Screen time duration and timing: effects on obesity, physical activity, dry eyes, and learning ability in elementary school children

Abstract

Background As internet use becomes more widespread, the screen time (ST) of elementary school students increases yearly. It is known that longer durations of ST can affect obesity, physical activity, dry eye disease, and learning ability. However, the effects of ST just before bedtime have not been clarified. Therefore, we examined ST duration and timing effects on elementary school children. Methods We conducted a survey of 7419 elementary school students in Tokyo, Japan using a questionnaire on food education. ST duration and timing (just before bedtime) served as the explanatory variables, and the relationship between obesity, physical activity, dry eyes, and learning ability was analyzed using logistic regression analysis. Gender, school year, height, and weight were considered confounding factors. First, we examined whether ST duration and timing were related to each objective variable, using a univariate model to examine all variables. Thereafter, we performed multivariate logistic regression analyses for all variables showing a significant difference in the univariate models. Results A significant association was observed between ST duration and obesity, physical activity, and academic performance, indicating that a longer ST duration may lead to obesity, decreased physical activity, and decreased academic performance. ST timing was associated with obesity, dry eyes, and academic performance, and ST immediately before bedtime contributed to obesity, dry eyes, and reduced academic performance. Furthermore, the results of investigating the combined effect of ST duration and timing (immediately before bedtime) on these factors revealed that ST timing has a greater effect on dry eyes, and ST duration has a greater effect on academic performance. Conclusion Our findings indicate that ST in school children is related to obesity, physical activity, dry eyes, and learning ability, and they suggest that not only the duration but also the timing of ST is important.

Parental Self-Efficacy—A Predictor of Children's Health Behaviors? Its Impact on Children's Physical Activity and Screen Media Use and Potential Interaction Effect Within a Health Promotion Program

“…For instance, there is a clear association between children's television viewing of more than 2 h per day and lower well-being, less self-control and emotional stability (Twenge and Campbell, 2018), decreased fitness (Hardy et al, 2018), lower school and academic performance (Howie et al, 2020;Mineshita et al, 2021), reduced social skills (Hinkley et al, 2010), cardio-vascular diseases (Lissak, 2018) as well as mental and social disorders (Pagani et al, 2016;Stiglic and Viner, 2019).…”

Digital Devices and Cognitive Functions in Children

“…Уже к 2010 г. рекомендованные ВОЗ лимиты были превышены в Японии (к 18 мес 86% детей проводили перед телевизором более 1 ч/сут) [27] Другая картина наблюдается в связи со школьной (академической) успеваемостью. Множество исследований в разных странах (США [31], Канада [32], Великобритания [33], Нидерланды [34,35], Испания [36,37], Австралия [38], Япония [39,40], Южная Корея [41], Китай [42]) демонстрируют связь более длительного экранного времени и использования электронных гаджетов детьми с их низкой успеваемостью. При этом в указанных источниках это установлено в отношении общего экранного времени, а также для использования мобильных телефонов / смартфонов [33,36] и социальных сетей [34,35].…”

Increased Screen Time and Dry Eye: Another Complication of COVID-19

“…The long-term effects of this increase in electronic device use on physical and mental health are unknown and will take years to determine. Before COVID-19, the negative effect of prolonged screen time on the health of the ocular surface was known 1 and the increased use of electronic devices necessitated by the pandemic will exacerbate this problem. 2 In addition, once the current health crisis subsides, many people will continue to work, learn, and socialize remotely through electronic devices so that the effect of screen time on the ocular health will continue to be an issue for the foreseeable future.…”

“… 3 This is also true for patients of almost all ages; before COVID-19, in 2018, Sheppard and Wolffsohn 4 reported that 68% of children regularly use a computer by age 3 and 37% of adults aged 60 years and older spend 5 or more hours daily on digital devices. Mineshita et al's 1 recent study of 7,419 elementary school children in Japan found that, in addition to dry eye, increased screen time is associated with obesity, decreased physical activity, and reduced academic performance.…”

“… 7 , 8 Some monitors offer the option of “night light” (Microsoft) or “night shift” (Apple) screen settings, but there are no data as to whether these settings mitigate the risk to the ocular surface of screen time in general. 1 When setting up workstations, people should position their screens to look downward instead of upward or straight ahead to decrease the palpebral aperture.…”