When I was younger, I could sleep for hours non stop, undisturbed sleep easily for at least 10-13 hours a go. I also used to have Sunday bath night (yeah, I'm that cool) I used to light candles, add oils and bubbles and settle in for an hour or two for total relaxation. I used to stay up for 2 days in a row and eat whatever I liked.
Nowadays, I find it hard to sleep for more than 8 hours max, I try but it never works, unless I'm ill. I run baths, settle in for a good hours reading and after 20 minutes I get bored and have to get out of the bath. As for staying up, I like regualrity in my life now and as for eating, I have to eat certain sized portions or I gain more weight then I'd like and I have to make sure I don't eat as many sweet foods.
It sucks being older in many ways but it is also so cool....I'm so more aware of who I am and what I like, am having more fun and don't bother hanging around people who bore me now a days, etc.