December 3 , 2007
For Immediate Release
Contact: Catherine West
(202) 783-2077
cwest@psychologicalscience.org
Got Sugar? Glucose Affects Our Ability to Resist Temptation
New
research from a lab at Florida State University reveals that
self-control takes fuel-- literally. When we exercise it, resisting
temptations to misbehave, our fuel tank is depleted, making subsequent
efforts at self-control more difficult.
Florida State
psychologist Roy F. Baumeister and his colleagues Kathleen D. Vohs,
University of Minnesota, and Dianne M. Tice, Florida State, showed this
with an experiment using the Stroop task, a famous way of testing
strength of self-control. Participants in this task are shown color
words that are printed in different-colored ink (like the word
red
printed in blue font), and are told to name the color of the ink, not
the word. Baumeister found that when participants perform multiple
self-control tasks like the Stroop test in a row, they do worse over
time. Thus, the ability to control ourselves wanes as it is exercised.
Moreover,
Baumeister and colleagues found that the fuel that powers this ability
turns out to be one of the same things that fuels our muscles: sugar,
in the form of glucose.
The researchers measured the
blood glucose levels of participants before either engaging in another
self-control task or a task that did not involve self-control. They
found that the group performing the self-control task suffered
depletion in glucose afterward. Furthermore, in another experiment, two
groups performed the Stroop task two times each, drinking one of two
sweetened beverages in between. The control group drank lemonade with
Splenda, a sugar-free sweetener; the test group got lemonade sweetened
with real sugar. The sugar group performed better than the Splenda
group on their second Stroop test, presumably because their blood sugar
had been replenished.
The results as reported in the December issue of
Current Directions in Psychological Science,
a journal of the Association for Psychological Science, suggest the
possibility of psychological interventions for helping people achieve
greater self-control. For one thing, like muscles, self-control may be
able to be strengthened through exercise. Results so far are
inconsistent, Baumeister says, and some regimens work better than
others, but he envisions that greater understanding of the biological
and psychological underpinnings of our ability to control ourselves
will have important real-world application for people in the
self-control business, such as coaches, therapists, teachers, and
parents.
Author Contact: Roy Baumeister baumeister@psy.fsu.edu
# # #
Current Directions in Psychological Science
publishes concise reviews on the latest advances in theory and research
spanning all of scientific psychology and its applications. For a copy
of the article “The Strength Model of Self-Control” and access to other
Current Directions in Psychological Science research findings, please contact Catherine West at (202) 783-2077 or cwest@psychologicalscience.org.
