This piece of advice comes from Matthew Walker, a professor of psychology and neuroscience at UC Berkeley, as reported at The Atlantic Monthly website:
“I think you have about 16 hours of optimal functioning before the brain needs to go offline and sleep,” Walker told Anahad O’Connor at The New York Times. “It’s the single most effective thing people can do every day to reset their brain and body health.”
Walker is the lead author of a recent study on sleep which looked at its relation to food preferences (and, by implication, weight gain). According to The Atlantic, the study:
looked at real-time brain imaging while people ate different kinds of food while sleep-deprived and rested. It found that “reward centers” in our brains seem to respond more strongly to fatty and sweet foods when we are sleep-deprived. We also generally make less “rational” (more impulsive) decisions when we’re sleep-deprived, and this study showed that insular and frontal cortices that regulate “food desirability choices” were visibly less active when we haven’t slept.
Here’s my reading of this: when you’re sleep deprived, your glucocorticoid hormones get elevated (effecting levels of blood glucose, inflammation, stress, etc.) and your prefrontal cortex, acting as a kind of Freudian superego repressing your emotional limbic “id” system, doesn’t function well, and so you do things you might not otherwise (like eat bad foods or engage in unprotected sex).
Unprotected sex? How did that get into this post? I’m thinking of Daft Punk and Stephen Colbert staying “up all night to get lucky.” Sorry.