We’ve all known people who should have to
wear
a flashing red DANGER! sign if they miss lunch.
We instinctively know to steer clear of someone
who's running on empty. A grumbling stomach
means a drop in blood sugar, and through
excruciating experience, most of us realize that
means trouble.
But could the blood sugar/anger connection lurk
behind more relationship conflicts than we
realize?
A new study probed that question with a
research
methodology as painfully funny as it was
effective. Researchers rounded up 107 married
couples for a 21-day couples’ boot-camp to
draw
a direct line between blood glucose (a.k.a.
circulating blood sugar) and aggression.
First they asked the couples to complete a
questionnaire that evaluated their level of
satisfaction with their marriages, which allowed
the research team to control for variables like
how
rocky a marriage was to begin with. They also
measured all of the participants’ blood glucose
levels to set a benchmark, and continued to
measure the levels throughout the 21-day
study.
The researchers predicted that drops in blood
sugar would consistently correlate with
heightened aggression between the spouses.
They defined aggression in two ways:
aggressive
impulse and aggressive behavior, a distinction
meant to identify aggression in thought versus
action. Aggression rarely happens in a vacuum
—
there’s usually a thought impulse that precedes
it, even if that impulse doesn’t occur
immediately
before the action but compounds over time.
To test aggressive impulse, the researchers
gave
participants a voodoo doll and 51 pins, with
instructions to place as many pins in the doll
every night as needed to show how angry they
were with their spouse. A light conflict day
might
earn just a couple pokes, while a “cover the
kids'
eyes and ears” day might warrant the full 51 to
the head.
To test aggressive behavior, the researchers
had
the spouses wear headphones while they
competed against each other in 25-part tasks.
After each task, the winner decided how loudly
and for how long to blast the loser with a noise
through the headphones.
At the end of the 21 days, with riddled voodoo
dolls and ringing ears aplenty, the researchers'
hypothesis was proven true: The lower the level
of
blood glucose, the more pins the spouses
poked,
and the higher the intensity (and longer the
duration) they blasted their partners through
their headphones.
The study provides a couple of worthwhile
takeaways:
First, quoting lead study author Brad Bushman,
an Ohio State University professor of psychology
and communication, “Before you have a difficult
conversation with your spouse, make sure
you're
not hungry."
Simple to say, harder to do.
Second, and the reason why that’s such good
advice: Our brains are energy hogs. "Even
though
the brain is only two percent of our body
weight,
it consumes about 20 percent of our calories. It
is
a very demanding organ when it comes to
energy," Bushman says.
When the brain is short on energy, it’s also
short
on self-control, opening the door for aggressive
impulses and behavior to take center stage.
And
if the study results are a true indication, we’re
red-lining our self-control more often than we
realize.
I’d love to see a follow-up study that attempts
to
track these results against the blood sugar
rollercoaster associated with fast food-laden
diets.
I have a suspicion that glucose-related
aggression
isn’t solely about how much or little food we
eat,
but also the sorts of food we eat. Just a hunch,
but it stands to reason that shoveling in foods
that cause our blood sugar levels to spike and
crash day after day may also trigger spousal
(and
other) explosions.
A little food for thought while you're sitting in
the
drive-through.
The study was published in the Proceedings of
the National Academy of Sciences.
You can find David DiSalvo on Twitter @
neuronarrative, at his website The Daily
Brain, and on YouTube at Your Brain
Channel. His latest book is Brain Changer:
How Harnessing Your Brain’s Power To
Adapt Can Change Your Life
