Only REM stage actually cleanses the brain from toxins. If you don’t or barely reach it, you will wake up more tired than before you slept.
Yeah, I agree entirely. I don't sleep worth shit no matter what I do and I don't get very much REM. When I do I feel way better and its easier to do basically everything.
REM actually kind of scares me. I feel like a bitch admitting that, but my dreams are almost always nightmares. Sleep without them is preferable. Guess I'm screwed either way.