For many, the changing of seasons takes a direct toll on mental health. Seasonal affective disorder, or SAD, is a common depressive mental disorder that is most often brought on by winter (Melrose, 2015).
Seasonal affective disorder influences our physiology. Neurologically, our brains may prevent the production of serotonin, the neurotransmitter linked to elevated moods (Melrose). Our bodies may also overproduce Melatonin, the sleep hormone. This makes us drowsy throughout the day and throws off our natural circadian rhythm.
On the outside, seasonal depression and SAD include consistent irritability, difficulty concentrating, a sense of restlessness, and over/under eating, and oversleeping. Oversleeping and chronic fatigue are two of the most common symptoms. With the darker and colder days, your bed or couch appears more desirable than the outside world.
Women are generally more at risk of being affected by seasonal affective disorder. They are four times more likely to suffer from it than men (Melrose). In addition, the farther you live from the equator, the more likely you are to suffer from seasonal depression/SAD. For example: 1% of Floridians report experiencing SAD, but 9% of Alaskans face symptoms of SAD (Melrose).
There are a variety of methods to treating the symptoms of seasonal depression/SAD. It can range from simple scheduling to counseling. The easiest, most accessible method to help alleviate seasonal affective disorder is to make up for lost sunlight by use of light therapies.
We’ve previously written about the positive impact nature has on mental health. This aligns with the idea that spending time in the sun can lift your mood. If you live in the North, the sun takes a little extra time rising over mountains or trees and dips below them quicker than we might like. Even if your area lacks natural sunlight, you can easily make up for it with an artificial blue or white light.
Meesters et al. (2016) studied the difference between blue light or white light exposure and found both effective to treat SAD. Study participants did not report a preference in the color of light. Participants completed 20 minutes of exposure to morning light for five straight days, which significantly improved mood, energy levels, and reduced fatigue and hypersomnia (sleepiness) symptoms.
Veleva et al. (2018) reviewed several studies to examine the effect of ultraviolet light has on depressive symptoms in general. Two weeks of daily, safe exposure to UV light helped elevate mood and reduced depression symptoms. Results were the same regardless of whether the light came from natural light or artificial sources.
Wake therapy, or purposefully depriving oneself of sleep, is another method of effectively combating seasonal depression.
While light therapy is useful for combating symptoms such as depressive thoughts and negative attitudes, wake therapy can help fight the desire to stay in bed and also keep a person’s circadian rhythm balanced. Using a combination of these two therapies can ultimately offset the winter blues and alleviate many of the symptoms of SAD.
Getting more light and regulating your sleep schedule may be easier said than done. One of the many reasons why seasonal affective disorder is so hard to overcome is because it is so easy to convince yourself the winter is truly an awful season. Cognitive behavioral therapy techniques, on top of utilizing light or wake therapy, can retrain those negative thoughts.
In their study combining both cognitive-behavior therapy (CBT) and light therapy, Meyerhoff et al. (2018) found that light therapy helped reduce symptoms of insomnia, psychic anxiety, hypersomnia, and social withdrawal faster than CBT alone could. This supported the claim that SAD mainly develops because the body’s circadian rhythm is offset during the winter. But, the two were most effectively done together. CBT can be used as a supplement to address more psychological symptoms of SAD (Meyerhoff et al.).
Similarly, the American Psychological Association published a clinical trial that showed the benefits of both CBT and light therapy on those suffering from SAD. Light therapy proved to be helpful in reducing distaste towards the dark/nighttime, while CBT treatment helped patients change their maladaptive beliefs towards the colder seasons (Rohan et al., 2020). Again, this shows that used together, light therapy addresses the physiological aspect of SAD, while CBT addresses the psychological side.
Research has gone back and forth asking this very question. Science cannot credit vitamin D alone towards positively alleviating symptoms of seasonal affective disorder. The National Center for Complementary and Integrative Health (NCCIH, 2019) reported that those suffering from SAD have lower levels of vitamin D, either from lack of dietary intake or lack of sunlight exposure. While seasonal depression and lack of vitamin D are associated, there is no evidence that low levels of vitamin D is the cause for depressive thoughts and behaviors. Perhaps the best way to increase vitamin D levels is to do so naturally while getting exposed to light as part of light therapy.
Thomas and Al-Anouti (2018)’s research suggested that sun-derived vitamin D can help decrease the prevalence of depressive symptoms in individuals with SAD. 114 college women were screened for both symptoms of SAD and vitamin D deficiency. For two weeks, participants had to increase their sun exposure by eating breakfast outdoors, parking farther away from entrances, and sitting by the window more often (Thomas & Al-Anouti). Results showed that the experimental group was no longer vitamin D deficient and depressive symptoms were also significantly reduced (Thomas & Al-Anouti). Such simple actions to increase your sun exposure may improve your symptoms as well.
Thankfully, seasons come and go. When you’re in the middle of a dark and lonely winter, remember to find the sun as much as you can. If you’re experiencing more serious forms of depression, please contact the SAMHSA hotline.
Practicing self-care can also help you during those winter months. LIFE Intelligence is a self therapy app that provides free cognitive behavioral therapy (CBT) and other coping and problem-solving exercises for emotional management. It can help you understand more about depression, learn how sleep, diet, and perspective can affect stress or anxiety, and develop more self-awareness in what makes you feel SAD. From mood tracking to breathing exercises, use LIFE Intelligence to fight the winter blues. You can also keep track of your personal goals - even if your only goal is to get out of bed or to take a walk in the sun.
Kragh, M., Martiny, K., Videbech, P., Møller, D. N., Wihlborg, C. S., Lindhardt, T., & Larsen, E. R. (2017). Wake and light therapy for moderate-to-severe depression - a randomized controlled trial. Acta Psychiatrica Scandinavica, 136(6), 559–570.
Martiny, K., Refsgaard, E., Lund, V., Lunde, M., Sørensen, L., Thougaard, B., Lindberg, L., & Bech, P. (2013). The day-to-day acute effect of wake therapy in patients with major depression using the HAM-D6 as primary outcome measure: results from a randomised controlled trial. PloS one, 8(6), e67264.
Meesters, Y., Winthorst, W. H., Duijzer, W. B., & Hommes, V. (2016). The effects of low-intensity narrow-band blue-light treatment compared to bright white-light treatment in sub-syndromal seasonal affective disorder. BMC Psychiatry, 16, 1–10.
Melrose, S. (2015). Seasonal Affective Disorder: An overview of assessment and treatment approaches. Depression Research and Treatment, 2015.
Meyerhoff, J., Young, M. A., & Rohan, K. J. (2018). Patterns of depressive symptom remission during the treatment of seasonal affective disorder with cognitive-behavioral therapy or light therapy. Depression & Anxiety (1091-4269), 35(5), 457–467.
National Center for Complementary and Integrative Health. (2019, June). Seasonal affective disorder.
Rohan, K. J., Burt, K. B., Camuso, J., Perez, J., & Meyerhoff, J. (2020). Applying experimental therapeutics to examine cognitive and chronological vulnerabilities as mediators of acute outcomes in cognitive-behavioral therapy and light therapy for winter depression. Journal of Consulting & Clinical Psychology, 88(8), 786–797.
Thomas, J., & Al-Anouti, F. (2018). Sun exposure and behavioral activation for hypovitaminosis D and depression: A controlled pilot study. Community Mental Health Journal, 54(6), 860–865.
Veleva, B. I., van Bezooijen, R. L., Chel, V. G. M., Numans, M. E., & Caljouw, M. A. A. (2018). Effect of ultraviolet light on mood, depressive disorders and well‐being. Photodermatology, Photoimmunology & Photomedicine, 34(5), 288–297.