artikel tentang obesitas

OBESITY TIED TO
MEMORY LOSS
By Rick
Nauert PhDSenior News Editor
Reviewed by John M. Grohol, Psy.D. on August 26, 2009
Obesity has become a significant
health crisis: More than 300 million people worldwide are considered obese and
more than a billion people are classified as overweight.
Obesity is associated with the
development of illnesses including cardiovascular disease, Type II diabetes,
and hypertension. New research suggests the ill effects of obesity may not stop
with these physical maladies, however; mental health may be affected as well.
In the current online edition of the
journal Human Brain Mapping, Paul Thompson, senior author and a UCLA
professor of neurology, and lead author Cyrus A. Raji, a medical student at the
University of Pittsburgh School of Medicine, and colleagues compared the brains
of people who were obese, overweight, and of normal weight, to see if they had
differences in brain structure.
They found that obese people had 8
percent less brain tissue than normal-weight people, while overweight people
had 4 percent less tissue. According to Thompson, who is also a member of
UCLA’s Laboratory of Neuro Imaging, this is the first time anyone has
established a link between being overweight and having what he describes as
“severe brain degeneration.”
“That’s a big loss of tissue and it
depletes your cognitive reserves, putting you at much greater risk of
Alzheimer’s and other diseases that attack the brain,” said Thompson. “But you
can greatly reduce your risk for Alzheimer’s, if you can eat healthily and keep
your weight under control.”
The researchers used brain images
from an earlier study called the Cardiovascular Health Study Cognition Study.
Scans were selected of 94 elderly people in their 70s who were
healthy—not cognitively
impaired—five years after the scan was taken.
To define the weight categories,
they used the Body Mass Index (BMI), the most widely used measurement for
obesity. Normal weight people were defined as having a BMI between 18.5-25;
overweight people between 25-30, and obese people greater than 30.
The researchers then converted the
scans into detailed three-dimensional images using tensor-based morphometry, a
neuroimaging method that offers high resolution mapping of anatomical
differences in the brain.
In looking at both gray matter and
white matter of the brain, they found that the people defined as obese had lost
brain tissue in the frontal and temporal lobes, areas of the brain
critical for planning and memory, and in the anterior cingulate gyrus
(attention and
executive functions), hippocampus (long-term memory) and basal ganglia
(movement).
Overweight people showed brain loss
in the basal ganglia, the corona radiata, white matter comprised of axons, and
the parietal lobe (sensory lobe).
“The brains of obese people looked
16 years older than the brains of those who were lean, and in overweight people
looked eight years older,” says Thompson.
“It seems that along with increased
risk for health problems such as type 2 diabetes and heart disease, obesity is
bad for your brain: we have linked it to shrinkage of brain areas that are also
targeted by Alzheimer’s,” said Pittsburgh’s Raji.
“But that could mean exercising,
eating right and keeping weight under control can maintain brain health with
aging and potentially lower the risk for Alzheimer’s and other dementias.”
Source: UCLA