In an age of round-the-clock news and information it can be tempting to view the need for sleep as an inconvenience. But “need” is indeed the imperative here. Have you ever considered why lack of sleep can kill, is used as a form of torture, is linked with early death from any disease, increases the risk of developing diabetes, obesity, mental illness, Alzheimer’s and cancer? Perhaps you know that sleep is important but haven’t considered why. It would also be easy to think that as we lie and sleep our brain somehow turns down it activity and function but to the contrary, the brain uses as much fuel as we sleep as when we are awake. An astounding fact in itself.
It is has been know for a long time that sleep is essential for memory consolidation and recharging cells, but now an even more incredible discovery has been made. A new imaging technique has shown that during sleep the brain cells of mice (which serve as a good models for human brains) shrink by up to 60%, leaving much more space for the brain’s plumbing system, or more technically the glymphatic system, to drain away the brain’s metabolic waste products, sweeping it into the blood vessels and eventually through the liver.
This brain-waste removal service operates 10 times more effectively during sleep. When you rise unrefreshed after a night of broken sleep and feel hungover your brain is quite literally unrefreshed.
The fingerprint of design runs through the night and presses the reset button. In light of this newly discovered nocturnal brain detox, disorders such as depression, anxiety and Alzheimer’s start to become more easily understood as a physical disorder and it is possible to see how sleep could have a premium role in the management and prevention of these disorders.