Harnessing the Power of Light Therapy to Improve Mental Health
Light therapy is an effective and non-invasive treatment option for mental health conditions, particularly depression. With over 100 clinical trials supporting its efficacy, it has become a standard approach to managing seasonal and non-seasonal depression. This article explores the benefits of light therapy, how it works, and its role in managing various mood disorders.
What Is Light Therapy?
Light therapy, also known as phototherapy, involves exposure to bright, artificial light that mimics natural sunlight. This treatment was first discovered in the early 1980s at the National Institute of Mental Health (NIMH) and has since been widely used to treat Seasonal Affective Disorder (SAD) and other depressive disorders.
One of the reasons light therapy is so effective is that it helps reset the body’s biological clock, also known as the circadian rhythm, which regulates sleep and mood. The treatment can alleviate symptoms of depression and restore the body’s natural rhythm, especially for those who don’t have regular exposure to natural light.
How Light Therapy Works
When you use a light box, a device that emits light much brighter than typical indoor lighting, it stimulates the brain to produce hormones that regulate mood, such as serotonin, while reducing the production of melatonin, a hormone that induces sleep. Exposure to this bright light helps regulate your circadian rhythm, making it easier to wake up in the morning and feel more energized throughout the day.
The best time for light therapy is in the morning, between 5:00 a.m. and 8:00 a.m., depending on your natural waking preferences. The light helps "anchor" your internal clock, resulting in a mood boost and increased energy.
Who Can Benefit from Light Therapy?
While light therapy is most commonly used to treat seasonal depression (SAD), it has shown promise for other conditions, including:
Non-seasonal depression: Indoor living and limited exposure to bright, natural light can contribute to feelings of sadness and lethargy, which can be alleviated with light therapy.
ADHD, bulimia, dementia, and Parkinson’s disease: Research is exploring the potential of light therapy to treat other mental and neurological disorders, including cognitive and behavioral conditions.
Circadian rhythm disorders: Individuals suffering from jet lag, shift work, or delayed sleep phase disorder (extreme night owls) may also benefit from light therapy.
Choosing the Right Light Box
Not all light boxes are created equal. When selecting a light box, it’s essential to find one that emits at least 10,000 lux of light to mimic a sunny day and provide the best therapeutic effects. White light is the standard. Full spectrum lamps and blue (or bluish) lamps with color temperature above 5000 Kelvin are not superior in efficacy and cause increased visual glare. A large screen is preferable, and it should hang slightly overhead to deliver light from above. Avoid compact or slim devices, as they tend to be less effective due to insufficient light output.
Some recommended models include:
Northern Light Technology’s BOXelite OS ($180)
Carex’s Day-Light Classic or Classic Plus ($100–$140)
These models are widely used in clinical trials and offer the necessary intensity to treat depression.
How to Use Light Therapy
For best results, aim for 30 to 60 minutes of light exposure each day. Mild cases may require only 15 minutes, but it’s important to start gradually and increase exposure time as needed. Within 1 to 2 weeks, most people will notice improvements in their mood and energy levels.
If symptoms persist after four weeks, consider increasing the duration of therapy to up to two hours. It's also important to note that those with a strong seasonal pattern should start therapy two weeks before their usual depressive episodes begin.
Positioning Your Light Box
To maximize the effectiveness of light therapy, the light box should be positioned slightly above your head at a 30° angle. While under the light, you can go about regular activities such as reading or working, but avoid looking directly into the light to prevent eye strain. Make sure your head stays 10 to 14 inches from the light source for optimal exposure.
Safety Considerations
Light therapy is generally safe with minimal side effects. Some users may experience mild headaches, eye strain, or nausea, especially when first starting treatment. It’s also essential to use a light box with a diffusion screen to filter out harmful ultraviolet (UV) rays.
For those with photosensitivity or retinal conditions, blue light may pose a risk. Patients on photosensitizing medications like lamotrigine, antipsychotics, or tricyclic antidepressants should consult an ophthalmologist before starting light therapy.
Light Therapy for Bipolar Disorder
While light therapy is effective for depression, it requires caution in people with bipolar disorder. In these cases, early morning light exposure may trigger manic episodes. For individuals with bipolar depression, midday light therapy (between 12:00 p.m. and 2:00 p.m.) is recommended. This approach has been shown to reduce depressive symptoms without inducing mania.
If manic symptoms occur during treatment, it’s advised to decrease exposure time or switch to a midday schedule. In severe cases, the therapy may need to be stopped altogether.
Conclusion: A Bright Future for Light Therapy
Light therapy has become a valuable tool in the treatment of seasonal and non-seasonal depression, offering a natural alternative to medication. By harnessing the power of bright light, this therapy helps regulate sleep patterns, improve mood, and restore energy. While not without risks, especially for those with bipolar disorder, light therapy is generally well-tolerated and poses few side effects. With proper use and the right equipment, light therapy can be a bright spot in managing mental health.
Sources:
Aiken, Chris. "A Practical Guide to Light Therapy." The Carlat Report, November 15, 2019. CARLAT PUBLISHING.
Asai Y et al. "Outdoor Living, Morning Light, Evening Darkness, and Regular Rhythms of Sleep and Waking: Preventing Depression." Journal of Affective Disorders, 2018.
Mårtensson B et al. "Efficacy of Light Therapy in Treating Depression: A Meta-analysis." Journal of Affective Disorders, 2015.
Botanov Y, Ilardi SS. "Light Therapy for ADHD, Bulimia, and Other Disorders." PLoS One, 2013.
Penders TM et al. "Light Therapy as Augmentation in Depression Treatment." Primary Care Companion for CNS Disorders, 2016.
**Disclaimer
The information provided in this article is for educational purposes only and is not intended to serve as medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider before beginning any new treatment, including light therapy, to ensure it is appropriate for your specific health needs. The use of this information is at your own risk. The authors and publishers assume no liability for any injuries or damages resulting from the use or misuse of this information. Light therapy may not be suitable for everyone, especially those with pre-existing medical conditions, and it is essential to seek professional medical guidance before starting treatment.