Sitting Is Bad for Your Brain – Not Just Your Metabolism or Heart:
Sitting, like smoking, increases the risk of heart disease, diabetes and premature death. Researchers at UCLA wanted to see how sedentary behavior influences brain health, especially regions of the brain that are critical to memory formation.
FINDINGS
Sitting too much is linked to changes in a section of
the brain that is critical for memory, according to a preliminary study
by UCLA researchers of middle-aged and older adults.
BACKGROUND
Studies
show that too much sitting, like smoking, increases the risk of heart
disease, diabetes and premature death. Researchers at UCLA wanted to see
how sedentary behavior influences brain health, especially regions of
the brain that are critical to memory formation.
METHOD
UCLA
researchers recruited 35 people ages 45 to 75 and asked about their
physical activity levels and the average number of hours per day they
spent sitting over the previous week. Each person had a high-resolution
MRI scan, which provides a detailed look at the medial temporal lobe, or
MTL, a brain region involved in the formation of new memories.
The
researchers found that sedentary behavior is a significant predictor of
thinning of the MTL and that physical activity, even at high levels, is
insufficient to offset the harmful effects of sitting for extended
periods.
This study does not prove that too much sitting causes
thinner brain structures, but instead that more hours spent sitting are
associated with thinner regions, researchers said. In addition, the
researchers focused on the hours spent sitting, but did not ask
participants if they took breaks during this time.
The researchers
next hope to follow a group of people for a longer duration to
determine if sitting causes the thinning and what role gender, race, and
weight might play in brain health related to sitting.
IMPACT
MTL
thinning can be a precursor to cognitive decline and dementia in
middle-aged and older adults. Reducing sedentary behavior may be a
possible target for interventions designed to improve brain health in
people at risk for Alzheimer’s disease, researchers said.
AUTHORS
Prabha
Siddarth, a biostatistician at the Semel Institute for Neuroscience and
Human Behavior at UCLA, is the study’s first author. Dr. David Merrill,
a geriatric psychiatrist and assistant clinical professor of psychiatry
and biobehavioral sciences at UCLA, is the study’s senior author. The
other authors are Alison Burggren and Dr. Gary Small, both of UCLA, and
Harris Eyre of the University of Adelaide, Australia.