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Written by Alicia Cassels, OneOp Program Development Specialist, Auburn University

 Season Affective Disorder

What is Seasonal Affective Disorder?

Seasonal affective disorder is a form of depression which is also referred to as SAD. Although a small portion of individuals experience SAD in the spring and summer, SAD tends to be experienced during the fall and winter months by the vast majority of people. It is important to recognize the potentially serious symptoms associated with SAD, a condition that may require medical treatment.

What are the symptoms of SAD?

According to the American Psychiatric Associationsymptoms of SAD can vary from mild to severe and may include:

  • Feeling of sadness or depressed mood
  • Marked loss of interest or pleasure in activities once enjoyed
  • Changes in appetite; usually eating more, craving carbohydrates
  • Change in sleep; usually sleeping too much
  • Loss of energy or increased fatigue despite increased sleep hours
  • Increase in restless activity (e.g., hand-wringing or pacing) or slowed movements and speech
  • Feeling worthless or guilty
  • Trouble concentrating or making decisions
  • Thoughts of death or suicide or attempts at suicide
  • SAD may begin at any age, but it typically starts when a person is between ages 18 and 30

What Causes SAD?

According to the National Institutes of Mental Health, while the exact causes of SAD are unknown, researchers have identified some biological clues:

“People with SAD may have trouble regulating one of the key neurotransmitters involved in mood, serotonin. One study found that people with SAD have 5 percent more serotonin transporter protein in winter months than summer months. Higher serotonin transporter protein leaves less serotonin available at the synapse because the function of the transporter is to recycle neurotransmitter back into the pre-synaptic neuron.

People with SAD may overproduce the hormone melatonin. Darkness increases production of melatonin, which regulates sleep. As winter days become shorter, melatonin production increases, leaving people with SAD to feel sleepier and more lethargic, often with delayed circadian rhythms.

People with SAD also may produce less Vitamin D. Vitamin D is believed to play a role in serotonin activity. Vitamin D insufficiency may be associated with clinically significant depression symptoms.”

What are the Risk Factors for SAD?

According to the Mayo Clinic:

  • SAD is diagnosed more often in women than in men.
  • SAD is diagnosed more frequently in younger adults than in older adults.
  • People with SAD may be more likely to have blood relatives with SAD or another form of depression.
  • Symptoms of depression may worsen seasonally if you have depression or bi-polar disorder.
  • SAD appears to be more common among people who live far north or south of the equator. This may be due to decreased sunlight during the winter and longer days during the summer months.

How is SAD treated?

Your treatment provider will work with you to develop a specific treatment plan based on a number of available treatment options. Treatment interventions for SAD may include Bright Light Therapy (BLT) or phototherapy, which works to replace sunshine using artificial light. BLT typically involves sitting in front of a light box which emits full spectrum light similar to sunlight, while filtering out ultraviolet rays. Additional treatment interventions for SAD include Vitamin D, counseling, and/or antidepressant medication (Melrose, 2015).

What should you do if you think you may be experiencing SAD?

SAD is a form of depression. It is important to seek the help of a trained medical professional if you believe that you are experiencing symptoms of SAD. A medical provider or mental health professional can develop a diagnosis and work with you to identify appropriate treatment options. The National Institute of Mental Health offers additional information and resources on SAD and depression. SAD can present very serious symptoms. If you are currently experiencing serious symptoms, the American Psychiatric Association offers this recommendation:

“If you feel the depression is severe or if you are experiencing suicidal thoughts, consult a doctor immediately or seek help at the closest emergency room.”

National Suicide Prevention Lifeline  800-273-TALK (8255).

References and Resources:

Melrose S. (2015). Seasonal Affective Disorder: An Overview of Assessment and Treatment Approaches. Depression research and treatment2015, 178564.

NIMH » Seasonal Affective Disorder

Seasonal Affective Disorder (SAD)

Seasonal Affective disorder (SAD) – Symptoms and Causes