I came across several great studies from Tufts University and this is just another good reason to get enough sleep!
“To eat right tomorrow, get a good night’s sleep tonight. Two studies presented at the annual meeting of the Associated Professional Sleep Societies report that sleep-deprived subjects show brain changes that affect their decision-making and predispose them to poor dietary choices. Both were crossover studies, in which 23 and 25 healthy subjects were tested after being shorted on sleep and after sleeping normally; both used functional magnetic resonance imaging (MRI) to study brain activity. The first study compared sleeping normally with staying up all night, with snacks at 2:30 a.m. and breakfast at 8:30 a.m. Participants were then quizzed about food desires and given MRI scans. When subjects were well-rested, the scans showed greater frontal-lobe activity in areas indicative of decision making. The second study compared 6 days of sleep deprivation with normal sleep. When sleep deprived, subjects responded to fatty, sugary foods with brain activity much like that in studies of the obese.”