3 scientists just won the Nobel Prize for discovering how body clocks are regulated — here’s why that’s such a big deal


insomnia sleep  womanStokkete/Shutterstock


  • Jeffrey C. Hall, Michael Rosbash, and Michael W. Young
    were
    awarded the 2017 Nobel Prize in Physiology or Medicine
    “for
    their discoveries of molecular mechanisms controlling the
    circadian rhythm.”
  • Your circadian rhythm (or internal body clock) helps
    regulate when you feel awake or asleep — and much
    more.
  • Going against that body clock goes against
    your biology and has serious consequences for
    health.

The thing that makes you a “morning person” or a “night owl”
isn’t an arbitrary preference or tendency. It’s something
that’s fundamentally part of your biological makeup — and
something that we ignore at our own peril.

On October 2, Jeffrey C. Hall, Michael Rosbash, and Michael W.
Young were
awarded the 2017 Nobel Prize in Physiology or Medicine
“for
their discoveries of molecular mechanisms controlling the
circadian rhythm.”

In other words, these researchers played a key role in
identifying how cells in organisms regulate the internal
body clock — also known as the chronotype or circadian rhythm —
which determines when people feel awake or sleepy.

This is a Nobel Prize-winning discovery because it shows how
biology regulates body clocks for living organisms ranging from
fruit flies (which these researchers originally worked with) to
humans.

Chronobiologists, who study this kind of science, emphasize the
importance of the discovery because it’s only after
accepting body clocks as a biological fact that you can
fully appreciate how big a role they play in our health. Our body
clocks have huge effects on everything from cancer risk
to mental health to obesity.

“[S]ome people still think the body clock is something esoteric
rather than a profoundly biological function,” chronobiologist
Till Roenneberg wrote in his book “Internal
Time: Chronotypes, Social Jet Lag, and Why You’re So Tired
,”
in a section explaining some of Robash’s work with fruit flies.

Some think the biological clock is only an issue for “sensitive
people,” Roenneberg writes, explaining why it’s a common
sentiment that it’s possible for people to just change their
natural rhythms to fit a schedule that a job or school may
require — even though we know that biological clocks can only be
changed to a limited degree, and for some people can’t really be
shifted much at all.

“Yet the biological details, right down to the molecular and
genetic levels, prove how much biology is behind our internal
timing system.”


press figure1
Even
plants have body clocks. They open during the day and close at
night, but Jean Jacques d’Ortous de Mairan found that even plants
kept in constant darkness continue to follow a similar rhythm,
since their internal biology dictates it.


Nobel
Prize



Night and day on a genetic level

As a press release from the Nobel Committee explains,
the three Nobel laureates first isolated the “clock gene”
known as the “period gene” that regulates the internal clock of
fruit flies in 1984 (the gene had been discovered but not
specifically isolated in the 1970s).

Hall and Rosbash discovered that this gene played a role in
causing cells to produce what they named the “PER” protein, which
accumulated throughout the night before breaking down during the
day. They figured out that the period gene would cause the PER
protein to build up until it hit a high enough accumulation that
it switched off the period gene. Once protein levels degraded
enough, the gene would switch back on, coding for more protein
production.

Young found a second clock gene in 1994, called “timeless,”
which created a protein that bound with the PER protein,
giving it the ability to enter the cell nucleus to then block
activity. Another gene he discovered helped regulate this process
to basically match a 24-hour cycle.

Other aspects of biology help regulate this internal clock as
well, including hormones and other genes.

Light plays a crucial role, helping trigger phases of the body
clock. It’s also the reason why we all have an internal
clock in the first place.

As biological creatures, we can’t all be at peak energy
throughout the day. Sometimes, we need to be on high alert and
able to react quickly. At other times, we need to eat, rest, and
sleep to regain energy. Our body clock regulates these phases,
which is why most of us sleep at night and are awake during the
day — though
there’s significant variation between individuals
as to when
we feel most awake and most asleep, regulated by genetics and
other factors.


press figure3
How
a fairly typical human circadian rhythm works.


Nobel
Prize



Understanding that there is a physical cycle and that there are
biological factors that all work together helps explain why it’s
hard to suddenly pull all-nighters, adjust to a new time zone, or
start waking up earlier: Your entire body, down to your
cells, needs time to adapt.

Deadly consequences for ignoring the clock

Having an internal clock naturally keeps us to a schedule. It
isn’t always the schedule we “want,” since
some of us are night people and others morning people
.

But it’s at least a schedule that defines when we’ll be
sleepy, when we’ll be hungry and best process food, when we’ll be
most mentally alert, and when we’ll be most physically capable.

It’s when our lives aren’t properly matched with our body clocks
that things start to go haywire. Night shift work and exposure to
bright light at night (which can start to shift the body
clock) can cause a sort of internal jet lag. The same things
happens when flying to a new place.

The biggest problems are for people whose schedule changes
regularly, making it impossible to have consistency. 

People who don’t have a regular schedule gain weight more easily,
are more likely to suffer from mental illness like anxiety or
depression, and undergo biological changes significant enough
that the International Agency for Research on Cancer classifies
shift work
as a “probable human carcinogen.”

That’s why, more than anything else, sleep researchers say having
a regular schedule is key.

Trying to match your life to your circadian rhythm isn’t just a
matter of preference. It’s an issue of biology, and one that
could explain why on a certain schedule you thrive and on another
schedule, everything feels wrong.


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