Sleep, what’s it all about then? If you have laid in bed, tossing and turning, unable to sleep then you might have asked this question to yourself on many occasions. The answer should be obvious but we really don’t know exactly. For those people who can’t sleep it is of little value to know that simply put, getting the right sleep is essential to help the body and brain function properly and lack of sleep can have devastating effects on mind and body.
It has long been understood that during periods of sleep the body mends and repairs itself, which indeed it does but in fact it is now believed that normal relaxation does the same or a similar job.
Besides, during sleep you are likely to be on the move betwen 20 and 40 times a night and certainly the brain remains active also, processing memories and emotions or what I like to think of as “housekeeping”.
Effects of Sleep Deprivation
Without a night of restful sleep you can simply feel rubbish during the day but after a few nights or more of sleep loss you can experience a whole range of physical and mental effects.
Sleep deprivation effects include a higher risk of depression, stroke, heart disease and type 2 diabetes.
And for example, sleep deprivation studies have shown that women who get less than 6 hours sleep a night are more likely of developing breast cancer than a women who gets 7 hours.
So as well as the immune system, the heart and circulatory system lack of sleep can also affect the hormonal system with the result that sufferers tend to eat possibly one and a half times more than good sleepers.
This may cause a vicious circle with obesity being one of the prominent causes for sleep apnoea.
Other symptoms of insomnia are a lowering of the immune system making you more likely to get infections, an impairment of co-ordination and judgement, certainly making you more dangerous on the roads, moodiness, causing relationship issues at home and work and overall a chronic lack of sleep is thought to overall lower your life expectancy.
So something needs to be done if you’re not getting the right sleep.
Stages of Sleep
There are 2 types of sleep REM (rapid eye movement) and NREM (non rapid eye movement which occurs within 5 stages of sleep which then constitutes a cycle lasting for around 90 minutes.
The first cycle begins with stage 1 NREM when you’re sleeping lightly. Stage 2 NREM follows when you’re arousal level is higher and lasts for 10 to 25 minutes. Stages 3 and 4 of NREM or slow wave sleep takes around 20 to 40 minutes in the first cycle. Stage 5 is REM sleep and lasts for about 5 to 10 minutes in the first cycle and around 60 minutes in the last.
So stages 1 and 2 can be seen as the slowing down of body functions in preparation for stages 3 and 4, slow wave sleep, in which your blood pressure and body temperature falls, your breathing slows down and your kidneys function is reduced, producing less urine. During these stages growth hormones are released aiding in the repair and maintenance of the body tissues and immune system.
Stage 5, REM sleep is characterised by the eyes darting all over the place. Your breathing rate increases along with your heart rate and blood pressure and the brain is as acitve as it is when you’re awake, however your muscles are temporarily paralized. This may be to prevent you acting out your dreams.
Your dreams are the manifestations of memories and experiences that are being processed and stored. This is why it is thought that too little sleep can affect memory.
Although you dream in REM sleep it is not as deep or satisfying as in deep sleep, stages 3 and 4.