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Seasonal Affective Disorder

Seasonal Affective Disorder

John A. Invernizzi, Ph.D.
    © 2016
The Difference between Non-Seasonal Depression and SAD
Treatment for SAD
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Do you feel tired, moody, and depressed? Are you putting on weight and sleeping more than you normally do? Maybe you are experiencing SAD.
     Seasonal affective disorder (SAD) is mood disorder (a type of depression) that occurs at a certain time of the year, usually in the winter.  Your symptoms may start in the fall and could continue into the winter months, taking away your vigor and making you feel temperamental. 

What is SAD?

      Experts are not sure what causes SAD, but they suggest a lack of sunlight may be responsible.  An increase of symptoms in the fall and winter months as the daylight hours shorten (in the temperate and polar regions) seems to support this theory. 

     Another theory suggests that SAD symptoms might reflect innate, primal winter survival needs.  As humans evolved, limited winter food and reduced daylight hours promoted calorie ingestion and periods of sleep and inactivity.

     There are other theories of why SAD occurs that include biological, environmental, and genetic variables.  Some suggest a combination of factors.

          Fall and winter holidays--Effects on SAD Susceptible People 

What causes SAD?

     SAD symptoms occur around the same time every year.  If the symptoms go away after the season is over (two years in a row), you might have SAD.

     Some SAD symptoms include fatigue, depression, not sleeping properly, and not thinking clearly.  These are also symptoms of some other disorders or conditions (e.g., hypothyroidism), so a diagnosis can be complex.  In addition, there are different types of depression other than SAD.

     SAD can mimic or be comorbid
(when two disorders or illnesses occur simultaneously in the same person) with other conditions, disorders or natural stages of life, e.g., menopause.  SAD occurs more often with women compared to men and could be familial.