Sleep deprivation, either from regularly not allowing enough time for sleep or due to a physical or mental problem that prevents restful sleep, produces noticeable symptoms, including the following:1
- Feeling drowsy during the day
- Routinely falling asleep within only 5 minutes of lying down in bed for the night
- Experiencing “microsleeps,” which are very brief episodes of sleep while being awake
Sleep deprivation can noticeably affect people’s performance, including their ability to think clearly, react quickly, and form memories. Sleep deprivation also affects mood, leading to irritability; problems with relationships, especially for children and teenagers; and depression. Sleep deprivation can also increase anxiety.3
Sleep is important for overall health, and inadequate sleep is associated with numerous health problems. Research shows that not getting enough sleep, or getting poor-quality sleep, increases the risk of high blood pressure, heart disease, obesity, and diabetes.
Sleep deprivation can also be very dangerous. Sleep-deprived people who were tested using a driving simulator or performing hand-eye coordination tasks did as badly as, or worse than, people who were intoxicated.7 Drowsy driving causes thousands of car crashes each year, some of them fatal.8
Sleep deprivation magnifies the effect of alcohol on the body. A fatigued person who drinks will be more impaired than a well-rested person.