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The elixir of youth,

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a potion that can hold back
the hands of time,

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once seemed impossible.

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Over the years, many have claimed to
have found such a potion.

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None have.

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'Til now.

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At the start of the 21st Century,

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we are at last learning the secrets of
how to build a longer lasting human.

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The search for the elixir of youth
starts inside the cell.

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Here, rogue elements cause most of
the damage that we call ageing.

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If we can reduce this damage,

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we might slow the seemingly inevitable
decline to old age.

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Scientists have recently shown

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that it's possible to double
the lifespan of an animal.

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Here was a perfectly normal animal
which just simply lived twice

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as long as its genetic counterparts.

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And experts in ageing now believe that
human lifespan can also be doubled,

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to well over a 150 years.

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I think 150 years is really
a conservative estimate.

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I wouldn't be surprised
if it's not substantially longer.

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Over the last century,

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life expectancy has almost doubled.

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We can expect to live a good 30 years
longer than our great grandparents.

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To double our current lifespan,

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molecular biologists are
manipulating our cells.

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For the first time, they have proof that
delaying ageing is possible.

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But not everyone thinks
it should be done.

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If you talk to any molecular geneticist
in the world today,

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they will have to admit to you
that this could happen.

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They may hate it, with all of
their heart they may hate it,

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but they have to admit that

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the technology exists
for this to happen.

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Drugs that have doubled the lifespan of
animals may soon be tested on humans.

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But are we ready for the changes a true
elixir of youth would bring?

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Long ago, some animals learnt the trick
of living a very long time.

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The hydra, for example.

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This microscopic fresh water creature
looks unremarkable,

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but the hydra possesses
one impressive ability,

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time passes, but its youth and
vigour never decline.

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Strangest of all, when researchers break
hydras down to their very cells,

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something extraordinary occurs.

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In a matter of hours, out of the mass
of cells rise fully grown hydras.

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Hydras, however, are very simple.

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We are not.

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The human body is made up

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from 100 million million million
different cells.

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Some are manufactured continuously.

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A 170 billion red cells form daily
to carry oxygen.

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10 billion white cells form to
fight disease.

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Others, like the cells of
the nose and ear,

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renew themselves so vigorously,

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they just keep on growing
all life long.

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But, eventually, something goes wrong.

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Cur cells start to feign,
our skin wrinkles,

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our hair greys, and eye-sight fades.

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Is there anything we can do to
turn back the clock?

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Leading choreographer, Gillian Lynne,

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doing an impressive job
at staying young.

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She keeps age at bay through
sheer hard work.

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She exercises
for three hours everyday.

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It's hard to believe she's 75 years old,

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and can still go toe to toe
with the 20 year olds.

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The difficulty about trying to fight
the ageing process is that

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we're told that from the age of 25
the body starts to deteriorate.

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I can't say that it's easy, it isn't,
and it's mostly painful.

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If you want to remain at all young,
there are no shortcuts.

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Well, as you see,

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I've done quite well in keeping age
at bay by exercising.

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But there's one bit of me I'm afraid
I can't control at all,

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look at this, the famous skin test.

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Slow like a tortoise.

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And the effects of ageing are not
just superficial.

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These days, Gillian can only dance
thanks to artificial hip joints.

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Regular exercise will help you live
a little longer,

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but keeping forever young requires
something more.

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One man who claims he does possess that

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extra something is Doctor Ron Livesy.

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He runs a private anti-ageing clinic
in New York.

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He believes his treatment programme
will slow down,

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even reverse the ageing process.

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He's in his mid-50s and he's
on it himself.

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I've noticed many benefits
over the past five years.

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I've regained my lean body mass and

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lost approximately
60Ibs of abdominal fat.

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My immune system is clearly
working much better,

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because I no longer get frequent colds

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and no longer require sick days
from work.

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My bad cholesterol is now normal,

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my good cholesterol has gone from being
low to a quite healthy range.

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Diane Gilman is one of
Doctor Livesy's clients.

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At 56, she has also decided not to
give in to age.

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I was always the kind of person that

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believed you could fight mother nature.

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If you ate right,
if you exercised right,

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if you got enough sleep,

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and at about 50 years old
I just hit a brick wall.

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Mother nature said, aha, those aren't
the plans I have for you.

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I couldn't fight all of the things
that were happening to me,

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many of which I didn't even understand
were about ageing.

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Horrible back pains, terrible pains
and cramps in my legs.

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Diane's main weapon
in the war against ageing

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is called human growth hormone.

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Whilst we're going through childhood
and adolescence,

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our bodies are churning out
large amounts of growth hormone.

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It helps build muscle
and repair tissues.

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At about the age of 25, levels peak,

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then start to drop off.

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By the time we reach old age,

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our bodies are producing very little.

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Diane is injecting herself
with just enough growth hormone

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to push her levels back to those
she had when she was 25.

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This requires two shots a day,
at a cost of over $1,000 a month.

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I will never forget the first day that

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I injected myself
with human growth hormone.

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I felt like a watch.

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If you have a watch
where you can see all the cogs

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and mechanisms working on the back,

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it was like everything was working and
going in one direction,

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which everything came to a halt

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and then started to go
in another direction.

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It really has turned back
the hands of time.

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Diane's daily injections have helped
transform one symptom of ageing,

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removing those extra pounds
from her waistline.

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The short term slimming effect of
growth hormone is well known to doctors.

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This patient has had a brain tumour.

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It stopped him producing growth hormone.

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He is being given doses of artificial
growth hormone,

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and he's experiencing
the same loss of fat as Diane.

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He's in the hands of hormone expert,
Professor Stephen Shalet.

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It does have a profound effect,

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the amount of fat on their body is
dramatically reduced,

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and the amount of muscle is
significantly increased.

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This scan is of the cross section of
a middle aged man.

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It shows light areas of fat,

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not only round the belly,
but also inside.

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Thick layers cover the major organs.

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After six months of growth hormone,
much of the fat has gone.

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Could it be that growth hormone is
the wonder drug,

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the key to building
a long living human?

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I think it's unfortunate
that one of the tags

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that growth hormone was given was
the elixir of youth.

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There is no objective evidence

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that growth hormone
treatment prolongs life.

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And there is a risk in using growth
hormone when you're middle aged.

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Cancer.

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Growth hormone could encourage
cancer cells to spread more rapidly.

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The risks of an individual
developing cancer,

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far outweigh any potential benefits,

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so I think it's extremely unwise,

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and a road that we should not go down.

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I weighed the risks and the conclusion
I came to was,

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you know what, I got nothing to lose here.

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I've got everything to gain.

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And so far, so good.

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I'm up for the challenge.

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I would like to see what
the next 100 years brings for me.

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While it is extremely unlikely
that Diane will live to over a 150,

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there are some animals that can.

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Animals like Harriet.

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She is over 170 years old,

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which makes her one of the oldest
creatures on the planet.

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She was born before Victoria was Queen.

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She was already five years old

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when Charles Darwin paid her a visit

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on his historic voyage
to the Galapagos Islands.

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Harriet may not be immortal,

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but she's living proof that some animals

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are much more successful than we are
at resisting ageing.

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The question is, how?

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Clues lie in a shared ancestor,

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one who lived a long, long time ago.

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Four billion years ago,
when life started on this planet,

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the world looked very different.

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Volcanoes were active, belching in
to the atmosphere,

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a mixture of carbon dioxide
and sulphur.

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These gases would have coloured
the sky red.

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Blue green algae dominated the planet.

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They used the energy from the sun

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and combined it with the gases
in the atmosphere to make food.

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But, as they spread over the planet,

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these algae produced this new gas:

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Oxygen.

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Levels in the atmosphere slowly rose
from almost nothing to over 20%,

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and turned the sky blue.

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But for early life, oxygen was
a major hazard,

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because oxygen is a highly explosive,
reactive gas.

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One man who knows just
how dangerous it can be,

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is pyrotechnics specialist,
Malcolm Armstrong.

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Oxygen is one of the most reactive gases
on planet earth.

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Chemical explosions require
two components, fuel and oxygen.

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Here, Malcolm fills a tube with
a little fuel and a little oxygen.

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The effect is underwhelming.

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Now, keep the same amount of fuel
and increase the oxygen.

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I've put 300 times the amount of oxygen
in here.

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And it becomes a very different story.

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Oxygen is dangerous.

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Two and a half billion years ago,

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oxygen would have killed
most of the life forms

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it came in contact with.

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But one microbe found a way of

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harnessing the explosive
power of this gas.

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It's called a mitochondrion.

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Each mitochondrion became
a miniature power station.

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What followed next was one of
the most important steps

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in the history of life on this planet,

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and is perhaps the most vital clue of
all as to why we age.

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Two of the many single cells
joined forces.

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The tiny power plant,
one of the mitochondria,

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was absorbed in
to another primitive cell.

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Life on earth changed forever.

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Today, mitochondria live inside
the cells of every living creature.

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An expert in molecular biology,

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John Burn, is fascinated

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by our relationship
with this early organism.

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Most people had never heard
the word mitochondria,

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and yet the cells in my brain that are
thinking of these words,

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and the cells in my tongue that are
helping to form them,

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get their energy from mitochondria.

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Every living creature on this planet has
mitochondria within their cells.

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They are the power plants
that fuel all life, including us.

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They're like millions of tiny batteries,

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and when it was first suggested

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that mitochondria might once have been
free living bacteria,

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it seemed almost impossible to believe.

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These ancient bacteria
really are everywhere.

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For example, in the tails of sperm.

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A new laser scanning microscope
allows us to see,

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for the first time, how individual
sperm are powered by mitochondria.

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They are the glowing section
in the tail

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that propel the sperm in their frantic
journey to fertilise the egg.

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And it's the same story with eggs.

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They are so densely packed
with mitochondria,

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that under the laser they glow,
like the sun.

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Mitochondria are the power sources

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that will drive the growth spurt
to build a new human.

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Cur every movement is powered by them.

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And our every breath brings them
the oxygen they need.

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But there's a heavy cost.

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With every breath we age.

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Life giving oxygen is slowly killing us.

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Because oxygen isn't just explosive,
it's corrosive.

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When oxygen touches pure iron it starts

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a chemical reaction
that turns it to rust.

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This nail turned rusty by exposure to
oxygen has been eaten away.

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And if oxygen can do this to metal...

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00:21:03,194 --> 00:21:06,061
just imagine what it can do
to your body.

247
00:21:17,708 --> 00:21:21,872
It seems almost unbelievable that
we're sitting here in 20% oxygen,

248
00:21:22,013 --> 00:21:23,878
breathing it, depending on it,

249
00:21:24,015 --> 00:21:28,247
and yet that same oxygen inside our body
is actually doing damage,

250
00:21:28,386 --> 00:21:30,650
it's like rusting us from the inside.

251
00:21:30,788 --> 00:21:31,982
If you think about it, the atmosphere

252
00:21:32,123 --> 00:21:33,750
should probably have a health warning.

253
00:21:36,260 --> 00:21:40,060
The trouble is that it's not just
oxygen that's corrosive.

254
00:21:40,531 --> 00:21:41,998
So are its by-products.

255
00:21:43,467 --> 00:21:45,059
Inside the mitochondria,

256
00:21:45,202 --> 00:21:49,571
most of the oxygen we breath is
transformed in to life giving energy.

257
00:21:50,408 --> 00:21:51,739
But not all.

258
00:21:52,743 --> 00:21:57,077
Some oxygen degrades in to particles
called free radicals.

259
00:22:02,320 --> 00:22:05,346
The trade-off, more power
but more damage,

260
00:22:05,489 --> 00:22:08,390
intrigues biologists
like Gordon Lithgow.

261
00:22:14,598 --> 00:22:16,725
Mitochondria is really like
an alien invader.

262
00:22:16,867 --> 00:22:18,698
It's a bit of a pact with the devil.

263
00:22:18,836 --> 00:22:21,498
We get from the mitochondria lots of
cheap free energy,

264
00:22:21,639 --> 00:22:24,733
but also it's possible we get ageing.

265
00:22:28,746 --> 00:22:30,179
The mitochondria are a bit like

266
00:22:30,314 --> 00:22:32,509
a nuclear power station
in your back garden,

267
00:22:32,650 --> 00:22:34,242
lots of cheap, free energy,

268
00:22:34,385 --> 00:22:38,014
but highly toxic by-products
that have to be managed.

269
00:22:38,789 --> 00:22:44,159
One released, free radicals can damage
any part of any cell in the body.

270
00:22:44,762 --> 00:22:49,722
Worst of all, they strike at the genes
at the heart of every cell.

271
00:23:15,893 --> 00:23:17,827
So what's the proof that this battering

272
00:23:17,962 --> 00:23:21,523
inside leads to the decay
we know as ageing?

273
00:23:23,033 --> 00:23:24,728
Forensic pathologist, Dick Shepherd,

274
00:23:24,869 --> 00:23:26,359
sees the sign of oxygen and

275
00:23:26,504 --> 00:23:29,837
free radical damage
almost every working day.

276
00:23:31,308 --> 00:23:34,766
We see damage caused by oxygen
in almost everybody that we examine.

277
00:23:34,912 --> 00:23:36,777
It's present at a cellular level,

278
00:23:36,914 --> 00:23:38,176
but we see it with the naked eye

279
00:23:38,315 --> 00:23:40,340
in the brain and
the heart and the lungs.

280
00:23:51,262 --> 00:23:52,354
The lungs are the first point

281
00:23:52,496 --> 00:23:56,091
at which the atmospheric oxygen reaches
in to the body,

282
00:23:57,635 --> 00:23:59,262
passes through tiny little spaces

283
00:23:59,403 --> 00:24:03,669
that are lined by single layers of cells
in to the blood stream.

284
00:24:05,843 --> 00:24:06,832
But, of course, these cells,

285
00:24:06,977 --> 00:24:10,674
although they are there to
transport the oxygen,

286
00:24:10,815 --> 00:24:12,806
are also particularly vulnerable.

287
00:24:15,920 --> 00:24:19,185
And this is normal lung,
smooth surface,

288
00:24:19,323 --> 00:24:21,291
big blood vessel running down
the middle of it.

289
00:24:21,425 --> 00:24:24,394
There are no holes,
there are no abnormalities.

290
00:24:27,398 --> 00:24:32,199
A lifetime of exposure to pollutants
like smoking, will change that.

291
00:24:33,170 --> 00:24:35,331
Tobacco smoke dramatically increases

292
00:24:35,473 --> 00:24:37,703
the production of free radicals
in the body,

293
00:24:37,842 --> 00:24:40,834
leading to cancer and
other lung disorders.

294
00:24:46,417 --> 00:24:48,681
In this lung, the damage is obvious.

295
00:24:53,123 --> 00:24:57,184
The damage done by free radicals can
also be seen in other organs.

296
00:24:57,328 --> 00:24:59,489
Cardiovascular disease,
that's disease of the heart

297
00:24:59,630 --> 00:25:02,497
and the blood vessels is the number
one killer throughout the world.

298
00:25:03,634 --> 00:25:08,469
As it circulates, blood carries oxygen
and free radicals around the body.

299
00:25:09,373 --> 00:25:12,774
Over time,
they can damage artery walls.

300
00:25:13,444 --> 00:25:14,809
Combined with cholesterol,

301
00:25:14,945 --> 00:25:18,210
this leads to furring up of
important blood vessels.

302
00:25:18,749 --> 00:25:20,774
This is the inside of the aorta,

303
00:25:20,918 --> 00:25:22,715
the biggest blood vessel of the body.

304
00:25:23,454 --> 00:25:30,485
A thin, smooth tube, a perfect vessel
for the transport of blood.

305
00:25:31,595 --> 00:25:36,692
And this is what an aorta that's got
severe fatty deposits looks like.

306
00:25:37,668 --> 00:25:38,760
The fat has been affected

307
00:25:38,903 --> 00:25:42,236
by the oxidation and
formed this rancid butter

308
00:25:42,373 --> 00:25:44,933
which has caused weakening of the wall.

309
00:25:45,943 --> 00:25:48,241
The fatty deposition starts in our 20s,

310
00:25:48,379 --> 00:25:51,314
but it may be 40 years or
so until the effects

311
00:25:51,448 --> 00:25:53,541
become obvious to the individual.

312
00:25:58,756 --> 00:26:01,190
The brain is about 2% of the weight
of the human body,

313
00:26:01,325 --> 00:26:03,691
but consumes about 20% of the oxygen.

314
00:26:04,228 --> 00:26:07,322
And we're all worried about the effects
of dementia as we get older,

315
00:26:07,464 --> 00:26:09,261
and we do know that the brain cells are

316
00:26:09,400 --> 00:26:12,528
particularly susceptible
to the toxic effects of oxygen.

317
00:26:15,573 --> 00:26:19,065
A young brain glows
with huge numbers of mitochondria.

318
00:26:20,010 --> 00:26:21,500
But as time goes by,

319
00:26:21,645 --> 00:26:22,942
the free radicals produced

320
00:26:23,080 --> 00:26:25,344
by the enormous energy demands
of the brain,

321
00:26:25,482 --> 00:26:27,643
begin to kill the mitochondria.

322
00:26:30,054 --> 00:26:32,488
One by one, the batteries fail.

323
00:26:34,191 --> 00:26:35,920
And so does our brain.

324
00:26:37,161 --> 00:26:38,890
Memory becomes impaired,

325
00:26:39,363 --> 00:26:42,059
and thinking becomes confused.

326
00:26:43,167 --> 00:26:46,261
When we dissect brains we can sometimes
see those changes.

327
00:26:49,773 --> 00:26:53,766
Old brains show extensive signs of
free radical damage.

328
00:26:54,511 --> 00:26:56,502
In some brains, like this one,

329
00:26:56,647 --> 00:27:00,606
the damage is greatest amongst the cells
that control movement.

330
00:27:11,862 --> 00:27:16,128
Normal brains have a healthy dark line
of these specialist cells,

331
00:27:16,700 --> 00:27:20,067
but in the brain on the right,
the dark cells are no longer visible.

332
00:27:20,738 --> 00:27:24,674
They have been destroyed
by the products of oxygen.

333
00:27:28,245 --> 00:27:31,373
Given that we know
the effects of oxygen,

334
00:27:31,582 --> 00:27:34,483
it's not a surprise that we age
or we grow old.

335
00:27:34,985 --> 00:27:36,543
What is surprising though is that

336
00:27:36,687 --> 00:27:40,088
we actually live so long and remain
so healthy.

337
00:27:44,695 --> 00:27:47,129
The link between oxygen and ageing helps

338
00:27:47,264 --> 00:27:51,564
explain a curious observation made
over a 100 years ago.

339
00:27:52,703 --> 00:27:54,466
The observation that most animals

340
00:27:54,605 --> 00:27:59,736
have a fixed number of heart beats
in their lifetime, around a billion.

341
00:28:03,213 --> 00:28:05,545
A shrew lives life in the fast lane.

342
00:28:06,316 --> 00:28:08,876
Its heart skips along
at 500 beats a minute,

343
00:28:09,019 --> 00:28:12,546
using up all its heartbeats
in less than four years.

344
00:28:21,665 --> 00:28:26,796
By contrast, an elephant's heart pumps
a leisurely 30 times a minute.

345
00:28:27,337 --> 00:28:29,601
It can live up to 80 years.

346
00:28:32,109 --> 00:28:33,906
And a tortoise, like Harriet,

347
00:28:34,044 --> 00:28:38,777
with a very low resting heart rate,
just goes on and on.

348
00:28:40,517 --> 00:28:43,680
The more you rush around,
the more oxygen you need,

349
00:28:43,921 --> 00:28:46,014
and the more free radicals you product.

350
00:28:56,200 --> 00:28:59,294
And more free radicals
means more damage.

351
00:29:08,679 --> 00:29:11,739
If free radicals are the main reason
why we age,

352
00:29:11,882 --> 00:29:13,679
then perhaps we should be
looking at ways

353
00:29:13,817 --> 00:29:15,910
to reduce the amount we produce.

354
00:29:23,026 --> 00:29:25,017
Michael Young is in training.

355
00:29:28,966 --> 00:29:30,763
He's hoping that his training
will allow him

356
00:29:30,901 --> 00:29:34,064
to live an exceptionally long
and healthy life.

357
00:29:34,705 --> 00:29:36,400
Michael is nowhere near as fit or

358
00:29:36,540 --> 00:29:39,134
as strong as the men he's swimming with.

359
00:29:43,580 --> 00:29:47,209
But he's convinced that despite
outward appearances,

360
00:29:48,252 --> 00:29:51,153
it is he who will win the race of life.

361
00:29:57,795 --> 00:30:03,233
Michael is 42 years old, and determined
to live at least as long again.

362
00:30:04,701 --> 00:30:09,263
His life plan is not based on exercise,
but diet.

363
00:30:09,640 --> 00:30:12,973
Essentially, it's an attempt to grow
older more slowly, really,

364
00:30:13,110 --> 00:30:16,273
and to minimise the dangers from all
these degenerative diseases

365
00:30:16,413 --> 00:30:17,607
that are going to happen by the time

366
00:30:17,748 --> 00:30:20,842
most people are 60 or 70,
they're going to start.

367
00:30:20,984 --> 00:30:23,782
And I want them to start a little bit
later in my life,

368
00:30:23,921 --> 00:30:25,786
and that's what I'm on this diet for.

369
00:30:30,194 --> 00:30:33,755
Michael has read extensively
on the science of ageing,

370
00:30:34,097 --> 00:30:38,056
and for the past three years he's been
putting theory in to practice.

371
00:30:38,702 --> 00:30:42,035
He has begun a radical vegetarian
based diet.

372
00:30:46,610 --> 00:30:48,373
That's because fruit and vegetables

373
00:30:48,512 --> 00:30:52,573
are the best source of vitamins,
like A, C and E.

374
00:30:53,150 --> 00:30:55,880
These are so-called antioxidants.

375
00:30:56,019 --> 00:30:58,419
They help soak up free radicals.

376
00:30:58,555 --> 00:31:01,922
But fruit and veg alone will not
greatly extend life.

377
00:31:02,426 --> 00:31:04,326
So Michael also plans to reduce

378
00:31:04,461 --> 00:31:07,726
the amount of free radicals
his body produces.

379
00:31:07,998 --> 00:31:12,492
He's trying to do this by eating less,
far, far less.

380
00:31:12,870 --> 00:31:16,067
I find Fridays is a good day
for actually eating not very much,

381
00:31:16,206 --> 00:31:18,504
because that's the day when I go to
my war games club,

382
00:31:18,642 --> 00:31:20,667
and the excitement of
the war games club,

383
00:31:20,811 --> 00:31:23,644
and playing with the model soldiers
takes my mind off the fact

384
00:31:23,780 --> 00:31:25,179
that I'm actually quite hungry.

385
00:31:26,083 --> 00:31:29,610
And so often I'll manage on just perhaps
an apple on Fridays.

386
00:31:37,995 --> 00:31:41,522
Michael is, by profession,
a military strategist,

387
00:31:41,798 --> 00:31:44,926
and when it comes to ageing,
he has studied the odds.

388
00:31:49,806 --> 00:31:53,242
He eats less than 1500 calories a day.

389
00:31:53,911 --> 00:31:56,379
And this diet isn't
a short term tactic,

390
00:31:56,813 --> 00:31:58,781
it's a lifelong campaign.

391
00:32:04,588 --> 00:32:07,614
Michael is right that a diet high
in fruit and veg

392
00:32:07,758 --> 00:32:11,489
and low in fat will help him
avoid mid life diseases.

393
00:32:12,095 --> 00:32:15,861
But, will eating less help him
live longer?

394
00:32:21,772 --> 00:32:27,472
It sounds unlikely, unless you know
the dramatic tale of two mice.

395
00:32:33,417 --> 00:32:36,409
For mice, everything is in fast forward.

396
00:32:38,822 --> 00:32:44,818
From tot to teens in a few months,
then old age and death at two.

397
00:32:48,398 --> 00:32:50,161
But this isn't inevitable.

398
00:32:50,767 --> 00:32:54,897
In what is now a classic experiment,
researchers took two young mice.

399
00:32:57,607 --> 00:33:00,405
One mouse was allowed to eat
as much as she liked.

400
00:33:03,847 --> 00:33:07,044
She lived
a typical couch potato existence,

401
00:33:07,284 --> 00:33:09,809
and died soon after reaching two.

402
00:33:14,358 --> 00:33:16,849
The other mouse led a spartan existence.

403
00:33:16,994 --> 00:33:19,155
She got half the number of calories.

404
00:33:20,330 --> 00:33:22,594
She lived on, bright and active,

405
00:33:22,733 --> 00:33:25,099
dying at the grand old age of three.

406
00:33:28,538 --> 00:33:32,201
In human years, that over 120.

407
00:33:34,711 --> 00:33:37,680
It must have been one of the really
exciting moments in science,

408
00:33:37,814 --> 00:33:39,645
back in the 30s,
when they suddenly realised

409
00:33:39,783 --> 00:33:43,219
that simply by changing how much food
a mammal ate,

410
00:33:43,353 --> 00:33:44,843
they could change how long it lived.

411
00:33:44,988 --> 00:33:46,979
I mean, it opened up all sorts
of po