the region of the country you live in can impact your risk of suffering from depression—at least from november through april.

　　that's because those living in the northern part of the country are more at risk of suffering from seasonal affective disorder, a form of clinical depression brought on in the winter months by the shortening of the days and the later sunrise.“in the united states, sad is about five times more prevalent in the northern tier of states than in the far south,” says dr. michael terman, director of the center for light treatment and biological rhythms at the columbia university medical center.but sad is just the tip of the iceberg, explains terman. “less severe ‘winter doldrums' occur at least three times more frequently than winter depression. even more people experience one or more symptoms of winter depression—such as overeating or oversleeping—even though their mood stays under control.”

　　whatever the degree of impairment, symptoms tend to resolve in the spring. “certainly there is no lack of happiness up north for the six months from may to october,” terman says.