Is light at night making your teen depressed?
According to the CDC, about 15 percent of teens report they’ve considered hurting themselves over the past 12 months. Suicide rates in adolescents have tripled in the last few decades and climbed even further during the last several years. Experts speculate that bullying, and in particular cyberbullying, is a major driver behind the rise.
But while the subject of bullying has received media attention leading to more research and improved resources, another more insidious culprit lurks undetected: the ubiquitous use of screen media by adolescents at night, aka “light at night.”
- Researchers in Japan found suicidal feelings and self-injurious behavior in adolescents were associated with cell phone use after lights-out
- The CDC's Youth Risk Behavior Survey of 2007 and 2009 linked teen sadness and suicidality to video game and internet overuse
- Research on Taiwanese adolescents revealed links between problematic cell phone use, disturbed sleep, and risky behaviors including suicidality
- A Johns Hopkins animal study found that light at night increased depressive symptoms, such as high cortisol levels (stress hormone), reduced pleasure-seeking, and lethargy
The correlation between light at night, depression, and suicidality is not surprising. Consider the following: sleep disturbance (including irregular sleep patterns, nightmares and nighttime awakenings) predicts suicidality behavior and suicide completion in adolescents. Excessive screen-time in general is associated with depression and other psychiatric disorders,  and screen-time disturbs sleep—a major issue with adolescents. Furthermore, a recent Harvard Health newsletter discussed how light-at-night from electronics and even energy-efficient lightbulbs[*] disrupts sleep rhythms and harms health, highlighting the ever-growing influence of technology on mental health.
Removing light-at-night sources is an essential intervention
Light at night may contribute to depression and suicidal thoughts and gestures by suppressing sleep signals, elevating stress hormones, altering mood chemistry, and disrupting the body’s internal rhythms (the subject of a future post). When it comes to addressing teen depression in today’s world, conventional treatments are not enough. Electronic light-at-night devices (smartphones, laptops, iPads, tablets, televisions) are a ubiquitous and overlooked factor in depression and suicide, and their removal from the bedroom should be a mandatory component of any treatment plan. This includes implementing an “electronics check-in” time every evening, including phones and other handheld devices. Keeping all mobile devices for the entire family in one place at night will help with compliance.
Your child’s screen “rights” vs. health and safety
When I work with parents of teens and young adults, many of them are reluctant to remove electronics from the child’s bedroom: “It’s his TV, he bought it with his own money.” Or “Her dad got her that phone, so I can’t really take it away from her.” Or “He’s an adult now. What can I do?” But we know the brain’s frontal lobe is still actively developing through the mid-twenties, so you must assume that your child’s brain is not mature enough to exert good impulse control. If a screen device is in the room, he or she will use it. Even with young adults, the no-screens-at-night and no-screens-in-bedroom rules fall under a bigger rule: “As long as you’re living in my house, you need to follow house rules. Period.”
Modern times call for modern measures. If you’re the parent of a depressed teen, addressing light at night can help lift your child’s mood—and may even save your child's life.
For more help with addressing screen-time in depressed children and teens, see Reset Your Child's Brain: A Four Week Plan to End Meltdowns, Raise Grades and Boost Social Skills by Reversing the Effects of Electronic Screen-Time.
[*]Electronics and energy-efficient bulbs (i.e. LED screens and CFL & LED lightbulbs) emit relatively large amounts of blue wavelength light, which suppresses melatonin more strongly than red light spectrum.
 Centers for Disease Control and Prevention. Youth Risk Behavior Surveillance: United States, 2011, Morbitity and Mortality Weekly Report, June 8, 2012, http://www.cdc.gov/mmwr/pdf/ss/ss6104.pdf.
 Norihito Oshima et al., “The Suicidal Feelings, Self-Injury, and Mobile Phone Use After Lights Out in Adolescents,” Journal of Pediatric Psychology 37, no. 9 (October 1, 2012): 1023–30, doi:10.1093/jpepsy/jss072.
 Yuan-Sheng Yang et al., “The Association between Problematic Cellular Phone Use and Risky Behaviors and Low Self-Esteem among Taiwanese Adolescents,” BMC Public Health 10 (2010): 217, doi:10.1186/1471-2458-10-217.
 Johns Hopkins. "Exposure to light at night may cause depression, learning issues, mouse study suggests." ScienceDaily. ScienceDaily, 14 November 2012. <www.sciencedaily.com/releases/2012/11/121114133921.htm>.
 Nisse Sjöström, Margda Waern, and Jerker Hetta, “Nightmares and Sleep Disturbances in Relation to Suicidality in Suicide Attempters,” Sleep 30, no. 1 (January 2007): 91–95.
 Neel Koyawala et al., “Sleep Problems and Suicide Attempts Among Adolescents: A Case-Control Study,” Behavioral Sleep Medicine, March 21, 2014, doi:10.1080/15402002.2014.888655.
 Xianchen Liu, “Sleep and Adolescent Suicidal Behavior,” Sleep 27, no. 7 (November 1, 2004): 1351–58.
 Tina R Goldstein, Jeffrey A Bridge, and David A Brent, “Sleep Disturbance Preceding Completed Suicide in Adolescents,” Journal of Consulting and Clinical Psychology 76, no. 1 (February 2008): 84–91, doi:10.1037/0022-006X.76.1.84.
 Mark W Becker, Reem Alzahabi, and Christopher J Hopwood, “Media Multitasking Is Associated with Symptoms of Depression and Social Anxiety,” Cyberpsychology, Behavior and Social Networking 16, no. 2 (February 2013): 132–35, doi:10.1089/cyber.2012.0291.
 Junghyun Kim, Robert LaRose, and Wei Peng, “Loneliness as the Cause and the Effect of Problematic Internet Use: The Relationship between Internet Use and Psychological Well-Being,” Cyberpsychology & Behavior: The Impact of the Internet, Multimedia and Virtual Reality on Behavior and Society 12, no. 4 (August 2009): 451–55, doi:10.1089/cpb.2008.0327.
 Takeshi Munezawa et al., “The Association between Use of Mobile Phones after Lights out and Sleep Disturbances among Japanese Adolescents: A Nationwide Cross-Sectional Survey,” Sleep 34, no. 8 (August 2011): 1013–20, doi:10.5665/SLEEP.1152.