Ty Johnston, PharmD Student
With winter just around the corner, many of us are wondering how to stay motivated, productive, and feeling good during the dark and cold months ahead of us. Well, there might be something that can help: light therapy, also known as phototherapy. Light therapy is essentially a light lamp that people expose themself to for a period of 30 minutes. Before breaking down the details, it is important to question whether one is experiencing the winter blues or seasonal affective disorder.
Winter Blues vs. Seasonal Affective Disorder
Seasonal affective disorder (SAD) is a form of depression that only occurs during typical seasons, such as winter. Although one may feel like their mood is low, whether due to the weather or not, it is likely they do not have depression or SAD. Depression/SAD is a disease where people experience a variety of symptoms in addition to feeling depressed, such as sleep and appetite changes that persist for a period of 2 or more weeks. People with diagnosed depression experience significant distress or functional impairment from important tasks, such as work, school, or social interactions. People who think they may be suffering from depression should seek advice from a healthcare professional.
Nonetheless, people suffering from depression or low mood can benefit from light therapy.
How and When It Works1
The truth is, nobody truly knows how light therapy works. However, it is thought that light therapy works by influencing neurotransmitters (chemicals) in the brain (e.g. serotonin and dopamine), which is similar to the way antidepressant medications work. Another possible way that it works is by influencing circadian rhythm, which is the clock in your in your body that tells you when to be tired or awake.
Usually it takes 1-3 weeks of using daily light therapy for people to see the benefits.2
Evidence
Light therapy has been shown to reduce depressive symptoms in people with depression and seasonal affective disorder.2,3,4 In the treatment of seasonal affective disorder it has been shown to be as effective as an antidepressant called fluoxetine.5
Risks
Light therapy is generally quite safe, however people can experience side effects such as headache, eye strain, irritability, and trouble sleeping.1
Additionally, light therapy may not be safe for those with bipolar disorder or medical conditions of the skin or eye. People with these conditions should talk to a healthcare professional before starting light therapy.
How is it best used?
The preferred dose is 10 000 lux of light for 30 minutes every morning. It is best used early in the morning with the light box tilted toward the face and about 12-14 inches from the eyes.1
People can engage in other activities as long as it does not interfere with the standard positioning.
Bottom Line
Light therapy has been proven effective in people who have been diagnosed with depression and seasonal affective disorder, but also has low risk and may benefit people who experience wintertime sadness.
We hope you took away something valuable from this piece. If you have any questions or concerns regarding this article or others, feel free to reach out to us on Instagram, Facebook, or at ask@orbishealth.ca with your feedback. We’d love to hear from you.
RESOURCES
- Dynamed Plus: Depression Alternative Treatments
- Ravindran AV, Lam RW, Filteau MJ, et al. (2009). Canadian Network for Mood and Anxiety Treatments (CANMAT) Clinical guidelines for the management of major depressive disorder in adults. V. Complementary and alternative medicine treatments. Journal of Affective Disorders.
- Lam RW, Levitt AJ, Levitan RD, et al. (2006). The Can-SAD study: a randomized controlled trial of the effectiveness of light therapy and fluoxetine in patients with winter seasonal affective disorder. American Journal of Psychiatry. 163(5).
- Tuunainen A, Kripke DF, Endo T. (2004). Light therapy for non-seasonal depression. Cochrane Database Systematic Reviews. 2.
- Martensson B, Pettersson A, Berglund L, Ekselius L. (2015). Bright white light therapy in depression: A critical review of the evidence. Journal of Affective Disorders. 182(1-7).
