Lack of sleep bad for overall health in teens

Sleep experts warned that lack of sleep among teens can adversely impact their well-being across the board, including physical and mental health, and that too much time spent on device is a culprit displacing normal sleep time of teens, as reported in a review article.

 “Getting enough sleep is important for all of us — it helps our physical and mental health, boosts our immunity, and ensures we can function well on a daily basis,” said lead author Dr Alex Agostini from University of South Australia in Adelaide, Australia.

“But for teenagers, sleep is especially critical because they’re at an age where they’re going through a whole range of physical, social, and developmental changes, all of which depend on enough sleep,” he continued.

Teenagers typically require 8 hours of sleep per night, wrote Agostini and co-author in the review. [Child Adolesc Psychiatr Clin N Am 2021;doi:10.1016/j.chc.2020.08.011] Teenagers who slept less than 8 hours per night had poorer academic performance, particularly in mathematics and language skills. Moreover, insufficient sleep may indirectly affect academic achievement by lowering learning motivation. [J Adolesc 2013;36:311-318; Pers Individ Dif 2013;54:836-840]

In addition, getting enough sleep is also important for maintaining physical health. A study has shown that teenagers who slept longer fell ill less often than those who slept less across a 16-week period. [J Sleep Res 2014;23:133-142]

One mechanism underlying this observation is that insufficient sleep may lead to a weakened immune function, and thus, increased infections. Another study supporting this showed that sleep deprivation was associated with decreased levels in hormones that are necessary for healthy functioning of the immune system. [J Allergy Clin Immunol 2005;116:1188-1198; Sleep Med Rev 1999;3:219-228]

Not only was insufficient sleep bad for physical health, it can also be detrimental for mental health. Researchers found that teenagers who slept less than 8 hours per night were more likely to feel sad or hopeless and consider suicide compared with their peers with longer sleep duration. [Prev Med 2011;53:271-273]

“[Without sufficient sleep, teenagers are] less able to deal with stressors, such as bullying or social pressures, and run the risk of developing behavioural problems, as well as anxiety and depression,” said Agostini.

“If sleep drops to less than 6 hours a night, research shows that teens are twice as likely to engage in risky behaviours such as dangerous driving, marijuana, alcohol or tobacco use, risky sexual behaviour, and other aggressive or harmful activities.”

One culprit leading to sleep deprivation among teenagers in the digital age is mobile device. Access to these devices in the bedroom has been associated with significantly reduced sleep quantity as well as sleep quality in children. [Sleep Health 2015;1:15-27; J Sch Nurs 2012;28:469-476; Sleep 2004;27:101-104]

“Teens spend a lot of time on devices, whether it’s texting friends, playing games, or watching videos, using technology late into the night is one of the most common disruptors of good sleep. Overuse of technology can also contribute to mental health issues likely to increase anxiety,” said study co-author Dr Stephanie Centofanti, also from University of South Australia.

“Not only can technology use make us feel anxious and awake, but the blue light emitted from technology inhibits the production of the sleep hormone melatonin to delay the natural onset of sleep,” she explained. “This is problematic because teens already have a biological tendency to want to stay up late and sleep in.”

“To make a real difference to teenage mental health, both parents and medical practitioners must understand how sleep can affect mental health in teenagers,” she stressed.