Blue light: one of the biggest threats to quality sleep.
Here are 4 ways to block those inconvenient light waves and catch better Z's.
Let's Start at the Beginning
Early humans experienced predictable periods of light and dark from the solar day. Their circadian rhythms, or internal body clocks, were synced to the environment’s light-dark cycles.¹ As a result of the increasing use of artificial light, it has become more difficult for us to synchronize our biological processes. Exposure to artificial light at night, including through television and cell phones, has effectively “blurred the boundaries of day and night.”²
Blue wavelengths are helpful during the daytime because they boost attention, reaction times, and mood.³ However, blue wavelengths are detrimental to our health and well-being when used at night.
How does blue light affect my well-being?
Studies have shown direct and indirect connections between exposure to blue light at night and mood.⁴ A study found that mice developed behavioral symptoms reminiscent of depression after artificially manipulating their light environment.⁵
Another study found that blue light exposure at home was significantly associated with depressive symptoms in an elderly human population.⁶ Their findings implied that blue light may have even greater effects in younger people, as there is decreased light reception to the retina with age.⁷
Blue light at night is associated with sleep disruption. Exposure to light at night strongly suppresses melatonin, a hormone that promotes sleep onset, which interferes with sleep timing and sleep quality.⁸ Sleep disruption has been found to contribute to the onset and maintenance of mood disorders.⁹
How do I protect myself from blue light?
Put all screens away before bed. Avoid looking at screens two to three hours before bed, preferably.¹⁰ If this cant be done, try to limit screen use as much as possible at for at least an hour.
Block the blue light that comes from your electronics. If you use electronics at night, consider wearing blue light blocking glasses, sleep masks, or installing an app that filters the blue light.¹¹
Change your night light. Opt for a dim red night light. Red light is the least likely wavelength to affect circadian rhythms and suppress melatonin.¹² Melatonin, a sleep agent released in your brain, is triggered by the dark.
Invest in blackout curtains. Blackout curtains block outside light and are helpful if your bedroom is susceptible to light exposure from your window at night.¹³
Endnotes
Bedrosian, T. A., & Nelson, R. J. (2017). Timing of light exposure affects mood and brain circuits. Translational Psychiatry, 7(1). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5299389/.
Ibid.
Blue light has a dark side. (2012, May). Retrieved from https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side
Bedrosian, T. A., & Nelson, R. J. (2017). Timing of light exposure affects mood and brain circuits. Translational Psychiatry, 7(1). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5299389/.
LeGates TA, Altimus CM, Wang H, Lee HK, Yang S, Zhao H et al. Aberrant light directly impairs mood and learning through melanopsin-expressing neurons. Nature 2012; 491: 594–598. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3549331/.
Obayashi, K., Saeki, K., & Kurumatani, N. (2018). Bedroom Light Exposure at Night and the Incidence of Depressive Symptoms: A Longitudinal Study of the HEIJO-KYO Cohort. American Journal of Epidemiology, 187(3), 427–434. Retrieved from https://academic.oup.com/aje/article/187/3/427/4056592.
Ibid.
Bedrosian, T. A., & Nelson, R. J. (2017). Timing of light exposure affects mood and brain circuits. Translational Psychiatry, 7(1). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5299389/.
Ibid.
Blue light has a dark side. (2012, May). Retrieved from https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side
Ibid.
Ibid.
Bedrosian, T. A., & Nelson, R. J. (2017). Timing of light exposure affects mood and brain circuits. Translational Psychiatry, 7(1). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5299389/.