Melatonin
Gwern comes close to suggesting filtering blue light, but I will repeat a previous post. I've tried melatonin, but it is no substitute for for filtering blue light in my experience, and it tends to induce horrific, apocalyptic nightmares (granted, a night dreaming of EAS Emergency Action Notifications is better than no sleep at all).I used to be an owl for years--decades. A regular 9-5 schedule seemed out of reach. All previous attempts quickly led to backsliding and accusations of moral failure. However, I found that an involuntary physiological response to artificial light in the range 460-484nm was involved.This May I changed my environment by filtering out blue light after 8PM, turning off white lamps and turing on amber compact fluorescents. I'm asleep ~ 10PM and up usually ~ 5AM. This is now my regular schedule. It would have been inconceivable for me six months ago.I use the following:1. Inexpensive Uvex amber goggles from Amazon: http://www.amazon.com/Uvex-S0360X-Ultra-spec-SCT-Orange-Anti... Wear them at least an hour or two before bedtime. I also have the considerably more expensive glasses from lowbluelights.com. In my experience, the inexpensive goggles work just as well, although the more expensive glasses filter more blue light.2. I replaced most of the white compact fluorescent lights in my apartment with amber compact fluorescent lights https://www.lowbluelights.com/index.asp3. And I use a sunrise simulator alarm clock. http://www.amazon.com/Philips-HF3520-Wake-Up-Colored-Simulat...
Sometimes I forget to set the clock--now I don't seem to need it.Not to mention f.lux (pardon the paralipsis), though again, in my experience, filtering is necessary.Concerning the scientific basis for the claim that blue light in the range 460-484nm suppresses melatonin production, here is one reference: http://en.wikipedia.org/wiki/Photosensitive_ganglion_cellMoral: Nagging and moralizing was both uninformative and ineffective. Science and engineering was both informative and effective.