Sleep deprivation and sleep debt

Sleep deprivation and sleep debt

Sleep Centre

Sleep deprivation and sleep debt

There are many misconceptions about how much sleep individuals need or can do without. Unfortunately, few realise that lack of sleep slowly but surely builds up to what is known as a “sleep debt”.

Sleep is a prerequisite to health

Scientists point out that getting enough sleep is not an option but a necessity. Not only does your body need it but so does your brain. While you are sleeping important biological and physiological processes are taking place in your body and brain; processes that influence your overall health and wellbeing and specifically your daytime performance either negatively (if a sleep debt has built up) or positively (see article Sleep, wonderful sleep).

Sleep debt

Prolonged sleep deprivation has been used as a form of torture for centuries as it can cause a state of paranoia, hallucination and disorientation, and in extreme cases death! The moment your body and brain’s sleep needs are not met, a sleep debt starts building up, a debt that will exact payment one way or another.

Some of these payment options may include the following:

Impaired reasoning and functioning skills
Burning the candle at both ends and the fatigue, sleepiness, difficulty concentrating and impaired reasoning and functioning skills associated with this state have been the cause of many major disasters in recent history as well as many car and workplace accidents. In fact, research has indicated that driving after going without sleep for 24 hours or less is equivalent to driving under the influence of alcohol. The latter is worse in young drivers under the age of 25 who are often chronically sleep-deprived and therefore more prone to falling asleep at the wheel. Also, driving at night or late afternoon increases the risk of accidents because our biological clocks are genetically programmed to make us sleepy during these hours.

Anxiety and depression
Our internal biological clock is also influenced by bright light and the length of daylight exposure it receives. That is why some people experience bouts of depression during the shorter days and longer nights of winter. Any changes in your sleep pattern, especially loss of sleep, may also cause symptoms of anxiety and depression. Research has shown that up to 50% of people with depression also have some type of sleep problem.  

Monday morning blues
Monday morning blues – that feeling of heaviness and depression that assails us when we have to go back to work – is also closely associated with our biological clock that regulates our cycles of sleep and wakefulness. By staying up later over a weekend and getting up later the following morning we are forcing it to try and adjust to new, unfamiliar cues and to fall behind our usual weekday sleep/wake cycle with the above-mentioned effect.

Foggy brain
Researchers have also found that certain brain activities happen when we are sleeping at our soundest. These brain activities are responsible for transferring learned information to areas of the brain where long-term memories are stored. Lack of sleep may, therefore, have a negative influence on retaining information memorised and vice versa.

Impaired immune system
Stress is a known immune system suppressor and lack of sleep is a stress trigger. Some people argue that sleep may allow the body to conserve energy and other resources needed to fight infections while lack of sleep will do the opposite. It is interesting to note that infectious diseases often force us to take to our beds and makes us sleepy.

Weight gain
Although a good night’s sleep is usually a period of enforced fasting, lack of sleep seems to increase hunger and appetite and consequently body weight. Adding alcohol to the situation will lull you into feeling sleepy but keep you awake later in the night.

Less sex
Overweight, stressed out, depressed, sleep-deprived men and women understandably lack the energy and drive to have sex.

Facing the challenges

Although sleep needs vary, most sleep experts agree that adults need approximately eight hours per night, teenagers nine or more, toddlers (3 to 5 years) 10 to 12 hours and infants at least 16 to18 hours per night.

The following tips will help prevent sleep loss and a sleep debt from building up:

  • Stick to a regular sleep pattern as much as possible, for example go to sleep at the same time every night and get up the same time as usual, even over weekends
  • Keep your bedroom cool, dark and silent. Remember your biological clock responds to external signals such as light (wake up) and darkness (go to sleep)
  • Finish eating at least one to two hours before going to bed, lose the booze and can the coffee. Rather sip some herbal tea such as calming chamomile
  • Keep the TV and any other electromagnetic devices out of the bedroom. Try to de-stress a bit before going to bed; either meditate or do a few mild, relaxation exercises.

Remember, we humans have been genetically engineered to function best when we sleep at night and work during the day!

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