Adults need 7 or more hours of SLEEP per night for best health and well-being. Short sleep duration is defined as less than 7 hours of sleep per 24-hour period. Signs of getting enough sleep include feeling refreshed upon waking and not being too sleepy during the day. Health care workers report sleeping 6 hours or less per day,14 which sleep experts consider too little.
Most adults need 7-8 hours of good quality sleep per night (good quality means that the main sleep episode does not have frequent awakenings and is long enough for the individual). Most people who say they do not need many hours of sleep force themselves to sleep less and, as a result, struggle to stay awake and function during the day. People who need several cups of coffee a day to feel alert may not be getting enough good quality sleep. The Epworth Sleepiness Scale, shown on the next page, is a self-administered test that you can use to estimate your usual level of wakefulness sleepiness compared to sleepiness that may be a cause for concern.
One way to estimate your need for sleep duration is to observe how long you sleep towards the end of a relaxing two-week holiday, when you are not under time pressure and sleep freely (wake up spontaneously, without alarm, and go to bed when tired).