One more reason to get a good night’s sleep
Day 27 / 365
We spend about a third of our lives sleeping. We know that less sleep will leave us feeling murky, whereas a good night’s sleep would make us feel refreshed. How exactly that happens, is still an open question for scientists. In this Ted talk Jeff Iliff proposes a theory as to how our brains go through a waste clearance phase when we sleep.
The build-up of waste in the brain
Every organ in our body requires nutrients to function, and our blood handles supplying these nutrients along with oxygen to all parts of our body. The brain especially requires a lot of this, as it responsible for 25% of all of our energy consumption.
As our organs use up these nutrients to do their jobs, they generate waste in the process. The collection of this waste is carried out by another system of vessels known as the lymphatic system. These vessels are the garbage collectors of our body. They take the waste from the cells and carry it over to the blood to get disposed of.
Here’s where things get interesting. The brain consumes so much energy and produces a lot of waste. But there are no lymphatic vessels in the brain!
How the brain cleans itself while we sleep
The brain can’t clear out waste the usual way as other organs do. Instead, it uses something called Cerebrospinal Fluid (CSF) which is a clear fluid present in the brain and spinal cord. CSF can flow through the brain cells, collecting waste and passing it on to the bloodstream. The important point is that this happens largely when we are sleeping.
When we sleep, our brains shift into cleaning mode. The brain cells actually shrink a little, allowing CSF to flow through easily and collect the waste from between the cells.
Could you imagine not cleaning your kitchen properly for a month? It would quickly become unlivable. And that’s kind of what we do to our brains if we don’t sleep well. The built up of such waste in the brains have been associated with mental conditions, including Alzheimer's.
How much sleep is necessary for you? the answer varies from person to person, but a good estimate is 7–8 hours. So find out what works for you and make sure you give your brains enough time to clean up!
This story is part of my 365 Day Project for 2019. Read about it here
Yesterday’s blog — The re-discovery of Arthashastra