The CNN “The Chart” blog reports, “According to two small studies presented” the Associated Professional Sleep Societies annual meeting, “sleep deprivation appears to increase activity in areas of the brain that seek out pleasure – including that provided by junk food.”
In one study, investigators “at Columbia University used functional magnetic resonance imaging (fMRI) … to compare brain activity in 25 volunteers following a normal night’s sleep (about eight hours) and a night in which they were limited to just four hours.”
Participants were shown pictures of both healthy foods and unhealthy foods. The investigators found that “brain networks associated with craving and reward were more active when the participants were sleep-deprived than when they were well-rested – especially when the participants viewed the images of unhealthy foods.”
HealthDay reports, the other study, which also used fMRI, “didn’t find a large difference in the activation of the brain’s reward centers in people who were tired.” The study “did, however, find significantly impaired activity in an area in the frontal lobe of the brain.” The researchers reported that “when people were sleep-deprived and then presented pictures of unhealthy foods, this area of the brain didn’t respond well, which would make choosing healthy foods more difficult.”
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the “peer review” process, in which outside experts scrutinize the data prior to publication in a medical journal.