Is 8h sleep from 22:00 to 6:00 qualitatively equivalent to 8h sleep from 00:00 to 8:00?
I'm not saying this to be a buzz kill, I really wish it wasn't true. Anecdotally, I used to keep very, very late hours and sleep a lot of the day - and I did this for years. I thought I was fine. Once I established a normal day/night cycle (kids and wife do that to you), I realized that I had been grumpy most of the time and not particularly happy. Soon after establishing a more normal rhythm, I also lost a considerable amount of weight (about 15lbs).