Melatonin is naturally occurring in humans, however the melatonin production reduces the older people get. Alas taking melatonin can have two effects. Increasing the level of melatonin in the body and rejuvenating the melatoning production or rather giving it a boost.
Some years ago I was out like a snowman after flying east west cargo with pick up around 1am for every flight from base and with few or no day flights in months. My sleeping patterns went to a mess. I could not sleep for more than a few hours regardless how tired I was. I took a few melatonin tablets when I returned back to base and henceforth slept extremely well. But I only took the melatonin two days in a row not before or since that, 2006 it seems it was but looks like I am up for another doseage soon.
I tend to agree with most of the tricks here. Good food, physical activity,cat naps etc all work for me. Interesting thread to say the least. Thanks for contributing.