A LOT of caffeine through the day seems to have had an impact on my sleep. I tried to get lots of sleep but dragging oneself off to bed before 2200hrs is difficult. I only have one coffee a day now (if at all), and moderate my tea drinking (no more than four cups a day, and seldom after 1600hrs). The big change though, has been with sleep.
I work hard at getting to bed shortly after 2100hrs to read and then meditate. I am strongly aware of the importance of sleep for several years and divided sleep in particular. Sleep is doctor, counsellor, psychiatrist, physiotherapist, massively anabolic, and generally restorative at every level. I hit the gym hard three times a week and know that this must be mirrored in terms of quality and quantity of sleep.
All this stuff was thrown back in to perspective again today by the re-trending today of this story on the BBC site from 2012, The Myth of the Eight Hour Sleep.
I typically awaken at 0230hrs each morning and will be awake for 30-60 minutes, but then sleep pretty solidly until around 0600 - 0630hrs. As a coarse indicator of sleep hygiene, I'd say that this is spot on!