Sleep and why we need it

We all know what it is like to be jet-lagged or sleep deprived and how rubbish it makes us feel. We just cannot respond as well as we should in our befuddled brain fog, craving comforting sweet foods. Well, it turns out there is a good reason for feeling rubbish as if we don’t sleep for the required seven to nine hours we are depriving ourselves of a critical period during which the body needs to repair itself. See the problem if we continually skimp on sleep and prioritise other things over going to bed.

According to TCM (Traditional Chinese Medicine), each organ has a specified time for self-repair. If you continually wake at the same time every night, it could be your body's way of telling you something is not quite right. For example, the liver cleanses the blood and performs a host of functions to rid us of toxins between 1 and 3 am. The small intestine, 12 hours away on the clock to the liver will be at its weakest point at this time. For instance, between 1 - 3 am the liver should be operating at its peak, meanwhile, the small intestine (the organ responsible for the absorption and assimilation of several vital nutrients) is at its lowest point.  

The small intestine is responsible for the absorption of 90% of nutrients.

This is why eating food late at night is not a good idea. Neither the liver nor the small intestine are able to function properly; the small intestine is not able to draw on all available resources for digestion and is distracting those that are being utilised by the liver. Neither is a winner, we are left with poor detoxification and poorly digested food.

Science proves sleep is imperative for a healthy functioning body and to maintain cognitive function. Studies have proven how accidents occur more frequently when we are sleep deprived. Whilst many of us appear to survive on a few hours, the recommended time for an adult is between seven to nine hours. Although as we age these hours sleep may be divided up with an afternoon nap. 

Less than seven hours sleep is equivalent to being a smoker or drinking excess alcohol:

  • It leads to overeating, as the hormone that signals you are full is blunted by lack of sleep.
  • Triggers hunger.
  • Proteins accumulate in the brain which may cause dementia.
  • The brain stops making new memories.
  • In teenagers, it is linked to schizophrenia and depression.
  • Just one night of five hours or less reduces NK cells that reduce cancer by 70%.
  • Less than six hours increases your blood pressure, with a greater risk of heart attack or stroke.
  • If you are male it affects your virility.

What happens during sleep?

During sleep, the brain moves through various different stages; one of these stages is rapid eye movement (REM) sleep. During this phase, the eyes move rapidly in all directions. The other four phases are referred to as non-REM (NREM) sleep. Most dreams occur during REM, which is believed to play a vital part in mood, memory and learning. REM should occur several times throughout the night. The first phase usually lasts about 10 minutes with each stage becoming progressively longer. The final phase lasts for up to an hour. During REM sleep, our brain is almost as active as when we are awake, breathing can become fast and irregular and it is thought memories are consolidated, dreams may also be very vivid. Alcohol before bed reduces the amount of REM sleep. This may impact physical and emotional health as they can both suffer from a lack of REM sleep. 

NREM sleep occurs in four phases and lasts for around two hours, however as we age it can reduce to only 30 minutes. The third phase (previously known as the third and fourth phase) is when the body repairs, regrows tissues, builds bone and muscle, and strengthens the immune system. It is also known as slow-wave sleep (SWS), as we are unresponsive to the environment and do not react to most stimuli. If you happen to be woken during this stage you will feel especially groggy and confused for a few minutes, and it may even affect your mood all day. Another dreamless stage of sleep, it is actually the most likely time for sleepwalking to occur. 

Sleep hygiene

If you have trouble getting to sleep, or experience disturbed sleep you may want to take look at your bedtime routine. Sleep hygiene has never been more important as we are surrounded by blue light from the tv, mobile phone, laptop etc. The average American child has eight appliances giving off light in their bedroom whilst they purportedly sleep!

Why is blue light bad? Blue light interferes with our melatonin, giving the brain the impression that it is not night time, consequently interrupting the body clocks natural rhythm. This can have all sorts of repercussions. 

So what do we do? Establish a bedtime ritual, just as we do for our children, prepare the mind and body for sleep. We need to reduce levels of the hormone cortisol which is linked to stress and anxiety. Cortisol should be at its peak prior to waking, allowing us to jump out of bed but greatly reduced at night enabling its partner melatonin to take the stage.

Melatonin the hormone to promote sleep works on the circadian rhythm, and should increase around two hours before bedtime. However, its arch enemy is blue light, which sends signals to the brain that it is still daytime. If cortisol and melatonin are out of sync, a good night's sleep will be impossible which is why a night time routine is so important.

What to do:

  • Turn the tv off an hour before bed.
  • Listen to calming music.
  • Read a book.
  • Meditate.
  • Journal.
  • Avoid caffeine after lunch.
  • Avoid alcohol and other stimulants.
  • Enjoy a warm bath or shower.
  • Make sure the room is dark.
  • Maintain a regular bedtime and time to wake up, even at weekends.
  • Try to be asleep by 11.00 pm - when your body begins to repair.

If you struggle to get to sleep or suffer from disturbed sleep, it may now be a habit or anxiety or stress may be at the root of the problem. There may be certain key nutrients that may need to be increased in your diet that all have a positive influence on sleep; magnesium muscle relaxant, and reduces cortisol, tryptophan reduces nerve action and is a precursor to melatonin, the sleep hormone. Try to include foods containing these vital nutrients and see if there is a difference.


Institute of Medicine (US) Committee on Sleep Medicine and Research; Colten HR, Altevogt BM, editors. Sleep Disorders and Sleep Deprivation: An Unmet Public Health Problem. Washington (DC): National Academies Press (US); 2006. Available from: doi: 10.17226/11617

Nutritionist Resource is not responsible for the articles published by members. The views expressed are those of the member who wrote the article.

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