sleep

Do we need 8 hours of sleep every day?  I sleep less and less as I get older.  I wake up early and want to get going on the day.  It doesn't feel like it's for stressful reasons, but for happy reasons, enjoying life.  I go to bed too late because I work in the evenings and don't wind down, plus I want to read in bed before going to sleep.  I think I only sleep about 6-7 hours a day.   I have catch-up days where I sleep almost 8 hours.   Is that bad?  I feel okay.  I used to sleep much more.  I wonder if I need less sleep since I am more healthy than I used to be and my body doesn't have to work as hard to remove toxins.