I'll never forget a line in the classic movie - Journey to the Center of the Earth, when Professor Lindenbrook (James Mason) said he doesn't sleep because he hates those "little slices of death." The irony is deep because sleep is how we stay healthy, and it's divided into an awake stage and four sleep stages.
Stage one sleep is brief and you're still aware. Stage two is light sleep where you're easily roused and it makes up the bulk of sleep. The third stage is deep sleep. Breathing slows, body temperature drops, and muscles relax so the body can repair and rebuild. Stage four is REM or rapid eye movement when emotions and memory are regulated. The brain comes alive with dreams and your heart rate goes up. People cycle through these stages more than once each night with each lasting 50 to 100 minutes.
In the first half of the night, the cycles are more linear while in the second half the cycles are not as defined and involve more light and REM sleep. So, in all, light sleep accounts for half while deep and REM sleep each take up a quarter of sleep.
A recent study of eight thousand people followed for twenty five years found people who slept less than six hours in middle age had a higher risk of dementia. The risk continues beyond age sixty increasing dementia risk by thirty percent for short sleep.
Other studies show it causes the body to produce more Beta (?)-amyloid plaques in the brain which is linked to Alzheimer's. Despite studies that prove we need sleep, most of us still don't make it a priority.
Sounds like a good goal for the new year.
For more information…
The 4 Stages of Sleep
What's happening during NREM and REM sleep...
Sleeping less than 6 hours a night in midlife raises risk of dementia 30%, study finds
Calling all those who are sleep-deprived: We interrupt your yawns with an important announcement.If you're trying to get by on about six hours or less of sleep a night during the workweek, you're setting up your brain for future failure, according to a new study published Tuesday in the journal Nature Communications...