One of the natural functions of us as humans, which has puzzled scientists for thousands of years, is why do we sleep? Sleep is an incredibly important part of our biology, and its function is beginning to be revealed by neuroscientists fundamentally, in the past, there are 3 different consensus regarding why we sleep and its function, these are.
Sleep helps us restore mental energy
: This is the idea that we have to restore our energy back to levels which will enable us to function mentally. Recent discoveries are shown this hypothesis to have some validity, in as much as, there are certain genes within the brain that switch on and off neural pathways, when we are asleep. This idea is nothing new in fact it was quoted by Greek philosopher Aristotle.
- Sleep helps us conserve energy: the idea that we need to recharge our batteries so that we can work the next day. This is doubtful, as there is no real evidence to say that we are saving energy when we are sleeping. In fact, we save about a hundred calories when we are asleep. So there is very little evidence to support this hypothesis.
- Sleep helps mental health: this hypothesis says that we need to sleep to help us process memories, and makes sense of our world as a whole. There is some validity in this hypothesis. As certain areas of the brain are switched on only during sleep. There is an exciting by-product of this brain activity, in that after a good night’s sleep, we are able to think more creatively. Neuroscientists have found that we have a threefold advantage in thinking creatively, about a problem, when compared to broken or no sleep.
Sleep is an incredibly important function for us as human beings, and its importance is only now being recognised. The idea that sleep is for wimps, as Margaret Thatcher once quoted, is now itself, to be scoffed at.
The effects of sleep of overstretched shift workers
In the nineteen fifties the average person got, on average, 8 hours sleep a night. Today, this is now greatly reduced with the average being one half to 2 hours sleep less. The typical teenager needs around 9 hours sleep a night, unfortunately this demographic falls into one of the worst offenders, for lack of sleep, with the average teenager getting around 5 hours a night, that’s 4 hours less sleep than they need.
Shift workers, are on average, the most sleep deprived people, as when they feel tired, after working a night shift their clock body wants them to wake up. Therefore, the quality of sleep they get is generally very poor.
The effects of lack of sleep have been well documented, particularly in the US, where it is well documented that on average hundred thousand people, each year fall asleep that the wheel of their car.
One of the contributing factors in two of the worst accidents in human history, the challenger space shuttle and the nuclear reactor incident at Chernobyl was sleep deprived shift workers, making catastrophic mistakes.
Physical effects of sleep deprivation; how lack of sleep can really affect your health.
From above information we can work out that most people do not get enough sleep. One of the ways that we keep ourselves awake, when we should be sleeping is by using stimulants, the most common being caffeine. Often caffeine is added to with another stimulant nicotine. After staying up all night, it’s then hard to get to sleep because the caffeine in our system is making us stay awake, often people will resort to a sedative the most common being alcohol. This is okay short-term but long-term it can have devastating effects. Unfortunately, alcohol only mimics sleep by sedating the user, it actually harms some of the neuro processing which happens during sleep.
Another factor for loss of sleep is weight gain, if you sleep 5 hours a night, then you have a 50% likelihood that you would become obese. One of the side effects of sleep loss is the increase in the hormone, leptin ghrelin: the hormone that makes you hungry, or increases appetite, this hormone actually seeks out carbohydrates in the form of sugars, so thus increases your likelihood of eating sweet.
Another factor, from lack of sleep, is stress, and with it loss of memory, also suppressed immunity due to your body being stressed.
Another factor for sleeplessness is increase glucose in your blood, after a time you could become glucose intolerant, and thus there is a propensity for diabetes.
There are certainly some studies that show that nightshift workers have an increased cancer risk, due to suppressed immune systems.
Another by-product of sleeplessness is stress on your cardiovascular system, thus increasing your chances of cardiovascular problems.
Overall, poor sleep is bad for you, not only short-term but long-term. What some people don’t realise is it’s not just impaired memory and functioning, but long-term health problems, such as mentioned above.