Sleepiness in America might be destroying high calorie food inhibitions
Researchers suggest sleepiness, which is prevalent among Americans, could be driving high calorie eating behaviors, contributing to obesity. Lack of adequate sleep contributes to impaired metabolic activity, shown in past studies and now researchers say feeling drowsy during the day impairs the brain’s ability to make sensible, low calorie food choices.
In a new study, scientists found feeling sleepy impairs the brain's ability to control response to high calorie foods that was especially evident in women.
Scientists suggest chronic sleep deprivation that is typical of westernized countries could be a key player in rising obesity rates.
Daytime sleepiness blunts inhibitions in the pre-frontal cortex of the brain related to food intake. The same area of the brain is thought to be responsible for reduced metabolic activity from daytime drowsiness.
Is our sleepy society driving obesity?
A 2010 study titled "More Adults Report Excessive Sleepiness in the U.S. than in Europe", from the American Academy of Sleep Medicine found excessive sleepiness is more prevalent in the U.S. than in Europe. The study was published May, 2010, authored by
Feeling sleepy during the day, according to the 2010 report, is more prevalent among women. An estimated 19.5 percent of individuals in the U.S. report feeling moderately or excessively drowsy during the day, raising concerns about the public health implications.
In the current study, researchers used fMRI (functional magnetic resonance imaging) to map the brain’s response to enticing, high calorie foods, matching study participant’s responses with self-reported levels of daytime sleepiness. As a control, images of plants and rocks were shown to the participants.
Levels of perceived drowsiness was measured in 12 healthy men and women between the ages of 19 and 45 years, using the Epworth Sleepiness Scale that gauges the likelihood of dozing off when sitting, watching television or reading.
"Self-reported daytime sleepiness among healthy, normally rested individuals correlated with reduced responsiveness of inhibitory brain regions when confronted with images of highly appetizing foods," said principal investigator William Killgore, PhD, assistant professor of psychology at Harvard Medical School and McLean Hospital in Belmont, Mass.
In past studied Kilgore found women’s prefrontal cortex is highly activated in response to high calorie enticing foods, compared to men.
"It suggests that even normal fluctuations in sleepiness may be capable of altering brain responses that are important for regulating dietary intake, potentially affecting the types of choices that individuals make when selecting whether and what to eat."
The study suggests sleepiness that is prevalent in the U.S. could be driving high calorie food choices and obesity. The authors say more studies are needed to find out if the study results mean high calorie food consumption increases when the prefrontal cortex is stimulated during daytime drowsy states.
Kilgore notes it is important to understand what happens in the brain that relates to food choices. The parallel between rising obesity rates in America and increased sleepiness, shown in the study to excite areas of the brain related to images of high calorie foods, could have public health implications that should be further explored.
:Daytime Sleepiness is Associated with Altered
Brain Activation During Visual Perception of
High-Calorie foods: An fMRI Study:
Weiner MR, Schwab ZJ, Killgore W