Light entering the eyes is responsible for every aspect of human growth and health. The wrong kind of light can make you ill, perhaps even kill you. The right kind of light can help you well and add years to you life. Light therapy has produced benefits to those suffering from major depression, sadness, chronic fatique, allergies, immune disorders, learning difficulties and neurological problems. Light entering the eyes causes nerve impulses that influence the lower brain and pituitary gland that trigger the release of hormones responsible for every aspect of human growth and health. Light is a nutrient much like food.