If you work third shift, pull all-nighters (studying or watching a TV show) or experience jetlag, your clock might be off.
Circadian rhythm, the name given to your body’s 24-hour internal clock, controls your body’s sleep-wake cycle.
“It’s not just for sleep,” says behavioral sleep medicine psychologist Alicia Roth, PhD. “It’s for everything that goes on in our body. We have internal clocks for our hormones, our immune system, our digestion. Our organs all run on some sort of timing system.