Sleep well, or face the possibility of eating poorly

It’s probably easier to fill a plate with nutritious food at a buffet if you’ve had enough sleep -- and not just because you might be more attentive.

Sleep deprivation has been associated with obesity, but researchers still are learning exactly what’s going on. Two research projects presented at this week’s annual sleep conference looked at what happens in the brain when a sleep-deprived person is considering: Apple? Chips?

In one of the studies, 16 healthy adults underwent fMRIs – functional magnetic resonance imaging – after a normal night’s sleep and after 24 hours of sleep deprivation. While they were in the scanner, they rated how much they wanted 80 food items, lead researcher Stephanie Greer said by phone.

After the scan, participants got the food they chose; that gave the decision more weight than just selecting a picture of a food, said Matt Walker, a UC Berkeley psychology professor.

The study is looking at the neural systems of the brain to see how they affect the decisions made.

“It seems to be about the regions higher up in the brain, specifically within the front lobe, failing to integrate all the different signals that help us normally make wise choices about what we should eat,” Greer said in a statement.

The study also showed that in sleep-deprived people factors of taste and health were less at work, said Greer, who presented her work this week at the 26th annual meeting of the Associated Professional Sleep Societies in Boston.

The second study looked at how the brain perceived healthful and unhealthful foods.

In that study, researchers from St. Luke’s-Roosevelt Hospital Center and Columbia University in New York also used fMRI, with people who had slept for four hours a night for five nights, or for up to nine hours a night for five nights. They looked at the brain images of 25 people while those people looked at images of healthful and unhealthful foods.

“The unhealthy food response was a neuronal pattern specific to restricted sleep. This may suggest greater propensity to succumb to unhealthy foods when one is sleep-restricted,” Marie-Pierre St-Onge, the study’s principal investigator, said in a statement.

The participants ate more overall and more fat after being sleep-deprived, St-Onge said.

Previous research has shown a link between sleep loss and obesity through changes in appetite and hormone regulation.

“We’ve known for a good while that sleep deprivation has an effect on obesity,” said William Kohler, medical director of the Florida Sleep Institute in Spring Hill, Fla. These studies provide “additional objective evidence that sleep and the lack of it have practical consequences.”