People with a family history of SAD are more likely to be at risk. Women are three times more likely to experience SAD than men. And people living in northern climates are also more at risk. Symptoms must also have occurred for at least the previous two years, with no non-seasonal depression episodes. Rosenthal recommends you think about the last couple of Thanksgivings and Christmases and recall how you felt.
People can get treatment right now, and if they respond, they'll be ready next winter.
Lighten up While the exact cause of SAD is not known, people with the disorder can bask in the cheerful news that SAD is generally more easily treated than clinical depression. The standard treatment is light therapy. Researchers are not exactly sure how it works, but one theory is that the lack of sunlight causes the body to produce more melatonin, a hormone that helps regulate seasonal rhythms and sleep. This excess melatonin may in turn cause serotonin deficiencies linked to depression. Exposure to light seems to diminish the effects of this process.