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Categories > Mental and Emotional Health > Depression

Just blue? Or could you have seasonal affective disorder?

Suzy lives in Buffalo. Last winter, she gained 20 pounds, performed poorly at work and spent most of her off time asleep. She refused most social invitations and cried a lot. Over the summer, she felt better and wrote the entire episode off as a bout with the blues.

As winter neared again, however, she began to worry because her symptoms seemed to be returning. Fortunately, she followed her best friend’s advice and consulted a doctor, who told her she had SAD—seasonal affective disorder.

SAD affects up to 10 to 20 percent of Americans, most of them women who live in northern areas, where short winter days mean less exposure to sunlight. The cause of this type of depression isn’t known, but researchers believe that the eye’s sensitivity to light plays a role. People with SAD may have retinas that don’t work as they should, making it impossible for their eyes to absorb enough light from short winter days.

A shortage of light entering the eye may cause changes in body chemistry that trigger the symptoms of SAD, which include depression, daytime drowsiness, extreme weight gain, difficulty awakening in the morning and carbohydrate cravings.

SAD shouldn’t be confused with the winter blahs or cabin fever. It’s a psychiatric illness that requires medical attention. SAD is treated with light therapy, which involves exposing the eyes to additional light for anywhere from 30 minutes to two hours a day. The light can come from the sun or from a light box, which provides between five and 20 times the light of an ordinary lamp.

Many people with mild cases of SAD find that spending an hour outside each morning relieves their symptoms. Of course, during extremely cold temperatures or bad weather, it may be wiser to use a light box. Light-box treatment may also be recommended for more severe cases.

Patients spend a half hour to two hours each morning sitting with their faces about 18 inches from the box, which measures about 2 square feet. They can read or eat, as long as they face the light and keep their eyes open.

For many patients, light therapy relieves symptoms within two weeks. However, treatment must continue all winter long or symptoms will return.

Suzy’s story ends happily. Thanks to the light box she purchased on the advice of her physician, her symptoms stopped and she’s free to appreciate what winter has to offer.