According to the National Institute of Mental Health, about 8% of adult women in the U.S. will have a depressive episode this year. You probably know someone who's dealt with it (or maybe that person is you). But there's still so much we don't know about the disorder.
For instance, depression shows up differently in various people, and researchers are working on learning why that might happen. Some people may feel physical symptoms, like chronic pain. Others may only feel moderately depressed, but for longer periods of time (dysthymia). Sometimes depression is treated after a few months and never comes back. Yet other times, people have recurring episodes of major depression, or episodes that aren't helped by even our most advanced treatments.