The power of the placebo effect - Emma Bryce

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The placebo effect is an unexplained phenomenon wherein drugs, treatments, and therapies that aren’t supposed to have an effect — and are often fake — miraculously make people feel better. What’s going on? Emma Bryce dives into the mystery of placebos’ bizarre benefits.

Lesson by Emma Bryce, animation by Globizco.

In 1996, 56 volunteers took part
in a study

to test a new painkiller called
Trivaricaine.

On each subject, one index finger
was covered in the new painkiller

while the other remained untouched.

Then, both were squeezed
in painful clamps.

The subjects reported that the treated
finger hurt less than the untreated one.

This shouldn't be surprising,

except Trivaricaine wasn't actually
a painkiller,

just a fake concotion
with no pain-easing properties at all.

What made the students so sure
this dummy drug had worked?

The answer lies in the placebo effect,

an unexplained phenomenon

wherein drugs, treatments, and therapies
that aren't supposed to have an effect,

and are often fake,

miraculously make people feel better.

Doctors have used the term placebo
since the 1700s

when they realized the power of
fake drugs to improve people's symptoms.

These were administered when proper drugs
weren't available,

or if someone imagined they were ill.

In fact, the word placebo
means "I shall please" in Latin,

hinting at a history of placating
troubled patients.

Placebos had to mimic the real treatments
in order to be convincing,

so they took the form of sugar pills,

water-filled injections,

and even sham surgeries.

Soon, doctors realized that duping people
in this way had another use:

in clinical trials.

By the 1950s, researchers were using
placebos as a standard tool

to test new treatments.

To evaluate a new drug, for instance,

half the patients in a trial might receive
the real pill.

The other half would get a placebo
that looked the same.

Since patients wouldn't know whether
they'd received the real thing or a dud,

the results wouldn't be biased,

researchers believed.

Then, if the new drug showed a significant
benefit compared to the placebo,

it was proved effective.

Nowadays, it's less common to use placebos
this way because of ethical concerns.

If it's possible to compare a new drug
against an older version,

or another existing drug,

that's preferable to simply giving
someone no treatment at all,

especially if they have a serious ailment.

In these cases, placebos are often used
as a control to fine-tune the trial

so that the effects of the new versus
the old or alternative drug

can be precisely compared.

But of course, we know the placebos
exert their own influence, too.

Thanks to the placebo effect,

patients have experienced relief
from a range of ailments,

including heart problems,

asthma,

and severe pain,

even though all they'd received
was a fake drug or sham surgery.

We're still trying to understand how.

Some believe that instead of being real,

the placebo effect is merely confused
with other factors,

like patients trying to please doctors
by falsely reporting improvements.

On the other hand,

researchers think that if a person
believes a fake treatment is real,

their expectations of recovery actually
do trigger physiological factors

that improve their symptoms.

Placebos seem to be capable of causing
measurable change in blood pressure,

heart rate,

and the release of pain-reducing
chemicals, like endorphins.

That explains why subjects in pain studies
often say placebos ease their discomfort.

Placebos may even reduce levels
of stress hormones,

like adrenaline,

which can slow the harmful effects
of an ailment.

So shouldn't we celebrate
the placebo's bizarre benefits?

Not necessarily.

If somebody believes a fake treatment
has cured them,

they may miss out on drugs
or therapies that are proven to work.

Plus, the positive effects
may fade over time,

and often do.

Placebos also cloud clinical results,

making scientists even
more motivated to discover

how they wield such power over us.

Despite everything we know about
the human body,

there are still some strange
and enduring mysteries,

like the placebo effect.

So what other undiscovered marvels
might we contain?

It's easy to investigate the world
around us

and forget that one of its most
fascinating subjects

lies right behind our eyes.