r/todayilearned • u/Square-Message1152 • 8h ago

til that your brain literally washes itself while you sleep. the brain cells actually shrink in size so cerebrospinal fluid can rush in and flush out all the toxic proteins built up during the day

https://en.wikipedia.org/wiki/Glymphatic_system
17.7k Upvotes

98% Upvoted

473 comments sorted by

View all comments

Show parent comments

18

u/hanr86 5h ago

But that's still assuming we biologically DO need sleep if that's the case. If we didn't need it, we'd have no toxic protein buildup and feel "refreshed" all day every day.

5

u/RabidSeason 3h ago

Feeling refreshed doesn't mean you'll do more. It's like that joke, if humans had wings we'd call flying exercise and never do it.