It seems the eggs improve the sleep, because after poor sleep, eggs the following day seem to have an effect on breaking the poor-sleep doom loop (which is: poor sleep elevates cortisol, adrenaline, heart rate, junk-food cravings, and the need for caffeine--all of which contribute to another night of bad sleep). Not sure if it's the choline, which eggs have a lot of, or the egg-generated satiety that helps prevent eating too much. I think it may be the choline because when I'm otherwise eating high-choline foods such as red meat, my sleep is also better.