Thank you very much.

Well, I would like
to start with testicles.

(Laughter)

Men who sleep five hours a night

have significantly smaller testicles
than those who sleep seven hours or more.

(Laughter)

In addition, men who routinely sleep
just four to five hours a night

will have a level of testosterone

which is that of someone
10 years their senior.

So a lack of sleep
will age a man by a decade

in terms of that
critical aspect of wellness.

And we see equivalent impairments
in female reproductive health

caused by a lack of sleep.

This is the best news
that I have for you today.

(Laughter)

From this point, it may only get worse.

Not only will I tell you
about the wonderfully good things

that happen when you get sleep

but the alarmingly bad things
that happen when you don't get enough,

both for your brain and for your body.

Let me start with the brain

and the functions of learning and memory,

because what we've discovered
over the past 10 or so years

is that you need sleep after learning

to essentially hit the save button
on those new memories

so that you don't forget.

But recently we discovered

that you also need sleep before learning,

and now to actually prepare your brain,

almost like a dry sponge

ready to initially soak up
new information.

And without sleep,
the memory circuits of the brain

essentially become waterlogged,

as it were,

and you can't absorb new memories.

So let me show you the data.

Here in this study, we decided
to test the hypothesis

that pulling the all-nighter
was a good idea.

So we took a group of individuals

and we assigned them
to one of two experimental groups:

a sleep group,

and a sleep deprivation group.