By Emma Johnson, LMFTC
Seasonal Affective Disorder (SAD) is a type of depression and in the Diagnostic Manual of Mental Disorders (DSM-5) identified as Major Depressive Disorder (MDD) with Seasonal Pattern. SAD is different than MDD because of the onset and remission of the major depressive episodes occurring at specific and recurrent times each year.

Oftentimes, SAD is referred to as seasonal depression, winter depression, or the winter blues because of when people experience symptoms. Typically, people with SAD experience symptoms in the Fall and Winter months when there is less sunshine, and these symptoms often go away in the spring and summer months. Due to shorter daylight hours and less sunshine in the Fall and Winter, people experience a shift in their biological clock and circadian rhythm creating a biochemical imbalance.
Diagnostic Criterion:
- Major depressive episodes are experienced at characteristic times during the year (typically Fall and Winter).
- The seasonal depressive episodes must be present for at least a two-year period without the presence of any non-seasonal episodes during this timeframe.
- The presence of seasonal depressive episodes must outnumber any nonseasonal depressive episodes over the individual’s lifespan.
- Seasonal depressive episodes cannot be explained by any other situational factors such as seasonal unemployment.
Population:
SAD can develop at age any age, however, most commonly begins around age 18-30.
SAD impacts both men and women, however, is more common among women.
Common Symptoms:
- Feeling sad
- Feeling worthless
- Loss or interest in things previously enjoyed
- Changes in appetite (primarily increased appetite and cravings for carbohydrates)
- Changes in sleep (primarily increased need/desire for sleep)
- Loss of energy/increased fatigue
- Weight gain
- Difficulty concentrating
- Thoughts of suicide
Treatment:
Symptoms will typically improve on their own as the season’s change, however, this process can be accelerated through the use of certain treatments including:
- Light Therapy/Exposure
- Talk Therapy
- Antidepressants
Light Therapy (also called phototherapy) is the practice of sitting in front of a light therapy box that emits a bright light while simultaneously filtering out harmful UV rays for approximately 20-minutes a day. During the winter months and when there are minimal daylight hours, this process is recommended to be done first thing in the morning. The emitted light mimics natural light and has been shown to help alter brain chemicals linked to mood.



Within one to two weeks, individuals with SAD begin to see symptom improvement, however, to maintain this, treatment is oftentimes continued throughout the entirety of the winter months. Light therapy will oftentimes restart in the Fall months to prevent the onset of symptoms. Increasing your exposure to direct sunlight can also improve some of the above symptoms and can be accomplished by spending more time outside or rearranging your home or office to allow for more window exposure.
Talk Therapy allows for a space to figure out how to eliminate or maintain some of the symptoms experienced. Cognitive Behavioral Therapy (CBT) and the process of practicing new skills to alter negative thinking and behavioral patterns has proven to be particularly helpful in treating SAD.
Antidepressants prescribed for SAD typically fall into the selective serotonin reuptake inhibitors (SSRIs) category.
Outside Sources:
DSM 5: Diagnostic and Statistical Manual of Mental Disorders (2013)
https://psychiatry.org/patients-families/seasonal-affective-disorder