Seasonal Affective Disorder (aka SAD) is a form of major depression that appears late in the year, when the days get shorter and the temperatures get colder. Recent reports show that episodes of SAD last about four months and up to 35 percent of sufferers require hospital care at some point. People with SAD also tend to eat more junk food and food rich in carbohydrates. Although the cause of seasonal affective disorder is unknown, antidepressants and behavioral therapy can help treat it. Cleveland Clinic psychologist Dr. Michael McKee offers suggestions on how people with SAD can also spend more time in the light and getting active, including light therapy.