Light therapy for sad is one of the means through which SAD can be treated. SAD is an acronym for seasonal effective disorder. It is a disorder that occurs during the fall and winter season when there is reduced sunlight. There are certain symptoms that are associated with this disorder. Some of the symptoms of the SAD are mood disorder, loss of pleasure in normal activities, inability to do some work and the likes. SAD can occur to any person though at different degree. Some people may not also experience it.