Recent research presented at the Cognitive Neuroscience Society has found that the olfactory system kicks into overdrive when you’ve had less sleep. 

Scientists from Northwestern University found that adults showed significantly greater brain activity in their olfactory areas after 4 hours of sleep as compared to after 8 hours of sleep. The response was seen only for food smells like potato chips and cinnamon rolls – but not for non-food smells like pine trees. 

Researchers believe this finding may be one more piece in the puzzle connecting stress, sleep deprivation, and overeating. You can view the study abstract here