Big Claims, Thin Evidence
The holidays are upon us, and we can soon expect the media to begin warning us of the holiday blues. Scholarly reviews of media coverage find that reporting on mental health often relies heavily on anecdotal evidence, personal stories, and oversimplified causes such as holiday stress, while underreporting scientific sources. Yearly recycling of these news stories has created a widespread belief in the existence of Seasonal Affective Disorder (SAD) or “winter-blues,” while the scientific evidence is at best mixed.
Latitude, Sunlight, and Depression: The Expected Pattern That Didn’t Appear
The first to introduce the concept of SAD and treatment with “light therapy” was Norman E. Rosenthal, MD, a psychiatrist at the National Institute for Mental Health, in 1984. Since then, according to Google Scholar, there have been 81 subsequent scholarly publications.
A 2016 analysis of CDC data was one of the earliest studies questioning the validity of SAD. Relying on a large, cross-sectional sample of 34,294 Americans in a year-long study, researchers examined the incidence of depression, as assessed by a self-reported depression scale, in relation to latitude, a measure of location north or south of the equator. During the winter months in the United States, the hours of daylight gradually decrease until the vernal equinox on December 21st. If SAD is a valid construct, one would expect the incidence of depressive symptoms to increase as the amount of daily sunlight decreases. The data revealed that depression was unrelated to latitude, season, or sunlight.
Suicide Rates Don’t Spike in December
The incidence of suicide, which is significantly higher in those suffering from depression, also varies by month. One might expect suicide rates to increase in December, but the rates are actually the lowest in December. Over 15 years, serving as a consultant to a busy Emergency Room evaluating close to 4,000 suicidal patients, the month of December was consistently the month when I received the fewest requests for my consulting services. The months when suicide is the most frequent are late spring and summer months, when sun exposure is highest. Perhaps “Suicide Prevention Month” should be moved to May!
As a final note on the relationship of depression to sunlight exposure, there are peer-reviewed scientific studies (here and here) that examine whether weather conditions (sunlight, cloud cover, temperature, etc.) correlate with suicide risk or suicidal behavior. The evidence is mixed, but some data suggest sunny days or lower cloud cover may be associated with a modestly higher risk of suicide.
Holiday Blues “Real”? For Some—Not for Most
The subject of “Holiday Blues” is much less well-studied scientifically. Like the SAD research, the evidence is “mixed” and even more often anecdotal. The cultural narrative of “holiday blues” relies heavily on self-selected surveys, media recall bias, and blending of multiple potential stressors (weather, daylight, financial pressures, family stress, grief over the anniversary loss of a loved one). Absent is hard data that could support a well-defined clinical phenomenon.
Since Thanksgiving is the busiest travel time of the year and Christmas is a close second, many American families reconnect. The holidays are also typically associated with salutogenic factors, promoting resiliency and mental well-being rather than distress. Thanksgiving reminds us to be thankful, and large-scale studies of gratitude have shown that it reduces depression and anxiety by shifting our attention away from threats and negative biases, which the brain is naturally more attuned to. Spending time with family and friends increases oxytocin, reduces cortisol, and improves mood. Shared holiday rituals (meals, traditions, decorations) provide a stable framework for identity, belonging, and social coherence. Holiday parties offer opportunities for social support, which is one of the strongest protective factors against depression and suicide year-round.
There is no doubt that the winter season is not free from depression. Holidays can also be a stressful time, particularly in the absence of a loving family or the presence of toxic families. Financial strain and sleep loss can also affect mood, though unlikely to trigger a mood disorder in the absence of other factors known to contribute to depression. Based on meta-analytic evidence, approximately 5% of Americans suffer from seasonal depression. The good news is that 95% don’t!
None of this means winter is magically stress-free, or that the holidays can’t be painful—especially for people facing grief, isolation, family conflict, financial strain, or disrupted sleep. But as a broad, supposedly predictable national phenomenon, “holiday blues” is more of a cultural storyline than a clinical diagnosis. For many people, the season contains built-in protective factors: connection, ritual, belonging, and social support—powerful buffers against depression and suicide year-round. The most accurate takeaway is balanced and practical: take distress seriously when it shows up, but don’t assume the calendar itself is a mental-health verdict for “most Americans.”
Timothy Spruill, Ph.D
Dr. Spruill completed his doctorate in Counselor Education & Counseling Psychology and accepted a graduate faculty position at Andrews University serving for 7 years as an associate professor of counseling psychology. In 1998, he joined the Osteopathic Family Medicine residency faculty at AdventHealth in Orlando in the Department of Psychiatry. He has served as a consultant to the Emergency Department.
