Humans need sleep. Everybody knows that without it we get really cranky, we forget things, get easily stressed and a bit loopy. We are at greater risk of heart disease, cancer, diabetes, colds and flu’s and we may gain weight. Yes! The lack of sleep may make us fat. If all the other risk factors are not enough, that should be.
We are also at greater risk of dementia and depression and without enough sleep we may then just die. Unfortunately, science has been a little iffy, a tad unsure about why we need to sleep. Though we understood the negative effects associated with lack of sleep, no one really knew why those things happened.
Now, we’re finally getting some insight into what sleep does for our bodies. For the first time ever, scientists at the University of Rochester USA have found one of the reasons our brain needs sleep to survive. Turns out, when we sleep our brain takes that time to clean out the build-up of brain junk we accumulate during our waking hours. It’s a bit like deleting junk mails and unwanted files from your hard drive and doing a defrag! Sleep is pretty much necessary for our body’s mental street-cleaners to come out and do their work.
When cells do their daily cell-type work, they produce waste product. The rest of the body has this waste cleared out by the lymphatic system our bodies drainage system, but the brain is disconnected from that, so it needs another way to wipe out the waste. The brain has its own rubbish and garbage collection service, carried on the waves of cerebrospinal fluid, who surf the leftovers straight down to your liver for elimination. Wow how good is that! As it turns out, the brain’s garbage collection service moves twice as fast when you’re sleeping, because your neurons shrink by half, making the fluid channels wider. It’s a bit like saying there is less traffic on the roads at night.
This study shows that the brain has different functional states when asleep and when awake. In fact, the restorative nature of sleep appears to be the result of the active clearance of the by-products of neural activity that accumulate during wakefulness. On top of all this the maintenance crews come in and attend to repairs and the immune system has a reboot as well as enhanced mineral absorption. It’s enough to make you sleepy. So get lots of rest, or else your brain’s spinal-fluid surfing street cleaners can’t get their gig done right.
Dr Phil Sheldon