Sleep is very important in all sorts of ways but Professor Walker was throwing everything at the wall in an effort to convince the reader to get better sleep at times. One chapter talking about how people who get less sleep will naturally want to eat more. Another chapter telling how rats with given constant diets and restricted sleep eventually starve to death. I do trust all his citations to be accurate but I'm also sure that if there was some way in which less sleep was good for you he wouldn't mention it.

But it was a very valuable book in terms of explaining just what sleep does for you.

Sometimes I wonder if Mr. Walker is paying people at HN to talk about his book :). Comes up more often than I'd expect.

it's good for you as in it will scare the shit out of you and make you pay attention to your sleep. the examples can be a little exaggerated and one has to wonder how anyone that does not get enough sleep is still alive - but yeah. if you haven't already, read the book