The importance of light - beyond vision - has been known in all cultures for millennia. Think of the Sun Gods, Christmas Lights. . . . The scientific research effort, though, is recent. It was inspired by findings that light exposure directly affects hormone levels and can reset the body clock either forward or backward.
Light therapy is a simple, medically recognized, efficient treatment to fight Seasonal Affective Disorder (SAD), the milder winter blues and some sleep disorders.
