How much sleep is enough? Can you ever catch up on lost sleep? And is there such a thing as too much sleep?
In short, 7 - 8 hours per night, yes but long term lack of sleep may cause lasting effects, and yes.
I know, I really just blew the whole thing there but I doubt you're reading this before you watched the video anyway.
BONUS: 5 Dangerous Things You Should Let Your Children Do