Hours of Sleep: Comparing the Impact of Phone Use Before Bedtime

Introduction

In today’s digital age, the pervasive use of smartphones and other screen-based devices has extended into our bedrooms, significantly impacting sleep patterns, especially among young individuals. It’s estimated that a considerable percentage of children and adolescents, specifically 30% of younger children and a majority of teenagers, experience insufficient sleep. This issue is compounded by the fact that a large proportion of young people have screen media devices in their bedrooms and frequently use them in the hour leading up to bedtime. This article delves into the science behind screen time and sleep, focusing on how pre-bedtime phone use affects sleep duration and overall sleep quality compared to abstaining from phone use. We will explore the current understanding of sleep needs, the prevalence of bedtime screen habits, the evidence linking screen use to sleep disruption, and the mechanisms through which screens interfere with sleep. Ultimately, we aim to provide evidence-based recommendations for fostering healthier sleep habits in the face of ever-present technology.

Sleep Requirements for Children and Adolescents

To understand the impact of phone use on sleep, it’s crucial to first establish healthy sleep duration guidelines. Two leading sleep organizations, the National Sleep Foundation (NSF) and the American Academy of Sleep Medicine (AASM), have developed consensus recommendations based on extensive research. These guidelines, formulated using a rigorous methodology, outline the recommended hours of sleep across different age groups. For children and adolescents, the recommendations are as follows:

Newborns (0-3 months): 14-17 hours per day
Infants (4-11 months): 12-15 hours per day
Toddlers (1-2 years): 11-14 hours per day
Preschoolers (3-5 years): 10-13 hours per day
School-aged children (6-13 years): 9-11 hours per day
Teenagers (14-17 years): 8-10 hours per day

It’s important to note that these are guidelines, and individual sleep needs may vary slightly. However, consistently falling short of these recommended hours can lead to significant consequences.

The Detrimental Effects of Insufficient Sleep on Wellbeing

Lack of adequate sleep, often exacerbated by phone use before bed, has far-reaching negative effects on cognitive, psychological, and physical health, particularly in developing children and adolescents.

Cognitive and Psychological Wellbeing: Sleep problems early in life are strong predictors of later mental health issues. Studies have linked short sleep duration in toddlers to behavioral and emotional problems later in childhood. Experimental research has shown that even short-term sleep restriction in teens can quickly worsen mood and emotional regulation. Furthermore, a meta-analysis suggests that sleep problems in adolescence can precede the onset of depression. This creates a potential vicious cycle where sleep issues and psychological problems worsen each other, a cycle that excessive screen media use can intensify.

Physical Wellbeing: Insufficient sleep is also strongly linked to physical health problems, most notably childhood obesity. Research consistently shows a connection between shorter sleep duration and increased risk of weight gain, and obesity in both children and adults. Studies have shown that infants sleeping less than the recommended hours are more likely to be overweight later in childhood. Experimental studies indicate that sleep restriction can lead to increased calorie consumption, especially of carbohydrates and fats, potentially explaining the link between sleep loss and obesity. Obesity, in turn, is a major health concern with long-term implications.

Bedtime Phone Habits: A Common Trend

Despite growing awareness of the negative effects of screen media on sleep, particularly phones, using electronics in the bedroom and around bedtime remains a common practice among young people. Surveys indicate that a significant percentage of children and adolescents have TVs in their bedrooms, with use extending to younger age groups. Alarmingly, some parents even report using bedroom TVs to help their children fall asleep, a practice that contradicts expert recommendations.

Data shows that media devices in bedrooms are more prevalent among lower-income youth, possibly due to factors like room sharing or differing family norms. National polls reveal that a large majority of young people keep electronic devices in their bedrooms, and a considerable portion of school-aged children and teenagers leave these devices on after bedtime, resulting in reduced total sleep time and poorer sleep quality.

Interestingly, many parents believe that watching TV helps young children “wind down” before bed, and adolescents often report using media at bedtime to aid sleep. This highlights a common misconception about the relaxing effects of screens before sleep, despite the evidence pointing to the contrary.

The types of screen media devices have also evolved rapidly, with a significant increase in tablet and smartphone ownership among young children. This shift towards more portable and interactive devices may have intensified the impact of screen media on sleep.

Screen Media and Sleep: Evidence of a Negative Relationship

A substantial body of research, encompassing over sixty studies, has investigated the relationship between screen time, including phone use, and sleep patterns in children and adolescents. The overwhelming consensus from these studies is that increased screen time is associated with delayed bedtimes and reduced total sleep duration. Many studies also point to links between screen use and poorer sleep quality, longer sleep onset latency (the time it takes to fall asleep), and increased daytime tiredness. One study even quantified that electronic media use accounts for a significant portion of the variation in adolescent sleep efficiency.

The timing of screen use appears to be crucial. Evening media use, especially in the hour or two before bedtime, has been shown to have a more pronounced negative effect on sleep compared to screen use earlier in the day. Furthermore, the content consumed also matters, with violent media potentially having a more disruptive impact.

A meta-analysis focusing specifically on portable screen-based media devices, like phones, confirmed a strong association between bedtime media use and insufficient sleep duration, poor sleep quality, and excessive daytime sleepiness. The mere presence of a portable screen device in the bedroom itself was linked to adverse sleep outcomes.

While most research focuses on typically developing children, studies on children with ADHD and Autism Spectrum Disorders show similar patterns, indicating the widespread impact of screen media on sleep across different populations. The negative associations have been observed with various screen devices, including TVs, computers, video games, smartphones, and tablets, reinforcing the broad impact of digital media on sleep.

Mechanisms: How Phones Disrupt Sleep

The negative relationship between phone use and sleep can be explained by several interconnected mechanisms:

Time Displacement: Using phones or other screens before bed directly displaces time that would otherwise be spent sleeping. Children and adolescents may delay bedtime to engage in screen entertainment, directly reducing their opportunity for sleep. This mechanism is particularly potent when screen use occurs close to bedtime, when sleep is the most likely activity being replaced.

Psychological Stimulation: The content consumed on phones, especially interactive content like games or social media, can be psychologically stimulating and arousing. Video games, in particular, can be highly engaging and even exciting, leading to increased physiological arousal. This arousal can interfere with the transition to sleep, making it harder to fall asleep and potentially affecting sleep quality. Even non-violent media can be stimulating enough to disrupt sleep for some individuals.

Light Exposure: Light emitted from phone screens, especially blue light, is a significant factor in sleep disruption. Exposure to screen light in the evening can:

Increase alertness and reduce sleepiness: Blue light suppresses the production of melatonin, a hormone that promotes sleepiness. This makes individuals feel more alert and less ready for bed, even when they are tired.
Disrupt sleep architecture: While research is still ongoing, some studies suggest that screen light may affect the different stages of sleep, potentially reducing the amount of restorative REM sleep.
Delay the circadian rhythm: Blue light exposure can shift the body’s natural sleep-wake cycle (circadian rhythm) to a later time. This makes it harder to fall asleep at an earlier bedtime and can lead to chronic sleep deprivation if wake-up times remain consistent.

Children and adolescents are particularly vulnerable to the effects of blue light because their eyes may be more sensitive to it than adults. Studies have shown that children experience greater melatonin suppression from the same levels of light exposure compared to adults, making them more susceptible to sleep disruption from phone use before bed.

Internet and Video Game Addiction: An Extreme Consequence

In some cases, technology habits, including phone and video game use, can become excessive and uncontrollable, leading to what is termed Internet and Video Game Addiction (IVGA). While not yet fully recognized as a formal disorder in all classifications, IVGA is gaining increasing attention due to its negative impacts, including severe sleep problems. Individuals with IVGA struggle to limit their internet or gaming use, resulting in psychosocial dysfunction and significant sleep disturbances like insomnia and insufficient sleep. The link between IVGA and poor sleep quality is particularly strong with massively multiplayer online role-playing games (MMORPGs), which are highly engaging and can consume vast amounts of time.

Individual Susceptibility: Not Everyone is Affected Equally

It’s important to recognize that individuals differ in their susceptibility to the negative effects of screen media on sleep. Some young people are more vulnerable than others. Factors like individual differences in physiological responses to screen use and personality traits can influence how screen time impacts sleep. For example, individuals who are more prone to risk-taking or have lower self-control may be more likely to delay bedtime due to extended screen use. Emerging research suggests that identifying these predisposing individual traits can help pinpoint youth who are most at risk of sleep disruption from technology habits.

Strategies and Interventions: Promoting Sleep-Friendly Screen Habits

Given the evidence, it’s clear that interventions are needed to mitigate the negative impact of phone use and screen media on sleep. The American Academy of Pediatrics (AAP) and the American Academy of Sleep Medicine (AASM) recommend keeping screen-based devices, including phones, out of children’s bedrooms and turning them off at least 30 minutes before bedtime. These are crucial steps in promoting healthier sleep habits.

Beyond simply limiting screen time, modifying media content can also be beneficial. Shifting children’s media exposure away from violent or highly stimulating content and towards educational or calming content may help reduce sleep problems.

While research on sleep interventions specifically targeting screen media is still developing, existing studies suggest that limiting screen time in the 30-60 minutes before bedtime can lead to modest improvements in bedtime and sleep duration. Comprehensive sleep hygiene programs that address multiple factors, including screen media use, have shown promise in improving sleep quality and regularity. One study demonstrated that restricting mobile phone use in the hour before bed resulted in earlier bedtimes and increased total sleep time in adolescents. However, implementing such restrictions can be challenging, highlighting the need for tailored and supportive approaches.

For adolescents with healthy sleep habits already, limiting screen media further may not show significant additional benefits. This underscores that interventions should be targeted towards those who are experiencing sleep problems related to screen use.

Clinician’s Perspective: Guiding Families Towards Healthy Habits

Clinicians play a vital role in helping families establish sleep-friendly screen habits. They can encourage authoritative parenting, characterized by warmth, support, clear limits, and developmentally appropriate autonomy. This parenting style fosters cooperation and shared goals for children’s health and wellbeing. Establishing family bedtime routines and healthy sleep habits early in life is crucial, adapting these routines as children mature.

For younger children, this involves setting clear household rules regarding screens and sleep. For older children and adolescents, open conversations about the reasons behind these rules and the benefits of healthy sleep are essential. This proactive and engaged parenting approach helps children develop self-regulation skills and eventually take ownership of their sleep health.

Sleep-Friendly Screen-Behavior Recommendations for Clinicians and Educators:

Discuss the importance of adequate sleep with families.
Recommend establishing healthy sleep habits from a young age.
Educate families about the negative effects of evening screen use on sleep.
Advise regular bedtimes that allow for sufficient sleep and calming bedtime routines without screens.
Recommend removing all screen devices from bedrooms.
Consider insufficient sleep as a contributing factor to mood, academic, or behavioral problems.
Encourage children to develop self-regulation skills for healthy screen habits.

Sleep-Friendly Screen-Behavior Recommendations for Parents:

Parents can draw inspiration from health psychology principles, similar to promoting healthy eating habits. Instilling healthy “screen media diet” from a young age, rather than imposing rigid restrictions later, is more effective. Parental role modeling is crucial, and a health-risk prevention approach is more effective than reactive measures. Setting age-appropriate norms and boundaries with parental warmth, rather than resorting to discipline after problems arise, is key. Fostering autonomy empowers teenagers to take responsibility for their healthy lifestyle choices.

For teenagers struggling with excessive screen time, clinicians can focus on the primary concerns, such as poor academic performance, which may be linked to sleep deprivation due to late-night screen use. Addressing underlying stressors driving screen use is important. Clinicians should collaborate with families to implement structural and behavioral changes to reduce evening screen media use and improve sleep. Educating adolescents about the benefits of sufficient sleep and the negative consequences of sleep deprivation can motivate them to change their habits. Highlighting the impact of sleep on areas important to them, like concentration, athletic performance, or body weight, can be effective. Crucially, removing screen devices from bedrooms eliminates the temptation for nighttime use.

Changing bedtime screen media habits is a challenge, but by using these strategies, clinicians and parents can work together to promote healthy sleep habits that will benefit children and adolescents throughout their lives.

Recommendations for a Healthier Sleep Future

Based on current research and clinical understanding, adopting “sleep-friendly screen behaviors” is crucial for minimizing the negative impact of screen media on youth sleep. This includes:

Restricting screen exposure in the hour before bedtime.
Turning off devices completely at night.
Keeping devices out of the bedroom.
Modifying media content to reduce psychological stimulation.

Future Research Directions

While current research highlights the threat of screen media to youth sleep, more research is needed to develop and evaluate effective and sustainable interventions. Exploring strategies to address the fear of missing out (FOMO) associated with social media and online activities may be particularly beneficial for improving adolescent sleep. Further basic, translational, and clinical research is essential to fully understand the complex relationship between screen media, sleep, and health outcomes in children and adolescents. This knowledge is vital for educating and motivating parents, clinicians, educators, and young people themselves to prioritize and foster healthy sleep habits in the digital age.

Key Points

Extensive research links screen media use in youth, especially before bedtime, to shorter sleep duration and delayed sleep onset. Bedroom access to screen devices worsens sleep outcomes.
Mechanisms include time displacement, psychological stimulation, and the alerting effects of screen light.
Clinicians, educators, and parents should emphasize regular bedtime routines and “sleep-friendly screen behaviors”: limiting pre-bedtime screen use, turning off devices at night, and keeping devices out of bedrooms.
Further research is needed to develop effective interventions and understand the long-term impacts of screen media on youth sleep and health.

Acknowledgments

The authors express gratitude to Guest Editor, Paul Weigle, MD, for his valuable review and feedback on this manuscript.

Footnotes

Disclosures: Authors were partially supported by grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) of the National Institutes of Health. Dr. Buxton has received subcontracts from Mobile Sleep Technologies. Dr. Gradisar has received consultancies from various organizations.

Publisher’s Disclaimer: This is an early version of a manuscript accepted for publication and may undergo further editing and review.