What you do with your body throughout the day influences how well you sleep at night. If you put a lot of junk into your body during the day, don't expect the resulting neurochemicals to become nicer at night.
Besides eating whole foods and moving your body, getting enough sleep is the most important thing you can do for your health. Sleep deprivation makes you fat and leads to depression, diabetes and pain.
We have a greater chance to achieve our highest potential -- including getting a fantastic night's sleep -- when our "chi," or human life force energy, is in balance and harmony with the energies of the earth.