Due to some medical problems involving endocrinology, I imagine my body being somewhat more sensitive to hormonal/nutrient changes than the norm. Nothing insurmountable - apart from my chronic medication, the normal rules of eating healthily, exercising, and getting enough sleep seem to do the trick well enough to see me through the normal day-to-day.
A year or two ago I started in a job that required (tele or physical) presence for releases every second week (a lot of people where involved each time, it mostly involved waiting for everyone to do what they do, doing some checks in your own area of responsibility when the time came around). This normally was scheduled to start at 22:00 or 00:00, often it only finished around 06:00 or 07:00. (This was after working a normal 8-5 workday...)
Of course, everyone was given time off for the time spent on releases. But getting home at (say) 7, trying to sleep was nearly impossible for me. In my case I'd sleep maybe an hour or two, then wake up tired and grumpy, and because there was nothing else to do, eventually go back to work to put in a handful of (sluggish) hours. I did feel that I only got back into a fairly normal routine, waking up refreshed and ready, after about a week. Rinse and repeat. Apart from an inability to concentrate sufficiently at work, it also left me listless and tired. My social life suffered, as well as "reading up" I would normally do on subject matter in the evenings to keep up with developments in my field. Not good for work performance, or career in general....
Yeah, imagine a multi-million company thinking that such practices are good w.r.t. their mission critical systems.... (You can imagine what other "innovations" such an organisation can dream up.) I'm glad I'm out of there, money or not.
(I don't envy parents of small babies in this regard, but that is another matter for now.)
While sleep researchers seem to be clear that they still know very little about their subject, the basics of the light/dark cycle (including "blue" and "yellow" light) and its influence on hormones (melatonin, serotonin, ...) seem to be in place. These hormones can have a profound effect on brain function and other health issues. It's a no-brainer, really.
I'm currently trying to uphold a routine (including weekends and holidays) of bedtime around 21:00 or 22:00 at the latest, which allows me to wake up naturally (no alarms) around sunrise. Routine does not go together well with exceptions, which is a bit sucky when you are doing a little evening coding and get into the "flow" and just want to finish one last thing... Might also interfere with some socialising. But on the whole, a healthy sleep routine is benefiting me at least as much as all the healthy eating and exercising combined.