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Seasonal Affective Disorder

Feeling down? Is this bluesy feeling something that you experience every winter? Like many Americans, you may be suffering from Seasonal Affective Disorder, appropriately known as SAD.

Seasonal affective disorder (seasonal depression) is a mood disorder that happens every year at the same time, usually in winter. Some people with SAD experience very mild symptoms and feel “out of sorts” or irritable. Others have debilitating symptoms that interfere with relationships and productivity.

Criteria to diagnose SAD

  • There is a regular relationship between the onset of depressive episodes and the time of year.
  • This is a repeating pattern for at least the past two years.
  • The cause of the depression is not related to an obvious seasonal psychosocial stressor, such as being unemployed every winter.
  • Depression disappears in the spring.
  • No non-seasonal episodes of depression have occurred during the same time period.

Source: Diagnostic and Statistical Manual of Mental Disorders (DSM IV-R) American Psychiatric Association, 2000.

What causes SAD?

Although the exact cause is unknown, researchers believe that changes in the amount of daily sunlight cause changes in the body’s internal biological clock, known as our circadian rhythm, and in turn, mood altering brain chemicals.

Circadian rhythm is a 24-hour cycle that affects our eating and sleeping patterns, brain wave activity, hormone production, and other biological activities. In susceptible people, less daily sunlight and the seasonal changes in circadian rhythm can bring on depression and negative thinking.

Experts also believe that reduced sunlight during fall and winter leads to lower production levels of the “feel good” chemical serotonin in the brain. When you are “a quart low in serotonin,” you can feel tired, depressed, and crave carbohydrates.

How can I recognize SAD in myself or a family member?

Here’s a quick checklist to help you determine if you or your loved one should talk to a mental health professional or your doctor. Answer the following questions with a check mark if it is typically true for you.

In the darker months, do you:

  • feel more tired (have a lower energy level)?
  • become irritable?
  • have trouble waking up in the morning?
  • require more sleep?
  • crave carbohydrates more than in the spring and summer?
  • typically gain weight?
  • visit your physician more often than at other times of the year?
  • drink more alcohol when the days are shorter?
  • have a lowered sex drive?
  • become socially withdrawn?

If several of the points above apply to you, it is important for you to see your doctor so you can feel better. Remember, the key to whether this is SAD or another kind of depression is that these problems show up for you during the winter months and disappear in the spring.


Author: Jane Riffe, former WVU Extension Specialist in Family & Human Development