Monday morning was difficult in my house. “Spring Forward”— in theory —is great. All that extra daylight at the end of the day seems to bring with it a sense of abundance and possibility. However, losing that extra hour of sleep knocked us all for a loop. It got me thinking about why we need our sleep and why losing just one hour can make us feel off our center.
This week is National Sleep Awareness Week, a public health campaign spearheaded by the National Sleep Foundation to highlight the importance of sleep. They use this seasonal time change as an opportunity to spread their message that getting regular, quality sleep is a key component in health and well-being. In fact, along with nutrition, exercise, stress management and relationships, sleep is a foundational pillar of our lifestyle-as-medicine model. But there are some things about sleep you may not know — and these things are BIG.
Big Thing #1- While the brain sleeps, it clears out harmful toxins in a process that may reduce the risk of Alzheimer's and other brain diseases.
A 2013 study funded by the National Institute of Neurological Disorders and Stroke found that during sleep, the flow of cerebrospinal fluid in the brain increases dramatically, washing away harmful waste proteins that build up between brain cells during waking hours.
Scientists conducting this study noticed that during sleep, the system that circulates cerebrospinal fluid through the brain and nervous system was pumping fluid into the brain and removing fluid from the brain in a very rapid pace. (They discovered this by looking at the brains of mice.) The researchers noticed an increased flow was possible in part because when the mice went to sleep, their brain cells actually shrank, making it easier for the fluid to circulate. Upon waking, the brain cells enlarged again, the flow between cells slowed to a trickle and life proceeded as normal.
Big Thing #2: This study may offer the best explanation yet of why animals and people need sleep. Sleep’s brain-cleansing process washes away waste proteins that are toxic to brain cells, which could explain why we don't think clearly after a sleepless night and why a prolonged lack of sleep can actually be life threatening. In fact, if this proves to be true in humans as well (to date, the study has been done on mice, rats and baboons), it could help explain a mysterious association between sleep disorders and brain diseases, including Alzheimer's.
Big Thing #3: According to one of the authors of the study, this brain cleaning takes so much energy that it isn’t possible for the brain to both clean itself and at the same time be aware of its surroundings and necessary functions in the world. It’s only during sleep, when the body can pool its resources, that the energy required for this important work is available.
Just think of sleep as housekeeping for the brain. Actually, for the whole body.
So how much sleep do we really need? The National Sleep Foundation recommends the following:
School-Age Children (6-13): 9-11 hours
Teens (14-18): 8-10 hours
Adults (18-64+): 7-9 hours
A growing body of research is lending more and more support to the vital link between sleep and health. And this new study reinforces the idea that sleep is truly a biological need. Sweet dreams!
*Read the complete study here.