Magnified 10,000 times, the platelets look like spiky balls.

0:43:14 > 0:43:19When they activate, they grow these sticky fingers to cling together.

0:43:20 > 0:43:24But the platelets can't stem the blood flow all by themselves.

0:43:25 > 0:43:29There's another vital reaction needed to stop us bleeding to death.

0:43:30 > 0:43:34And with the help of one of the deadliest animals on earth,

0:43:34 > 0:43:37I should be able to show you this process happening.

0:43:40 > 0:43:44Now, I've got some fresh human blood here and I've also got

0:43:44 > 0:43:47some snake venom, this is actually from a fer-de-lance, which is

0:43:47 > 0:43:49a South American viper.

0:43:54 > 0:43:55OK, in we go.

0:43:57 > 0:43:59Give it a bit of a swirl.

0:44:00 > 0:44:05Within seconds, the venom has drastically altered my blood.

0:44:05 > 0:44:08I think that's definitely becoming thicker and murkier, I'm actually

0:44:08 > 0:44:12quite surprised that worked, with quite a small amount of venom.

0:44:12 > 0:44:13Let's see what happens if I pour it in here.

0:44:16 > 0:44:21You can see it kind of comes out, more in sort of globby bits, that

0:44:21 > 0:44:26have kind of solidified and turned almost into a jelly-like substance.

0:44:26 > 0:44:29Just imagine how much damage that would do.

0:44:29 > 0:44:34The viper venom is mimicking what happens inside a cut blood vessel.

0:44:35 > 0:44:39Long strands of protein are forming, thickening the liquid.

0:44:42 > 0:44:45When we're cut, this same process works to our advantage,

0:44:45 > 0:44:47creating a web for the platelets to stick to.

0:44:49 > 0:44:53Without this emergency response, we would bleed to death,

0:44:53 > 0:44:55every time we have a little cut.

0:44:57 > 0:44:59But there's more to it than that.

0:44:59 > 0:45:01Research by the military and others

0:45:01 > 0:45:05has pointed towards unexpected healing properties in blood.

0:45:12 > 0:45:16'I don't often find myself in a Kensington beauty clinic,

0:45:16 > 0:45:19'but I want to test out a new treatment.'

0:45:19 > 0:45:21I've come to have some blood taken.

0:45:22 > 0:45:26'Sometimes called the vampire face-lift,

0:45:26 > 0:45:28'PRP, platelet-rich plasma therapy,

0:45:28 > 0:45:32'claims to accelerate healing and reverse the signs of ageing.

0:45:35 > 0:45:38'First my blood is treated to make a concentrated

0:45:38 > 0:45:40'solution of platelets in plasma.

0:45:40 > 0:45:44'Next, this is injected directly into my face.'

0:45:47 > 0:45:49It's actually very satisfying, isn't it,

0:45:49 > 0:45:52the idea that all you're really doing is, you're not injecting

0:45:52 > 0:45:56an alien drug or anything, you're just taking your own stuff, spinning

0:45:56 > 0:45:59it down and then sticking it back into you, the power of blood.

0:46:01 > 0:46:04Indeed, it's the elegance and simplicity

0:46:04 > 0:46:07because it's the power of your own healing.

0:46:07 > 0:46:11In theory, activated platelets and growth factors will trigger

0:46:11 > 0:46:15a healing response in my skin, smoothing out wrinkles.

0:46:15 > 0:46:17Why does this work,

0:46:17 > 0:46:20when what you're effectively doing is just sticking blood back into

0:46:20 > 0:46:25my face and presumably the arteries in my face are doing that anyway?

0:46:25 > 0:46:29Well, two aspects, one, when you actually squeeze

0:46:29 > 0:46:33the platelet-rich plasma into that area it then ignites those platelets

0:46:33 > 0:46:39to open, plus you also are stimulating the area by wounding it.

0:46:39 > 0:46:42Right, so I'll get a certain puffiness, a certain bruising...

0:46:42 > 0:46:43You will, you will.

0:46:43 > 0:46:45But that's part of the therapeutic process.

0:46:45 > 0:46:46Indeed.

0:46:46 > 0:46:50What would I expect to see in a few weeks' or months' time?

0:46:50 > 0:46:52You'll feel a difference in the tone and texture

0:46:52 > 0:46:56of your skin, hopefully become more like a baby's bum.

0:46:56 > 0:46:58MICHAEL LAUGHS

0:47:02 > 0:47:05I expect my face is still a bit inflamed

0:47:05 > 0:47:08and blotchy as all those enriched platelets

0:47:08 > 0:47:11and plasma run around inside my skin doing their magic.

0:47:11 > 0:47:13I'm told that will go very quickly,

0:47:13 > 0:47:17with two weeks I should see some improvement and within

0:47:17 > 0:47:20a couple of months, apparently my skin is going to feel

0:47:20 > 0:47:22like a baby's bottom. I look forward to it.

0:47:34 > 0:47:38Now, it's been a couple of weeks since I had the platelet-rich plasma

0:47:38 > 0:47:41injected into my face, and I think my skin is perhaps

0:47:41 > 0:47:44a little bit smoother, though you'd have to have a look

0:47:44 > 0:47:47at the before and after photographs and make your own judgment.

0:47:49 > 0:47:51Call it wishful thinking, but perhaps

0:47:51 > 0:47:53there's a bit of improvement.

0:48:00 > 0:48:04The so-called vampire facial is part of a long tradition ascribing

0:48:04 > 0:48:06extraordinary healing powers to blood.

0:48:08 > 0:48:11For centuries, there have been gruesome tales of blood being

0:48:11 > 0:48:14used to cure the sick and rejuvenate the old.

0:48:18 > 0:48:22A 16th century Hungarian countess, Elizabeth Bathory,

0:48:22 > 0:48:26believed by many to be the most prolific female murderer in history,

0:48:26 > 0:48:29is said to have bathed in the blood of her slaughtered victims.

0:48:31 > 0:48:34Legend has it she hoped that the fresh blood would help

0:48:34 > 0:48:37her cling to her own fading beauty.

0:48:39 > 0:48:42These stories and legends inspired one of the great Gothic novels

0:48:42 > 0:48:46of the 19th century, Bram Stoker's Dracula.

0:48:52 > 0:48:54One drop of your blood and you're bound to me.

0:48:59 > 0:49:03Now, in the book, Stoker describes Dracula drinking blood

0:49:03 > 0:49:07and becoming transformed from a little old man with white hair,

0:49:07 > 0:49:10into a dark-haired super athlete.

0:49:12 > 0:49:16Oddly enough, these dark fantasies of youthful transformation

0:49:16 > 0:49:20are actually based on a glimmer of scientific truth.

0:49:21 > 0:49:23In a climate-controlled vault,

0:49:23 > 0:49:26deep beneath the streets of London's Piccadilly, lies

0:49:26 > 0:49:30a 350-year-old record that holds the first clues.

0:49:32 > 0:49:33The natural philosophers of the period

0:49:33 > 0:49:38were simply interested in experimenting on everything.

0:49:39 > 0:49:45In 1667, the fellows of the Royal Society oversaw a gruesome first.

0:49:45 > 0:49:49Transfusing blood directly from an animal to a human.

0:49:50 > 0:49:54They wanted to test whether blood could change character,

0:49:54 > 0:49:58so they chose someone with a tempestuous nature.

0:49:58 > 0:50:01A volunteer, Arthur Coga,

0:50:01 > 0:50:06was transfused with blood from a sheep, from a lamb,

0:50:06 > 0:50:10and it was thought that perhaps the hot-headed Coga, his moods

0:50:10 > 0:50:16might be slightly tempered by the blood of this lowly, quiet animal.

0:50:16 > 0:50:19The experiment didn't kill Coga, so from that point of view,

0:50:19 > 0:50:21it's a success.

0:50:21 > 0:50:24Inspired by this success, Robert Boyle,

0:50:24 > 0:50:28the head of the Royal Society, proposed a string of further

0:50:28 > 0:50:32experiments, to find out what else blood could do to transform.

0:50:33 > 0:50:37So, here we have, "whether the colour of the hair or

0:50:37 > 0:50:41"the feathers of the recipient be changed." So could you alter

0:50:41 > 0:50:46the physical appearance of an animal by transfusing blood?

0:50:46 > 0:50:49"What will be the operation of stocking an old

0:50:49 > 0:50:53"and feeble dog with the blood of a young one, or vice versa?"

0:50:53 > 0:50:56So, will it affect ageing in a dog?

0:50:56 > 0:51:00These were fascinating questions, to these gentleman, based

0:51:00 > 0:51:04on the fact that no-one had ever practised blood transfusion before.

0:51:07 > 0:51:11In the original lamb-to-man experiment,

0:51:11 > 0:51:15surprisingly enough, the man had actually survived.

0:51:15 > 0:51:19Unfortunately, this single success was followed by years of failure.

0:51:19 > 0:51:23Subsequent attempts at blood transfusions killed

0:51:23 > 0:51:27so many people the practice was banned for nearly 200 years.

0:51:29 > 0:51:32It wasn't a safe treatment until the early 20th-century discovery

0:51:32 > 0:51:36that we each belong to one of four major blood groups.

0:51:36 > 0:51:39A transfusion of the wrong type can be fatal.

0:51:40 > 0:51:43Blood transfusions are now almost routine,

0:51:43 > 0:51:45saving millions of lives every year.

0:51:45 > 0:51:48But as we've learnt more about blood it has also lost

0:51:48 > 0:51:50much of its mystery.

0:51:50 > 0:51:53We no longer think of it as this wonderful substance

0:51:53 > 0:51:57full of vital spirits, but as a commodity, like any other.

0:52:01 > 0:52:04In the UK alone, nearly a million litres of blood a year

0:52:04 > 0:52:06pass from donors to patients.

0:52:07 > 0:52:11We now know that however much blood you transfuse,

0:52:11 > 0:52:13it won't alter your personality.

0:52:17 > 0:52:20But were the ancients entirely wrong?

0:52:24 > 0:52:28Recent discoveries have resurrected some very old ideas

0:52:28 > 0:52:30about blood's transformative power.

0:52:33 > 0:52:35The story begins with two mice.

0:52:36 > 0:52:39Now, this one is about a year old, which makes him

0:52:39 > 0:52:42middle-aged in mouse years, whereas this rather more vigorous one

0:52:42 > 0:52:46over here is about three months, something of a teenager.

0:52:46 > 0:52:49Now, in a series of rather gruesome experiments done in the 1970s,

0:52:49 > 0:52:55what they did, is they united the two rodents surgically.

0:52:56 > 0:53:02So that the blood from the young mouse ran through the old mouse.

0:53:02 > 0:53:05And when they did that they noticed, much to their surprise,

0:53:05 > 0:53:08that the older mouse became much more vigorous.

0:53:08 > 0:53:12Nothing much became of this research, and it was discontinued.

0:53:20 > 0:53:22Until recently that is.

0:53:24 > 0:53:27In the last decade, interest has been reignited.

0:53:29 > 0:53:33'I've come to Geneva to meet a pioneer in this new field

0:53:33 > 0:53:36'of rejuvenation research.'

0:53:36 > 0:53:38Now, the idea has been around for a long time,

0:53:38 > 0:53:41why has there suddenly been this recent interest?

0:53:41 > 0:53:43It was really the idea of stem cells,

0:53:43 > 0:53:45that was what first brought this idea

0:53:45 > 0:53:47of tracking things through the blood stream,

0:53:47 > 0:53:49this idea of sort of, can things

0:53:49 > 0:53:53transfer from one to the other, and that ignited this whole idea.

0:53:53 > 0:53:57But we didn't know stem cells existed, until pretty recently.

0:53:57 > 0:53:58Stem cells are unique

0:53:58 > 0:54:01because they can become many different types of cell.

0:54:02 > 0:54:06This gives them the power to repair and maintain our bodies.

0:54:06 > 0:54:09When we are young our stem cells are very active.

0:54:09 > 0:54:12But as we age they gradually switch off.

0:54:15 > 0:54:19Like human memory, the memory of a mouse gets worse with age.

0:54:21 > 0:54:22This is an old mouse.

0:54:24 > 0:54:26Only one of these holes leads to its nest.

0:54:28 > 0:54:32After 50 seconds of searching, it still hasn't found the right one.

0:54:33 > 0:54:37But watch what happens when we introduce a mouse of the same age,

0:54:37 > 0:54:39that has been infused with young blood.

0:54:41 > 0:54:44Amazingly, the treated mouse

0:54:44 > 0:54:47finds its nest in just 24 seconds.

0:54:51 > 0:54:54'When they looked at the brains of old mice treated with young blood,

0:54:54 > 0:54:58'Saul and his colleagues saw even more remarkable changes.'

0:54:59 > 0:55:02This is what our neurons look like when they're getting older...

0:55:02 > 0:55:05'This object, which looks a bit like a shrivelled peanut,

0:55:05 > 0:55:08'is an elderly neuron in an old brain.

0:55:11 > 0:55:14'It has lost many of its connections to other cells.

0:55:16 > 0:55:20'On the right, is a neuron from an old brain that has been given

0:55:20 > 0:55:21'young blood.

0:55:21 > 0:55:23'It looks completely different.'

0:55:23 > 0:55:25When you give young blood you'll see that all of a sudden

0:55:25 > 0:55:28the shape of the cell body becomes much more like a pyramid,

0:55:28 > 0:55:31and this is where all the neurons are talking to this neuron

0:55:31 > 0:55:33that's who communication occurs, learning and memory.

0:55:33 > 0:55:35So something about young blood can actually change

0:55:35 > 0:55:38the shape of the neuron itself.

0:55:38 > 0:55:40And that is very similar to what a young neuron would look like.

0:55:40 > 0:55:42Exactly, almost identical.

0:55:42 > 0:55:46Something in the young blood seems to be triggering stem cells

0:55:46 > 0:55:50into action, turning back the biological clock.

0:55:50 > 0:55:54It's a finding that's truly staggering in its implications.

0:55:56 > 0:55:58Have they done any studies in humans yet?

0:55:58 > 0:56:01As of right now, no, but they are starting to have at least

0:56:01 > 0:56:03some proof of principle clinical trials,

0:56:03 > 0:56:06especially with people that have early signs of Alzheimer's.

0:56:06 > 0:56:10So I'm lining up my sons at the moment, to donate blood.

0:56:11 > 0:56:12Can you imagine the time

0:56:12 > 0:56:16when people will start to sort of buy blood off young people

0:56:16 > 0:56:19in order to try and, you know, reverse their memories or things

0:56:19 > 0:56:22like that, or do you think it'll be something in the blood or...

0:56:22 > 0:56:24I hope they don't do that.

0:56:24 > 0:56:28It feels like a logical extension of, you know, capitalism, doesn't it?

0:56:28 > 0:56:32My hope is that, is that we can identify maybe

0:56:32 > 0:56:35the minimum amount of youthful factors

0:56:35 > 0:56:38and the minimum amount of ageing factors that we have to lower,

0:56:38 > 0:56:41and I think that'll be a much better way, a much more controlled way.

0:56:41 > 0:56:45It's quite strange, isn't it, you have this mythology around blood

0:56:45 > 0:56:48and then suddenly it turns out there is something behind it?

0:56:48 > 0:56:52All through time there's been something attributed to blood,

0:56:52 > 0:56:55and now, we're just looking at it from a different perspective,

0:56:55 > 0:56:57from the perspective of science.

0:56:57 > 0:57:00And we're actually finding out that there is something really

0:57:00 > 0:57:01unique about blood.

0:57:03 > 0:57:05If Saul and his colleagues are right,

0:57:05 > 0:57:09then ancient myths about blood had at their heart the truth.

0:57:09 > 0:57:12Perhaps there really is something in blood,

0:57:12 > 0:57:15that has the ability to turn back time.

0:57:19 > 0:57:24Blood is a hidden wonder of our body, an amazing, complex liquid

0:57:24 > 0:57:27working to keep us healthy every second of our lives.

0:57:29 > 0:57:33In recent weeks, I've certainly seen more of my own blood than

0:57:33 > 0:57:35ever before.

0:57:35 > 0:57:38I've probed its secrets and pushed its limits.

0:57:38 > 0:57:42I've seen it adapt with every breath I take, ever meal I eat,

0:57:42 > 0:57:45every time I face danger.

0:57:47 > 0:57:51For me, the real power of blood is its ability to transform.

0:57:52 > 0:57:57And this points towards fascinating developments in the future.

0:57:58 > 0:58:01During the course of making this programme I've discovered

0:58:01 > 0:58:06just why blood is feared, revered and mythologized.

0:58:06 > 0:58:10I've also seen how it can be used, abused and studied,

0:58:10 > 0:58:13and I think we'd all agree with the poet Goethe,

0:58:13 > 0:58:17who said that "blood really is a very special juice".