Obesity linked to sleep loss and food choices

Loss of sleep impairs brain regions where food choices are made, explaining the link between sleep loss and obesity.

WASHINGTON: Loss of sleep impairs brain regions where food choices are made, possibly helping explain the linkage between sleep loss and obesity.

A group of healthy adults participated in two sessions using functional magnetic resonance imaging (fMRI), one after a normal night's sleep and a second after a night of sleep deprivation.

In both sessions, participants rated how much they wanted various food items shown to them while they were inside the scanner.

"Our goal was to see if specific regions of the brain associated with food processing were disrupted by sleep deprivation," said Stephanie Greer, graduate student at the Sleep and Neuroimaging Lab at the University of California, Berkeley, who led the study.

Results show that sleep deprivation significantly impaired brain activity in the frontal lobe, a region critical for controlling behaviour and making complex choices, such as which foods to eat, according to a California statement.

The study suggests that sleep loss may prevent the higher brain functions, normally critical for making appropriate food choices, rather than necessarily changing activity in deeper brain structures that react to basic desire.

"It seems to be about the regions higher up in the brain, specifically within the frontal lobe, failing to integrate all the different signals that help us normally make wise choices about what we should eat," Greer added.

She added that this failure of the frontal lobe to optimally gather the information needed to decide on the right types of foods to eat - such as how healthy relative to how tasty an item may be - may represent one brain mechanism explaining the link between sleep loss and obesity.

These findings were presented at the SLEEP 2012, the 26th annual meeting of the Associated Professional Sleep Societies (APSS) in Boston, US.