Illuminating light therapy

Profiles of Norwegian science

light therapy

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While the science behind phototherapy is not fully understood, during the dark season, many Norwegians use light therapy to combat the winter blues.

Agder, Norway

Winter in Norway: fluffy flakes falling from above, a thousand lavenders painting dawn and dusk, the aurora’s dancing beauty, and depression that can lead to self-harm and suicide. 

Science contributes to understanding and addressing the adverse mental and physical health effects from weeks of limited daylight—and 24/7 darkness in northern Norway.

One intervention for these winter blues is light therapy. Technical terms refer to “winter-pattern seasonal affective disorder” (with the appropriate acronym SAD) treated by “phototherapy” and “heliotherapy.” People sit by a light box each day to be exposed to bright light without harmful ultraviolet rays, perhaps alongside seeing a therapist, medications, and dietary changes, especially vitamin supplements.

Another term is “triple chronotherapy” (TCT), which combines bright light therapy with sleep disruption to reset the body’s day-night rhythms. It shows possible promise for some people’s depression, although much remains under investigation.

Not much of the science is clear-cut. Scientific details of the causes, symptoms, treatments, and cures involve small study groups undertaking relatively new experiments struggling to make sense of a multitude of factors. 

Despite this research starting to take off nearly two generations ago leading to over 25,000 scientific publications to date, huge knowledge gaps remain. Caution is essential in interpreting results and applying recommendations.

It is the same situation for using light therapy for people having dark season health difficulties. In Norway, phototherapy has also recently been examined for conditions as diverse as jaundice in children and skin cancer. Meanwhile, “photobiostimulation” and “photobiomodulation” (among other terms) use targeted, low doses of light for healing wounds and treating depression.

Recent Norwegian science on light therapy for health woes has focused on hospital and care home settings.

One project published results this year, after collecting data over the winter of 2017-2018. Elisabeth Flo-Groeneboom at the University of Bergen led DEMLIGHT: Therapy Light Rooms for Improved Sleep in Dementia Patients. The research team tested simulated daylight influencing sleep patterns, moods, and behavior of people with dementia in long-term-care settings in Bergen. They also looked at impacts on the staff’s health and workload.

Conclusions so far are mixed. In the patients, some aspects of sleep and depression, but not all, improved after 16 weeks of light therapy, with further positive impacts on sleep after 24 weeks. Gender, age, other pre-existing medical conditions, and medications were considered, but the sample size was not large enough for complete and robust comparative analyses. Differences by race or ethnicity were not explored.

Farther north, and so with less winter sun, Håvard Kallestad in Trondheim leads research into using light with reduced blue to support psychiatric patients without negatively affecting staff’s working conditions. Reducing blue can be achieved with artificial bulbs, by wearing glasses that block blue wavelengths, or with filters over bulbs, windows, and televisions.

The research group demonstrates that careful use of indoor lighting with less blue seems to bolster some people in aspects of sleep and mood. More importantly, they set out a clear science agenda to examine how effects could depend on factors including diagnosis, medication, when people go to bed, type and intensity of light, and length of time and time of day for the light, among others.

What does all this mean for those either enjoying or just trying to get through the dark season? Ultimately, if light therapy works without side effects, then it would be hard to object. Conversely, without a specific diagnosis, we might preferably examine our day-to-day life in terms of stress, stressors, satisfaction, diet, exercise, relationships, quality of life, sleep interference, and overbearing expectations of productivity, success, and happiness.

Unfortunately for many (though not everyone), the inability to revel in the magical months of glittering snow, sparkling stars, and northern lights might come from society’s wider machinations to undermine control in and choices for our lives and livelihoods. Short days then become a trigger or added factor, rather than a true cause.

The key is differentiating among people’s different needs, conditions, and responses, especially to always ask for help whenever you feel you are in trouble in any way.

For immediate action: learn your local emergency and non-emergency medical and support numbers, so that you immediately make a phone call if you are feeling depressed.

This article originally appeared in the Dec. 17, 2021, issue of The Norwegian American.

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Ilan Kelman

Ilan Kelman is Professor of Disasters and Health at University College London, England, and Professor II at the University of Agder, Norway. His overall research interest is linking disasters and health, including the integration of climate change into disaster research and health research. Follow him at and @ILANKELMAN on Twitter and Instagram.