Rings personally true for me. I can do fine on five hours for quite a while although it's somewhat tiring, while six is usually enough for me generally. Same fo

Rings personally true for me. I can do fine on five hours for quite a while although it's somewhat tiring, while six is usually enough for me generally. Same for my father who always has slept relatively little. What I'd really like to see is more research into individual variance. I felt quite guilty about my sleep habits because people kept going on about eight hours. A few years ago there was a book about this that made the tours on every news show until it was torn apart for making half of its content up.