01/11/2026
From 1440 news:
Winter Blues
Can the seasons really make you depressed?
Seasonal affective disorder is a form of depression that repeats during predictable seasonal shifts, impacting an estimated 5% of the global population—predominantly women. Symptoms of the condition occur with significant cyclical changes in daylight hours, with prevalence increasing in regions north of 40 degrees latitude (less commonly in the Southern Hemisphere). Its etiology—or root cause—remains unclear to researchers.
Though “winter blues” are commonly reported, SAD is a distinct, diagnosed subtype of major depressive disorder first formally described in 1984 (see criteria). Key symptoms—lasting roughly four months each year—resemble common depression: fatigue, increased sleep, carbohydrate cravings, and social withdrawal. Researchers argue most cases develop from a circadian rhythm phase delay disorder resulting from reduced daylight, disrupting the production of serotonin and melatonin—key neurotransmitters that regulate mood. SAD often arises as part of a broader complex of mood conditions.
Effective forms of treatment include bright light therapy—where individuals bask in strong artificial light for at least 30 minutes each morning—cognitive behavioral therapy (attempting to rewire negative thoughts about winter), and antidepressants like bupropion.
.. Read what else we learned about the condition here.
Also, check out ...
> Ten percent of SAD cases occur in the summer. (Read)
> SAD's timing is uniquely predictable among depressive disorders. (Listen)
> Women are four times more likely to be diagnosed with SAD. (Read)