We all know that we
need sleep and we do know that lack of sleep and increased stress will
interfere with our weight management. I
was reading a report on the BBC news web site which has told us even more
reasons why getting a decent amount of sleep is imperative.
‘Deep sleep sounds
restful, but during it our brains are actually working hard. One of the main
things the brain is doing is moving memories from short-term storage into
long-term storage, allowing us more short-term memory space for the next day.
If you don't get adequate deep sleep then these memories will be lost.’
Memories need to be
consolidated in 24 hours of being formed or they are lost (not great if you are
revising for an exam!)
Deep sleep only
lasts for a few hours, the brain goes through multiple phases of another kind
of activity, called REM sleep.
"This is the
phase when you are usually paralysed - so you can't move," Wulff explained
in the article. But the eye muscles are not paralysed, and that's why it's
called rapid eye movement sleep."
During REM sleep an
extraordinary thing happens. One of the stress-related chemicals in the brain,
noradrenalin, is switched off. It's the only time, day or night, this happens.
It allows us to remain calm while our brains reprocess all the experiences of
the day, helping us come to terms with particularly emotional events.
Drinking alcohol
late at night is not a good idea as it reduces your REM sleep while it's being
processed in your body.
Dr Simon Archer and
his team at Surrey University were particularly interested in looking at the
genes that were switched on or off by
changes in the amount of sleep that people in a controlled experiment had. "We found that overall there were around
500 genes that were affected," Archer explained. "Some which were
going up, and some which were going down."
What they
discovered is that when the volunteers cut back from seven-and-a-half to
six-and-a-half hours' sleep a night, genes that are associated with processes
like inflammation, immune response and response to stress became more active.
The team also saw increases in the activity of genes associated with diabetes
and risk of cancer. The reverse happened when the volunteers added an hour of
sleep.
Fascinating
scientific evidence that sleep really is good for you