PITTSBURGH AIR RESERVE STATION, Pa. -- Some people suffer from symptoms of depression during the winter months, with symptoms subsiding during the spring and summer months. This may be a sign of Seasonal Affective Disorder (SAD).
SAD is a mood disorder associated with depression episodes and related to seasonal variations of light. SAD was first noted before 1845, but was not officially named until the 1980’s. Sunlight has affected the seasonal activities of animals such as reproductive cycles and hibernation, and SAD may be an effect of the seasonal light variation in humans.
As the seasons change, a shift occurs in our “biological internal clocks” or circadian rhythm, partly due to these changes in sunlight patterns. This can cause our biological clocks to be out of “step” with our daily schedules. The most difficult months for SAD sufferers are January and February, and younger persons and women are at higher risk.
Symptoms
- regularly occurring symptoms of depression such as excessive eating and sleeping and weight gain during the fall or winter months.
- full remission from depression occurs in the spring and summer months.
- symptoms have occurred in the past two years, with no non-seasonal depression episodes.
- seasonal episodes substantially outnumber non-seasonal episodes.
- cravings for sugary and/or starchy foods.
Possible Cause of This Disorder
Melatonin, a sleep related hormone secreted by the pineal gland in the brain, has been linked to SAD. This hormone, which may cause symptoms of depression, is produced at increased levels in the dark. Therefore, when the days are shorter and darker, the production of this hormone increases.
Treatments
Phototherapy or bright light therapy has been shown to suppress the brain’s secretion of melatonin. Although there have been no research findings to definitely link this therapy with an antidepressant effect, many people respond to this treatment. The device most often used is a bank of white fluorescent lights on a metal reflector and shield with a plastic screen. For mild symptoms, spending time outdoors during the day or arranging homes and workplaces to receive more sunlight may be helpful. One study found that an hour’s walk in the winter sunlight was as effective as 2 ½ hours under bright artificial light.
If phototherapy doesn’t work, an antidepressant drug may prove effective in reducing or eliminating SAD symptoms, but there are unwanted side effects to consider. Discuss your symptoms thoroughly with your family doctor and/or mental health provider.
Resources
For more information, contact your local mental health center or contact the following:
Society for Light Treatment and Biological Rhythm
P.O. Box 591687
174 Cook Street
San Francisco, CA 94159
http://www.websciences.org
Mental Health Resource Center
800/969 National Mental Health Alliance (NMHA)
TTY Line 1(800) 433-5959
http://www.nmha.org
National Mental Health Association
2001 N. Beauregard Street 12th Floor
Alexandria, VA 22311
(703) 684-7722