Seasonal affective disorder (SAD) is a mood disorder subset in which people who have normal mental health throughout most of the year exhibit depressive symptoms at the same time each year, most commonly in winter. Common symptoms include sleeping too much, having little to no energy, and overeating. The condition in the summer can include heightened anxiety.

In the Diagnostic and Statistical Manual of Mental Disorders DSM-IV and DSM-5, its status was changed. It is no longer classified as a unique mood disorder but is now a specifier, called "with seasonal pattern", for recurrent major depressive disorder that occurs at a specific time of the year and fully remits otherwise.
Although experts were initially skeptical, this condition is now recognized as a common disorder.

SAD in the United States affects from 1.4% in Florida to 9.9% in Alaska. SAD was formally described and named in 1984 by Norman E. Rosenthal and colleagues at the National Institute of Mental Health.

Icons made by Flat Icons from www.flaticon.com

This guide is for informational purposes only. Please always seek advise from your health authorities and professional.