Seasonal Affective Disorder (SAD)

September 2024

-Gaby Von Vajna

As the cooler seasons are quickly approaching, some may start to experience symptoms of seasonal affective disorder or seasonal depression (SAD). SAD is a mood disorder recognized as a subtype of major depressive disorder and bipolar disorder. SAD is categorized as recurrent depressive symptoms during the changing seasons (Munir, 2024). Typically, the depressive symptoms show up during the late fall and winter months when there is less sunlight and are typically improved by springtime. However, seasonal depression can also occur for some during the summertime. 

Around 10 million or 5% of adults in the U.S. experience seasonal depression (Torres, 2024). The effects of SAD typically affect more women than men, younger adults, and those who live further from the equator, where there are fewer daylight hours in the winter. The underlying causes of SAD are unknown, however there are several hypotheses presented. These include genetic factors and dysregulation of neurotransmitters such as serotonin, which is responsible for balancing mood. As sunlight diminishes during the cooler months, so do serotonin levels which may trigger depression. Additionally, the changing seasons may affect one’s melatonin production, which plays a role in sleep and mood. Finally, the decrease in sunlight may lead to disturbances in the circadian rhythm or our ‘internal clock’ which leads to feelings of depression. 

Some of the symptoms of winter SAD include; sadness, irritability, social withdrawal, weight gain due to overeating, low energy and sleepiness, decreased interest in enjoyable activities, difficulty concentrating, hypersomnia, and carbohydrate cravings. Treatment of winter SAD include bright light therapy, psychotherapy, antidepressant medication, and taking Vitamin D supplements. It may be helpful to spend time outdoors and get more exposure to natural sunlight, get active, engage in enjoyable activities, and rely on your support system.

References & Further Reading: 

John Hopkins Medicine. (2024). Seasonal affective disorder. Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/conditions-and-diseases/seasonal-affective-disorder

Mayo Clinic. (2021, December). Seasonal affective disorder (SAD). Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/seasonal-affective-disorder/symptoms-causes/syc-20364651 

Melrose, S. (2015). Seasonal affective disorder: An overview of assessment and treatment approaches. Depression Research and Treatment, 2015, 1–6. https://doi.org/10.1155/2015/178564 

Munir, S. (2024, April 20). Seasonal affective disorder. StatPearls [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK568745/#:~:text=The%20DSM%2D5%2DTR%20specifies,disorder%20during%20a%20particular%20season. 

Torres, F. (2024, March). Seasonal affective disorder (SAD). Psychiatry.org - Seasonal Affective Disorder (SAD). https://www.psychiatry.org/patients-families/seasonal-affective-disorder#:~:text=About%205%25%20of%20adults%20in,about%2040%25%20of%20the%20year. 

        Wirz-Justice, A., Ajdacic, V., Rössler, W., Steinhausen, H.-C., & Angst, J. (2018). Prevalence of seasonal depression in a prospective cohort study.          European Archives of Psychiatry and Clinical Neuroscience, 269(7), 833–839. https://doi.org/10.1007/s00406-018-0921-3