[female narrator] Every life...
has a lifespan.
The C. elegans worm gets on average 14 days on Earth.
European lobsters get up to 50 years.
The Bristlecone pine tree, as much as 5,000.
And humans?
We have a maximum lifespan of around 120.
As best we can tell, some people throughout history made it past 100.
One tombstone of an ancient Roman soldier
states simply, "Vixit annis C." "He lived 100 years."
But for most of human history, you were pretty lucky to make it past five.
Just 200 years ago,
no country on Earth had a life expectancy higher than 40.
But then, that number started ticking up.
City's engineered ways to give people clean water.
We discovered that germs caused disease.
[man] The germs have to leave the body of a sick person
and enter the body of one who is well.
[narrator] And started regularly washing our hands with soap
Nutrition improved, and we invented new ways to keep food safe.
We discovered antibiotics and we developed vaccines,
knocking out some of the worst killers mankind has ever known.
Since 1800, the average life expectancy worldwide has more than doubled
to around 72 years.
And the biggest reason is that you're now far less likely
to die of an infectious disease before you reach old age.
But for people who reach old age,
their life expectancy hasn't increased much at all.
In England and Wales in 1840,
a 70-year old could expect to live to 79.
Today, it's 86.
A hundred and eighty years of scientific advancement
for just a seven-year bump.
If the human lifespan is 120 years,
why, even in developed countries,
do most of us only make it two-thirds of the way there?
What is it about old age that kills us?
And is it treatable?
Today's drugs truly work medical miracles, for young and older lives.
[man] It was only 1930.
You get a disease, you die.
And then suddenly, you take a pill and you live.
[woman] Aging is only now coming into its own.
I really think we could be on the eve of a whole new era.
[man] The finiteness of life.
It forces me to appreciate every sunrise.
[narrator] So, what is aging?
Some of its symptoms are hearing loss,
poor eyesight,
weakened muscles,
our heart rate slows, our blood pressure rises,
and our brains become less nimble and more inclined to forget.
Our ability to stay focused on a problem
declines with aging.
There's a series of problems, all of which accumulate
such that the quality of life diminishes.
The amount that we can actually live actively in the world goes down.
[narrator] And as we age,
our risk of dying from a chronic disease skyrockets.
Aging is the major risk factor for death
for any one of those diseases we're afraid from.
From cancer, from cardiovascular disease,
from Alzheimer, from diabetes.
Now, you might stop me and say, "Just a minute!
For cardiovascular disease, isn't it cholesterol?"
Well, cholesterol is a three-fold risk.
But aging is a 5,000-fold risk.
[narrator] In the US, the majority of deaths
are now caused by a chronic disease associated with old age.
The costs are extraordinary.
86% of healthcare spending in the US goes towards treating chronic diseases.
Finding cures for these diseases has been a fixation
of governments, and scientists, and societies.
With a new moonshot, America can cure cancer.
An incoming coalition government will commit an additional 200 million dollars
to dementia research.
Heart disease is the number one killer of women.
[narrator] But we haven't found one yet.
So some researchers have proposed a different strategy,
focusing on what they see as the underlying cause.
Aging.
Scientists have estimated that if we cured all cancers,
that would only extend lifespan by about four years on average,
because people would get sick from some other disease.
And if we're successful in finding the targets that drive aging
and we can slow aging down,
then that's going to affect the rate of disease.
If you have a leaky faucet in your house and you want to fix it,
there couple ways to do it. One is you put a bucket under the faucet.
You have to empty that bucket every week, and it's just a big hassle.
On the other hand, if you just go under the sink and you find the part of the pipe
that is leaking and you fix that,
that gets rid of your whole issue.
And so what we think about in the aging field
is how can we find the core problem
that is actually causing all these downstream pathologies and fix that
and eliminate the chances of any of them actually occurring in the first place? [narrator] Aging is the result of the biological accumulation
of damage in our cells.
This damage actually starts before we're born.
Soon after conception, our cells start duplicating
so our tissue can grow and regenerate.
As our cells copy themselves,
they make errors that cause molecular damage.
For about two decades, we are able to repair those mistakes.
But by the time we are in our 30s,
aging is accelerated.
Fighting this process isn't a new idea.
We're constantly bombarded with ads for products
promising to restore our youth.
The angi-aging industry is now worth 250 billion dollars
and growing.
[woman] It's clinically proven to give ten years back to the look of skin.
[woman 2] With Olay, you age less.
[woman 3] Visibly younger-looking skin. Youth is timeless.
[narrator] Most of the anti-aging market
is focused on the symptoms of aging you can see, like wrinkles,
and marketed mostly to women. Not the wrinkles themselves.
They haven't been scientifically tested to actually change the skin.
Forget looking younger.
Some people have tried to cheat death entirely.
In the 1960s, we came up with cryonics,
freezing a person as soon as they die
with the plan of reviving them in the future,
once science has figured out how.
I think cryonics
takes the human body a little bit too seriously.
My inclination is the doubt that simply saving the body
is going to be enough to make it possible to resurrect a person.
And in particular, a person who's at all like the person who died.
Because that's the other problem if your brain has changed a lot.
[narrator] But some people believe there's a solution for that:
preserving the brain by uploading it to a machine.
Seems to me rather unlikely that we can load up my consciousness
into a machine.
My consciousness, I think, is deeply connected
with its biological existence in my brain.
And I assume that what people care about, when they care about continuing,
is continuing as a conscious person.
[narrator] These are ideas to fight death.
But they don't fight the biological process of aging.
Science has mostly accepted that aging is a part of life.
If you look around at different species of animals,
what you notice right off the bat is very striking,
especially if you have had a dog,
is that the rate of aging of different species is different.
So, a dog...
has a lifespan that's seven times shorter than ours.
Aging could just sort of happen,
but why does it happen at such a different rate in different species?
[narrator] Then in 1961, we found a clue.
Dr. Leonard Hayflick discovered that many human cells
stopped dividing after about 50 divisions.
It seemed our cells had death programmed into them at birth.
Then, in the 1980s,
we figured out the cause.
The chromosomes in our cells
had protective caps on them, called telomeres,
and with every cell division those caps got shorter.
When the telomeres couldn't protect our chromosomes anymore,
our cells died.
The solution to that seems pretty clear.
We need to engineer our cells so our telomeres don't get too short.
But as it turns out,
cells like that already exist.
Cancer cells.
Nobody's been able to solve that puzzle yet.
But around the world,
a handful of communities seem to have figured out a secret to living long.
In this cluster of Sardinian villages, one in six hundred people make it to 100,
six times higher than the national average.
And on the Greek island of Ikaria, one in three people make it to 90,
living nearly a decade longer than mainland Greeks.
All their lifestyles have a lot in common.
Daily exercise,
a rich social life,
and a mostly vegetarian diet,
washed down with a couple glasses of red wine.
How you live clearly affects how long you live.
But some things are out of your control,
and we know that
because of this worm.
The C. elegans worm has an average lifespan of 14 days,
and both of these worms are 13 days old.
But scientists mutated a gene in the one on the left.
It isn't just acting younger, its lifespan doubled.
It was such a striking result that people didn't believe it,
when it first came out almost.
Scientists had knocked out a gene called DAF-Two that regulates insulin,
which meant the worm absorbed far fewer nutrients.
We basically tricked the worm's body into thinking it was fasting.
If you eat a meal, the tissues have little doors in them
and they'll take the food in,
but in order to do that, they need the hormone insulin.
If you have less insulin,
or if you have a receptor for insulin that doesn't work as well,
which is like the DAF-Two mutant receptor,
then the animal doesn't think it has enough food. He thinks, "Uh-oh.
I'm headed for difficult times now. I'm gonna be careful.
I'm gonna protect my cells, gonna fold my proteins better.
I'm gonna make sure my DNA doesn't get damaged."
So once the cells are in that good taken-care-of state,
I think the animal can just live longer.
[narrator] Scientist mutated the same gene in fruit flies
and their lifespan nearly doubled.
In mice, it extended their lives by 50%.
All these organisms not only lived longer,
but they were more resistant to multiple chronic diseases.
If one gene, in one pathway,
can modulate the rate of aging, we're in business.
It changed our field totally.
It took us from hope to promise.
[narrator] All the people through history who lived to 100 or 110,
or 120, maybe they had a genetic mutation.
After that breakthrough, research on lifespan extension took off.
Within the next few years, we're gonna add ten to twenty years to life.
We know that this is achievable
because there are already humans that lived to be past the age of 100.
They're called centenarians. These people aren't just lucky,
it's genetically controlled,
because their children are also more likely to live past the age of 100.
[narrator] People who live past 100 get sick much later in life
and for a shorter period of time than people with a more average lifespan.
If we can find out what these secrets are, then we can develop drugs that mimic them
for the rest of us, so we can all live longer and healthier.
Investors have started betting serious money on finding what those secrets are,
funding a flurry
of new companies focused on the science of longevity.
[woman] We test different drugs at Insilico,
in order to see how they can change the difference between young and old.
[man] The goal at Human Longevity INC., is to change the face of aging.
[man 2] Elysium is sparking new discoveries
and bringing the science of living healthier for longer to you.
[narrator] One promising lead with a lot of money behind it?
Senescent cells.
Sometimes when a cell stops dividing, it doesn't die.
It keeps sending out chemical signals.
And these zombie cells build up in our bodies as we age.
Clearing out those cells in mice
significantly improved their health and lifespan.
These startups are racing to create the first proven anti-aging treatment.
But there's a chance they might be beaten by a drug that already exists.
The field of aging has been fascinated
by the fact that there are drugs on market today
which potentially impact human aging that were approved for other diseases.
[narrator] And for a lot of people in the field
the great hope now is the anti-diabetes drug metformin.
The active ingredient in metformin comes from the plant Galega officinalis,
also known as goat's rue,
false indigo, professor-weed,
French lilac,
Spanish sainfoin,
and Italian fitch.
One major UK study showed that 78,000 diabetes patients taking metformin
lived a little bit longer than non-diabetics.
People with diabetes who take metformin compared to other drugs
have 30% less cardiovascular disease.
People with diabetes who are on metformin have 30% less cancers.
[narrator] Remember the worm and how we mutated its DAF-Two gene?
Metformin actually acts on the human version of that same gene,
regulating insulin.
And works through other molecular mechanisms we don't totally understand.
The US Federal Drug Administration approved a metformin trial
as a possible treatment for age-related diseases,
not for aging itself,
because the FDA doesn't recognize aging as something that's treatable.
But if the results come back positive,
that might change, opening the floodgates for more research.
I'm very optimistic that this is going to be accelerated,
and that the next decade is really going to be the turning point to target aging.
One of the exciting things for me is it could be the case
that none of this translates to humans, that's a possibility.
But if any of it works, it changes the paradigm completely.
This is the beginning of a new way to think about medicine.
[narrator] But we may not even want a world where everyone lives to 120.
I've never heard anyone say they want to, like, be the winner,
they want to beat the odds and live longer than anyone ever has lived.
It's typically that you want to be able to have good years for as many as you get.
One hundred and twenty? As long as you can be healthy.
No asthma,
no heart trouble, you know,
and no bad legs.
That'd be wonderful.
Then it brings up other questions, like,
do I have enough money to survive that way?
Part of aging is you might outlive your money.
Why do cells age, why do organisms age, why do organisms age and die?
That's a great puzzle to solve. It's a challenging puzzle to solve.
But that doesn't mean solving it and getting a therapy for it
is gonna be a good thing for planet Earth.
[narrator] Centenarians might be healthier than other people in old age,
but they're still old.
They're probably not going to work a job, and they'll need some care,
and that has a cost.
And these costs are hard to cut back.
Caring for the elderly in many societies is seen as a moral imperative.
If you look at countries that have very long life expectancies like Japan,
what ends up as you have a lot of old people
who are very isolated and lonely.
And you got frequent reports in Japan of people dying and no one noticing.
[narrator] And we still haven't finished the project we began two centuries ago:
getting every child to make it to old age in the first place.
Once you're past 75,
getting it to 85 or 90 should not be our goal.
What our goal should be is to get everyone to 75.
[narrator] If older people live longer,
the ratio of elderly to the young shifts,
and that changes society.
Studies have shown that when a population becomes more elderly,
countries become less entrepreneurial.
And if a population doesn't die at all, we might stop doing much of anything.
As that wonderful Star Trek episode shows,
you would run out of things that you could possibly think were worth doing
if you had infinite time.
There's nothing left to say.
Can't you see, Captain?
For us, the disease is immortality.
The fact that my life has a beginning, a middle, an end
is a really important part of what frames the questions about what I'm doing.
In fact...
living with limitations is precisely what gives life meaning.
Life's meanings derives from the challenges we face.
And taking away all challenge makes life completely uninteresting.