Facts About Sleep


Famous investor Warren Buffet apparently values highly a good night of sleep, once saying:
"When forced to choose, I will not trade even a night's sleep for the chance of extra profits."
But you don’t need megabucks to understand the value of quality sleep. Most human beings instinctively know that sleep is vital to a normal existence, and most of us happily spend nearly a third of our lives in a sleeping state. But that may be all many of us know about sleep.
Compared to its pursuit of other topics, science was relatively late in making sleep a major field of study. But sleep researchers are now uncovering some of the mysteries of the sleeping state. Check out these sleep facts:

  • Sleep problems are estimated to affect about 70 million Americans or every age, race, and socioeconomic level.
  • In 1910, most people slept 9 hours a night, but recent surveys show the average adult now sleeps fewer than 7 hours.

Facts About Sleep

  • Sleep allows the brain to form pathways necessary for learning and creating memories and new insights.
  • Sleep is divided into two stages: rapid eye movement (REM) sleep and non-REM sleep, which has three stages, ending in deep sleep.
  • Deep sleep is considered the “restorative” sleep necessary for feeling well-rested and energetic during the day.
  • Science is learning that a chronic lack of sleep increases the risk of obesity, diabetes, cardiovascular disease and infections.
  • When people who lack sleep are tested on a driving simulator, they perform just as poorly as people who are drunk.
  • One study found that one-fifth of night shift workers had a car crash or near-miss in the preceding year because of sleepiness on the way home from work.
  • A study showed when healthy young men slept only 4 hours a night, their insulin and blood sugar levels matched those seen in people who were developing diabetes.
  • One study suggests sleep is needed for creative problem-solving. Author Mary Shelley said the idea for her Frankenstein novel came from a dream.
  • Dreaming occurs in REM sleep, when the mind is active and the body occasionally is in motion.
  • During non-REM sleep, your heart rate and blood pressure progressively slow.
  • Stage 3 non-REM sleep triggers the release of growth hormones, contributing to growth in children and boosting the repair of cells for people of all ages.
  • In one study, sleep-deprived volunteers given the flu vaccine produced less than half as many flu antibodies as those who were well rested and given the vaccine.
  • Naps are not a waste of time, but they are no substitute for a good night’s sleep. Avoid taking them after 3 p.m.
  • Do not lie in bed awake. If you cannot sleep after 20 minutes, get up and do some relaxing activity until you feel tired.
Age Recommended Amount of Sleep
Newborns 16–18 hours a day
Preschool-aged children 11–12 hours a day
School-aged children At least 10 hours a day
Teens 9–10 hours a day
Adults (including the elderly) 7–8 hours a day