Lack of sleep affects physiological and cognitive functions such as memory and attention, complex thought, motor response and emotional control.
One particular study showed that participants kept awake for up to 19 hours scored substantially worse on performance and alertness than those who were legally intoxicated.
(Source: National Sleep Foundation – Sleep-Wake Cycle, 2006)
Lack of sleep also causes us to feel pretty miserable, and studies have shown that it considerably affects mood, causing anger, anxiety and sadness.
But sleep loss does far more than make us feel grumpy, sad and a little slower. In the past few years, investigators have found that sleep loss may have harmful consequences for our immune system, contributing to serious illnesses such as obesity, diabetes, and hypertension.