The question if a person really needs sleep is constantly asked. Just like hunger, thirst and sexual desire, the urge to sleep is a physiological drive. Exactly what spending a third of our lives unconscious gets us, however, has long mystified scientists.

Research over the past 20 years has finally begun to provide at least a partial explanation for why we must sleep. The clearest finding is that sleep does not serve just a single purpose. Instead it appears to be needed for the optimal functioning of a multitude of biological processes – from the inner workings of the immune system to proper hormonal balance, to emotional and psychiatric health, to learning and memory, to the clearance of toxins from the brain. At the same time, none of these functions fails completely in the abscence of sleep. In general, sleep seems to enhance the performance of these systems instead of being absolutely necessary, as the Reader Digest points out. And yet anyony who lives for months without sleep will die.

Even this imperfect understanding has taken decades to develop. By the end of the 20th century researchers had replaced ancient notions about sleep – that it was caused by blood retreating from the surface of the skin or by the buildup of warm vapors from the somach – with detailed measurements of brain-wave activity, breathing patterns, and daily oscillations in the amount of hormones and other molecules in the blood. More recently, investigators have begun identifying the exact aspects of sleep that are important for each of its benefits. Ironically, though, the more researchers uncover about the unconditional necessity of a good night‘s sleep for the proper functioning of mind and body, the less time 21st-century citizens spend in the soothing arms of Morpheus, the greek god of dreams.

Now the clearest evidence of absolute need for sleep comes from a study published in 1989. The researchers found out the all the rats who didn‘t sleep died within a month. All they had to do to achieve this fatal result was to prevent the animals from entering the stage of sleep characterized by rapid eye movement (REM). But over 30 years later researchers still cannot explain why the rats died. Imagine if you would not be able to sleep for a couple of months. You would definitely go crazy. Your body and your mind would feel like numb and you would have some serious health issues. The strain on your body would lead to some serious damage that would affect your body from the brain to all the way down to your back.

Due to the research their was still no reason found why those animaly died but a series of experiments that were done later served to eliminate possible causess. So it is not caused by, for example, increased stress, excessive energy consumption, or failure of the body‘s internal heart regulators or the immune system.

Death by sleep deprivation is not only unique to rats. Fatal familial insomnia, first described about 30 years ago, is, as the name suggests a heritable human disorder that leads first to unremitting insomnia and thence to death. Now it is still not unclear what exactly causes the death when we stop sleeping. However we know for a fact that sleep is important for your body and mind