Erin Hanlon, University of Chicago – Sleep Munchies

Not getting enough sleep carries an increased risk of obesity.

Erin Hanlon, Research Associate (in rank of Assistant Professor) at the University of Chicago, explains that lack of sleep can make your body go haywire, causing you to want to overeat.

Erin C. Hanlon, Ph.D. is a Research Associate in the Sleep, Metabolism, and Health Center and the Department of Medicine at the University of Chicago. As a behavioral neuroscientist, she is interested in the relationship between behavior, brain mechanisms, and physiology that may impact human health. Primary research interests have included the detrimental effects of sleep loss and how sleep benefits health. In particular, she has focused on the effect of sleep restriction on brain reward and feeding systems as well as peripheral metabolic systems in both rodent and human models.

Sleep Munchies

Evidence from both laboratory and epidemiologic studies has consistently associated insufficient sleep or short sleep with increased risk of obesity. Carefully controlled laboratory studies of systematic sleep restriction in healthy adults have reported impaired glucose metabolism, alterations in peripherally secreted hormones that modulate feeding, increased subjective appetite and hunger ratings, greatest for high carbohydrate and high fat foods, and increased actual consumption of snacks and high energy foods.  We wanted to examine novel potential mechanisms that might further help explain the association between short sleep and obesity. 

The endocannabinoid system includes lipids that are made in your body and the system is involved in many things including stress, the immune system, pain, and reward.   Much attention has been paid in recent years to the ability of the endocannabinoid system to control feeding, appetite, and energy homeostasis.  In our current study, we’ve focused on the endocannabinoid systems involvement in hedonic eating – or eating for the pleasurable aspect. 

In 14 individuals, we examined serum endocannbinoid levels over a 24hr period, which included either 8.5hrs or 4.5hrs of sleep. We found following normal sleep there was a clear circadian rhythm with a nadir around mid-sleep and a peak in the early afternoon.  Sleep restriction significantly increased the amplitude of the rhythm due to an increase in the peak levels.  The increase was delayed and remained elevated until the evening.  Following sleep restriction, these individuals report increases in hunger and a stronger desire to eat, along with an inability to inhibit snack consumption, corresponding to the same time as elevated endocannabinoid levels. 

These data suggests that elevation of peak daytime levels of endocannabinoids may contribute to the risk of overeating associated with sleep restriction, particularly driving reward related eating, and present a novel mechanism by which sleep restriction may be associated with obesity.