Search
UK
US
India
Smarter Revision
Parents
Students
Tutors
Teachers
Knowledge Bank
Survey Results
Join Us
Login
UK
US
India
Search
Join Us
Login
KS1
(Age 5-7)
KS2
(Age 7-11)
11 Plus
(Age 7-11)
KS3
(Age 11-14)
GCSE
(Age 14-17)
PSHE
A.I.
ESL
Spanish
Specialist
Games
Home
Knowledge Bank
Essential Facts About...
50 Essential Facts About Sleep
50 Essential Facts About Sleep
The 50 facts that you MUST know on your way to becoming a sleep expert!
Adults need between 7 and 9 hours sleep per night
Amount
Former PM Margaret Thatcher claimed to need only 4 hours sleep a night
The average person takes about 15 minutes to fall asleep
Women tend to need more sleep than men
Newborn babies sleep for between 14 to 17 hours a day
Insomnia is the most common sleep disorder
Disorders
Sleep apnoea is a disorder that stops you from breathing as you sleep
Narcolepsy is a disorder which sends people to sleep at almost any time
Restless legs syndrome causes people to move their legs during sleep
Parasomnias are a group of disorders which cause unpleasant effects in sleep
We spend about 2 hours dreaming every night
Dreams
We forget almost all our dreams soon after we wake
We can't be sure if animals dream but it seems likely that they do
"Lucid" dreams are ones you can control. Not many of us can do this
Some blind people, even if blind from birth, dream in pictures
The technical name for sleepwalking is somnambulism
Somnambulism
Most of us have sleepwalked at some point
Contrary to popular belief it is not dangerous to wake a sleepwalker
Sleepwalking tends to run in families
The only danger in sleepwalking is the potential for accidents
Sleeping longer is not necessarily a good thing
Myths
Older people do not need less sleep than young adults
Our brains do not shut down when we are asleep
Sleeping in at the weekend does not make up for lost sleep
Daytime naps are a good idea if you are feeling tired
Before the Industrial Revolution we had 2 sleeps per night
History
Descartes believed that sleep was hydraulic
The Ancient Greeks thought that sleep was caused by our blood
They also slept in temples to receive messages from the gods
In the middle ages it was thought dreams came from either God or Satan
The most common nightmares involve physical aggression
Nightmares
Sadness, confusion and guilt are more common than fear in nightmares
Most of us have occasional nightmares. Some of us have them regularly
Eating cheese before bed will not give you nightmares
The word "nightmare" comes from Old English "mare", meaning a demon
Scientists still don't know why we need to sleep
Science
The longest time anyone has gone without sleep is 11 days
If you struggle to get out of bed in the morning you may have dysania
Almost half of us sleep in the foetal position
12% of people dream entirely in black and white
Poor sleep is linked to higher body weight
Health
Poor sleepers have a greater risk of heart disease and strokes
Poor sleep is also linked to diabetes
Lack of sleep can be caused by and can cause depression
Our immune systems are weakened if we do not get enough sleep
The Chernobyl disaster is thought to have been caused by sleep deprivation
Accidents
The Challenger space shuttle disaster involved staff who had 2 hours sleep
Sleepwalking has been used as a defence in murder trials
A German climbed out of a window and fell 7 storeys while sleepwalking
An American man shot himself while he was asleep!