Weekday Television Research Articles

Childhood and Adolescent Television Viewing and Metabolic Syndrome in Mid-Adulthood.

Excessive sedentary behaviors, such as television viewing or other screen time, may have adverse metabolic effects. We hypothesized that television viewing time in childhood would be associated with the risk of metabolic syndrome at 45 years of age. We studied a population-based birth cohort born in Dunedin, New Zealand in 1972 and 1973. Parent- and self-reported weekday television viewing times were recorded at ages 5, 7, 9, 11, 13, 15, and 32 years. The primary outcome was metabolic syndrome at age 45 years, defined as 3 or more of: high glycated hemoglobin; high waist circumference; high blood triglyceride; low high-density lipoprotein cholesterol; and high blood pressure. Reported television viewing time and metabolic syndrome data were available for 870 (87%) of 997 surviving participants. Mean television viewing time between ages 5 and 15 years was associated with metabolic syndrome at 45 years of age. This association persisted after adjusting for sex, socioeconomic status, and BMI at age 5 (odds ratio: 1.30; 95% confidence interval: 1.08 to 1.58; P = .006) and after further adjustment for adult television viewing (odds ratio: 1.26; 95% confidence interval: 1.03 to 1.54; P = .026). Childhood television viewing was also associated with lower cardiorespiratory fitness and higher BMI at 45 years of age. Time spent watching television during childhood and adolescence is associated with the risk of metabolic syndrome in mid-adulthood. Interventions to reduce screen time for children and young people may have long-lasting benefits for health.

The Longitudinal Association of Childhood and Adolescent Television Viewing with Substance Use Disorders and Disordered Gambling in Adulthood up to Age 45

Excessive leisure-time television viewing in childhood has been associated with a range of poorer outcomes in adulthood and may represent an early form of addictive disorder. As addictive disorders are often correlated, we tested the hypothesis that television viewing in childhood and adolescence would be longitudinally associated with adulthood substance-related and behavioural addictive disorders in a population-based cohort born in 1972/1973. Weekday television viewing time was reported at multiple ages from 5 to 15 years, and criteria for alcohol, cannabis, and tobacco use disorders and disordered gambling were assessed at multiple adult ages up to 45 years. Higher television viewing times were associated with a greater likelihood of meeting diagnostic criteria for all substance-related disorders and disordered gambling in models that were adjusted for sex (p values < 0.05). After adjustment for childhood socioeconomic status and childhood self-control, mean television viewing time (hours/day) remained associated with tobacco use disorder (OR = 1.22, 95% CI = 1.04–1.42, p = 0.017) and disordered gambling (OR = 1.33, 95% CI = 1.07–1.66, p = 0.010). Excessive, leisure-time television viewing in childhood and adolescence may be a modifiable risk factor for tobacco use disorder and/or disordered gambling in later life.

Anxiety And Depressive Symptoms Differ Between Levels Of Physical Activity And Screen Time Among Adolescents

The influence of physical activity (PA) and sedentary behaviours, especially screen time, on anxiety and depressive symptoms is comparatively less studied among adolescents. PURPOSE: Thus, this study quantified differences in anxiety and depressive symptoms between levels of PA and screen time among 1756 adolescents (14.8 ± 1.7y; 995 female) in secondary school in the Republic of Ireland. METHODS: Participants self-reported depressive (QIDS) and anxiety (STAI-Y2) symptoms, PA (PACE+), and average daily weekday/weekend hours of television (TV), computer and smartphone use. ANOVA with Bonferroni-corrected pairwise comparisons examined anxiety and depressive symptom differences between levels of PA and screen-time. Cohen’s d quantified the magnitude of differences. RESULTS: Anxiety and depressive symptoms significantly differed between PA levels (p ≤ 0.001), and weekday and weekend TV (p ≤ 0.001), computer use (p < 0.001), and smartphone use (p < 0.001). Results were materially the same when adjusted for age, gender, school type and residence (all p ≤ 0.001). Anxiety symptoms were greater for low compared to moderate (p < 0.001, d = 0.58) and high (p < 0.001, d = 0.87) PA, and for moderate compared to high PA (p < 0.001, d = 0.33). Depressive symptoms were greater for low compared to moderate (p < 0.001, d = 0.47) and high (p < 0.001, d = 0.67) PA, and for moderate compared to high PA (p < 0.001, d = 0.21). Compared to no TV, symptoms were lower for ≤2 h of weekday TV (anxiety: all p ≤ 0.004, d: 0.27-0.34; depressive: all p ≤ 0.01, d: 0.26-0.37) and ≤ 30 min/d of weekend TV (anxiety: p ≤ 0.007, d = 0.35; depressive: p ≤ 0.005, d = 0.36). For computer use, compared to lower use categories, symptoms were greater for ≥5 h/d of weekday (anxiety: all p ≤ 0.003, d: 0.53-0.79; depressive: all p < 0.001, d: 0.63-0.66) and weekend (anxiety: all p ≤ 0.02, d: 0.34-0.59; depressive: all p < 0.001, d: 0.43-0.72) use. For smartphone use, compared to lower use categories, symptoms were greater for ≥5 h/d of weekday (anxiety: all p ≤ 0.03, d: 0.31-0.70; depressive: all p ≤ 0.002, d: 0.34-0.74) and weekend (anxiety: all p ≤ 0.001, d: 0.34-0.76; depressive: all p < 0.001, d: 0.30-0.80) use. CONCLUSION: Anxiety and depressive symptoms differed based on PA and screen time behaviours. Dose-response and threshold effects were suggested for PA and screen time, respectively.

The association of adolescents’ television viewing with Body Mass Index percentile, food addiction, and addictive phone use

Television (TV) viewing remain a popular forms of screen time for adolescents. Greater TV viewing is associated with a number of negative consequences for adolescent health. In a changing media landscape, it is important to understand adolescents’ overall and commercial TV exposure, and how TV viewing is linked to health risks (e.g., obesity, food addiction, and phone addiction). The purpose of this study was to: 1) examine differences by age, gender, race/ethnicity, and parental education in overall TV and commercial TV viewing and 2) investigate whether adolescents who watch more overall TV and commercial TV programming were more likely to have a higher BMI percentile, more addictive eating, and more addictive phone use. A sample of 190 adolescents (13–16 years of age) completed Time-Use Diaries (TUDs) in 2015–2017. We found that girls had more overall weekday TV time than males. No other gender differences were detected for weekend TV time or commercial TV time. Higher BMI percentile was not correlated with greater overall or commercial TV viewing. However, we did identify a positive association between overall TV viewing and commercial TV viewing with addictive-eating and addictive phone use. This effect was mainly driven by boys. To our knowledge, this is the first study to investigate patterns of television viewing and addictive-like eating and addictive phone use. We conclude that adolescents, particularly boys, with higher TV viewing may be more likely to present with problems with addictive eating behavior and phone use. Our findings add to the research on the behavioral health correlates of TV viewing among adolescents.

Childhood and adolescent television viewing and internalising disorders in adulthood

Time spent watching television during childhood and adolescence has been linked to socio-emotional and physical health problems in adulthood. It is unclear whether excessive television viewing is a risk factor for internalising mental health disorders such as anxiety and depression. Longitudinal associations between television viewing in childhood and adult diagnoses of anxiety and depression were investigated in a population-based birth cohort from Dunedin, New Zealand. Mean weekday television viewing time was reported by parents and adolescents between ages 5 and 15 years (1977–1987). Diagnoses of any anxiety disorder and major depression were made using standard criteria from symptoms reported for the previous year at ages 18, 21, 26, 32, and 38 years (between 1990 and 2012). Analyses adjusted for sex, parent and teacher reports of worry/fearfulness at age 5, and socioeconomic status during childhood. Diagnoses were counted if present at any of these assessments. Approximately half of all participants met criteria for anxiety disorder or depression during at least one adult assessment. Participants who had watched more television during childhood and adolescence were more likely to have a diagnosis of anxiety in sex-adjusted analyses (OR [95% CI] 1.22 [1.05, 1.41], p = 0.01), although this association weakened after adjustment for early childhood worry/fearfulness and socioeconomic status. There was no association between television viewing and depression in sex- or fully-adjusted analyses. Excessive television viewing during childhood and adolescence may be a risk factor for developing an anxiety disorder in adulthood, but does not appear to influence the long-term risk for major depression.

Physical activity and food habits are associated with television time on weekends in Brazilian workers

Abstract Aims: Investigated the relation between eating habits or physical activity and weekend television viewing time, regardless of weekday television viewing in Brazilian workers. Methods: A representative cross-sectional study was conducted to measure the relation between weekend television viewing time and dietary indicators and physical activity across different domains in 47,477 workers. A questionnaire measured the time spent watching television per day on the weekend, physical activity indicators across different domains and eating habits. Absolute and relative frequencies and multinomial logistic regression adjusted were used to describe and identify the relationship between time spent watching television on the weekend and physical activity indicators or eating habits. Results: Workers who were physically active in the household (OR=1.09 [95%CI=1.04; 1.15] and OR=1.11 [95%CI=1.06; 1.16]) and leisure-time domains (OR=1.28 [95%CI=1.22; 1.35] and OR=1.30 [95%CI=1.24; 1.36]) were more likely to watch television ≥ 2 and ≥ 4 hours on a weekend day, respectively, than those watching television ≤ 1 hour/day. Consuming sweets (OR=1.30 [95%CI=1.22; 1.39]) and soft drinks (OR=1.11 [95%CI=1.03; 1.19]) was related to television watching ≥ 4 hours on a weekend day. However, workers who consumed fruits (OR=0.81 [95%CI=0.76; 0.85]) and vegetables (OR=0.91 [95%CI=0.86; 0.96]) daily were less likely to spend ≥ 4 hours watching television on a weekend day. Conclusion: We conclude that increased television viewing time on weekends, regardless of weekday television time, is related to leisure-time and household physical activity and with unhealthy eating habits in workers. Interventions focusing on the leisure-time may be an important alternative for health promotion in workplaces.

Tackling Youth Inactivity and Sedentary Behavior in an Entire Latin America City.

Real-world interventions are fundamental to bridge the research-practice gap in healthy lifestyle promotion. This study aimed to assess the impact of a 7-month, intensive, city-wide intervention (“Life of Health”) on tackling youth inactivity and sedentary behavior in an entire Latin-American city (Jaguariuna, Brazil). For youth, a program focused on tackling inactivity/sedentary behavior was delivered at every school (n = 18). Plausibility assessments (pre-to-post design) were performed with 3,592 youth (out of 8,300 individuals at school age in the city) to test the effectiveness of the intervention. Primary outcomes were physical activity and sedentary behavior. Secondary outcome was BMI z-score. Physical activity did not change (0; 95%CI:-2.7–2.8 min/day; p = 0.976), although physically inactive sub-group increased physical activity levels (11.2; 95%CI:8.8–13.6 min/day; p < 0.001). Weekday television and videogame time decreased, whereas computer time increased. Participants with overweight and obesity decreased BMI z-score (-0.08; 95%CI:-0.11−0.05; p < 0.001; −0.15; 95%CI:-0.19−0.11; p < 0.001). This intervention was not able to change the proportion of physical inactivity and sedentary behavior in youth at a city level. Nonetheless, physically inactive individuals increased PA levels and participants with overweight and obesity experienced a reduction in BMI z-score, evidencing the relevance of the intervention. Education-based lifestyle programs should be supplemented with environmental changes to better tackle inactivity/sedentary behavior in the real-world.

Exploring parents' screen-viewing behaviours and sedentary time in association with their attitudes toward their young child's screen-viewing.

Sedentary time and screen-viewing (SV) are associated with chronic disease risk in adults. Parent and child sedentary time and SV are associated. Parents influence children's SV through parenting styles and role modelling. Understanding whether parents' attitudes toward child SV are associated with their own SV and sedentary time will aid development of family interventions to reduce sedentary behaviours. Cross-sectional data with 809 parents from Bristol, UK were collected in 2012–2013 and analysed in 2016. Parental total sedentary time was derived from accelerometer data. Parents self-reported daily television viewing, use of computers, games consoles, and smartphone/tablets (none, 1–59 min, 1–2 h, > 2 h) and attitudes toward child SV. Adjusted linear and logistic regression models were used to examine associations, separately for weekdays and weekend days. Having negative attitudes toward child SV was associated with lower weekend sedentary time (Coeff: − 6.41 [95% CI: − 12.37 to − 0.45] min/day). Limiting behaviours and having negative attitudes toward child SV were associated with lower weekday television viewing (OR: 0.72 [0.57–0.90] and 0.57 [0.47–0.70] respectively), weekend television viewing (0.75 [0.59–0.95] and 0.61 [0.50–0.75]), and weekend computer use (0.73 [0.58–0.92] and 0.80 [0.66–0.97]). Negative attitudes were also associated with lower smartphone use on weekdays (0.70 [0.57–0.85]) and weekends (0.70 [0.58–0.86]). Parent self-efficacy for limiting child SV and setting SV rules were not associated with sedentary time or SV. Reporting negative attitudes toward child SV was associated with lower accelerometer-assessed weekend total sedentary time and self-reported SV behaviours, while limiting child SV was also associated with lower self-reported SV.

Parental control, nurturance, self-efficacy, and screen viewing among 5- to 6-year-old children: a cross-sectional mediation analysis to inform potential behavior change strategies.

Background: Children's screen viewing (SV) is associated with higher levels of childhood obesity. Many children exceed the American Academy of Pediatrics guideline of 2 hours of television (TV) per day. There is limited information about how parenting styles and parental self-efficacy to limit child screen time are associated with children's SV. This study examined whether parenting styles were associated with the SV of young children and whether any effects were mediated by parental self-efficacy to limit screen time.Methods: Data were from a cross-sectional survey conducted in 2013. Child and parent SV were reported by a parent, who also provided information about their parenting practices and self-efficacy to restrict SV. A four-step regression method examined whether parenting styles were associated with the SV of young children. Mediation by parental self-efficacy to limit screen time was examined using indirect effects.Results: On a weekday, 90% of children watched TV for <2 hours per day, decreasing to 55% for boys and 58% for girls at weekends. At the weekend, 75% of children used a personal computer at home, compared with 61% during the week. Self-reported parental control, but not nurturance, was associated with children's TV viewing. Parental self-efficacy to limit screen time was independently associated with child weekday TV viewing and mediated associations between parental control and SV.Conclusions: Parental control was associated with lower levels of SV among 5- to 6-year-old children. This association was partially mediated by parental self-efficacy to limit screen time. The development of strategies to increase parental self-efficacy to limit screen-time may be useful.

Association between childhood and adolescent television viewing and unemployment in adulthood

ObjectiveTo assess the long-term association between childhood television viewing and adult unemployment, and if this association is mediated by educational achievement. MethodStudy members were a general-population birth cohort of 1037 participants born in New Zealand in 1972/1973. Hours of weekday television viewing were reported at ages 5–15. Since age 18, unemployment was assessed retrospectively using life-history calendars to age 32. Information on educational qualifications was collected at age 32. ResultsChildhood and adolescent television viewing predicted adult unemployment. This association was significant for male Study members only (β=0.20, p<0.0001). The association for male Study members remained after further controlling for socioeconomic status, cognitive ability, and early indications of behaviour problems (p<0.0007). The association was only partially mediated by educational achievement and television viewing remained a predictor of unemployment after adjusting for this (p=0.0035). By logistic regression, each additional hour of daily television viewing was associated with an increased likelihood of spending at least 6months in unemployment between ages 18 and 32years (OR=1.36, 95%, CI=1.06, 1.76, p=0.0157). ConclusionChildhood and adolescent television viewing may have long-lasting consequences for adult unemployment for boys. This association is only partially explained by the association between television viewing and educational achievement.

Gender differences in sociodemographic and behavioral influences of physical activity in Mexican-origin adolescents.

Understanding the factors that contribute to physical activity (PA) in Mexican-origin adolescents is essential to the design of effective efforts to enhance PA participation in this population. Multivariable logistic regression was used to identify sociodemographic and behavioral correlates of self-reported PA in school and community settings in 1154 Mexican-origin adolescents aged 12-17 years in Houston, TX. The majority of adolescents were born in the US (74%), approximately half (51%) were overweight or obese, and nearly three-quarters (73%) watched more than 2 hours of weekday television. Similarities and differences by setting and gender were observed in the relationships between sociodemographic and behavioral characteristics and PA. In boys, parental education and attending physical education (PE) were positively associated with PA across multiple PA outcomes. Adolescent linguistic acculturation was inversely associated with participation in community sports, whereas parental linguistic acculturation was positively associated with PA at school. In girls, PA in school and community settings was inversely associated with TV viewing and positively associated with PE participation. These findings highlight similarities and differences in correlates of PA among boys and girls, and point toward potential sources of opportunities as well as disparities for PA behaviors in Mexican-origin adolescents.

The Editors’ Choice

The Editors’ Choice

Allergen exposure modifies the relation of sensitization to fraction of exhaled nitric oxide levels in children at risk for allergy and asthma

Studies on airway inflammation, measured as fraction of exhaled nitric oxide (FENO), have focused on its relation to control of asthma, but the contribution of allergen exposure to the increase in FENO levels is unknown. We evaluated (1) whether FENO levels were increased in children with allergic sensitization or asthma; (2) whether specific allergen exposure increased FENO levels in sensitized, but not unsensitized, children; and (3) whether sedentary behavior increased FENO levels independent of allergen exposures. At age 12 years, in a birth cohort of children with a parental history of allergy or asthma, we measured bed dust allergen (dust mite, cat, and cockroach) by means of ELISA, specific allergic sensitization primarily based on specific IgE levels, and respiratory disease (current asthma, rhinitis, and wheeze) and hours of television viewing/video game playing by means of questionnaire. Children performed spirometric maneuvers before and after bronchodilator responses and had FENO levels measured by using electrochemical detection methods (NIOX MINO). FENO levels were increased in children with current asthma (32.2 ppb), wheeze (27.0 ppb), or rhinitis (23.2 ppb) compared with subjects without these respective symptoms/diagnoses (16.4-16.6 ppb, P < .005 for all comparisons). Allergic sensitization to indoor allergens (cat, dog, and dust mite) predicted higher FENO levels and explained one third of the variability in FENO levels. FENO levels were highest in children both sensitized and exposed to dust mite. Greater than 10 hours of weekday television viewing was associated with a 0.64-log increase in FENO levels after controlling for indoor allergen exposure, body mass index, and allergic sensitization. Allergen exposures and sedentary behavior (television viewing/video game playing) might increase airway inflammation, which was measured as the FENO.

Parental influences on television watching among children living on the Texas–Mexico border

PurposeWe examined the association of parental television (TV) rules and compliance with the American Academy of Pediatrics' (AAP) recommendations of ≤2h of television per day in a primarily Hispanic sample of elementary school children (n=734) living on the U.S. side of the Texas–Mexico border. The potential modifying effects of children's home environment (parental TV watching, parent at home after school, and TV in bedroom) were also examined. MethodsA cross-sectional analysis was performed on baseline survey data merged from two waves (2006 and 2007) of a CDC-funded TV reduction intervention with 4th grade children (mean age: 9.5years). Logistic regression analyses were conducted to examine associations. ResultsChildren who had TV rules were 1.4 (95% CI: 1.04, 1.94) and 1.7 (95% CI: 1.22, 2.32) times more likely to meet the AAP recommendation for weekend and weekday TV watching, respectively. Parental TV watching and TV in bedroom modified the effect of TV rules on children's TV watching, with null associations found for children whose parents watch TV frequently and for children with no TV in bedroom. No interaction effect was found for children's afterschool context. ConclusionsParental TV limits is one strategy for reducing children's television watching that merits further investigation.

Identifying ‘unhealthy’ food advertising on television: a case study applying the UK Nutrient Profile model

To evaluate the feasibility of the UK Nutrient Profile (NP) model for identifying 'unhealthy' food advertisements using a case study of New Zealand television advertisements. Four weeks of weekday television from 15.30 hours to 18.30 hours was videotaped from a state-owned (free-to-air) television channel popular with children. Food advertisements were identified and their nutritional information collected in accordance with the requirements of the NP model. Nutrient information was obtained from a variety of sources including food labels, company websites and a national nutritional database. From the 60 h sample of weekday afternoon television, there were 1893 advertisements, of which 483 were for food products or retailers. After applying the NP model, 66 % of these were classified as advertising high-fat, high-salt and high-sugar (HFSS) foods; 28 % were classified as advertising non-HFSS foods; and the remaining 2 % were unclassifiable. More than half (53 %) of the HFSS food advertisements were for 'mixed meal' items promoted by major fast-food franchises. The advertising of non-HFSS food was sparse, covering a narrow range of food groups, with no advertisements for fresh fruit or vegetables. Despite the NP model having some design limitations in classifying real-world televised food advertisements, it was easily applied to this sample and could clearly identify HFSS products. Policy makers who do not wish to completely restrict food advertising to children outright should consider using this NP model for regulating food advertising.

Programming Obesity and Poor Fitness: The Long‐term Impact of Childhood Television

To assess whether the long-term effects of childhood television viewing on BMI and cardiorespiratory fitness are mediated by adult viewing. This prospective study included an unselected birth cohort of 1,037 participants (535 men) born in Dunedin, New Zealand in 1972/1973. Hours of television viewing on weekdays were reported at ages 5, 7, 9, 11, 13, 15, and 32 years. BMI and cardiorespiratory fitness were measured at age 32 years. Both childhood and adult television viewing times were significantly associated with higher BMI and lower cardiorespiratory fitness at age 32 years. Childhood television viewing was a better predictor of adult BMI and fitness than adult viewing and remained a significant predictor of these outcomes after adjusting for adult viewing time. After adjusting for adult viewing, the odds (95% confidence interval) of adult obesity increased by a factor of 1.25 (1.01, 1.53) and poor fitness increased by a factor of 1.40 (1.16, 1.70) for each hour of mean weekday television viewing during childhood. The association between childhood television viewing and obesity and poor fitness in adulthood is not mediated by adult viewing. The detrimental health effects of watching too much television during childhood persist into adulthood. Attempts to reduce adult obesity and poor fitness by modifying television viewing habits need to begin in childhood.

Association Between Television, Movie, and Video Game Exposure and School Performance

The relationship between media exposure and school performance has not been studied extensively in adolescents. The purpose of this work was to test the relative effects of television, movie, and video game screen time and content on adolescent school performance. We conducted a population-based cross-sectional survey of middle school students (grades 5-8) in the Northeastern United States. We looked at weekday television and video game screen time, weekend television and video game screen time, cable movie channel availability, parental R-rated movie restriction, and television content restriction. The main outcome was self-report of school performance (excellent, good, average, or below average). We used ordinal logistic-regression analysis to test the independent effects of each variable, adjusting for demographics, child personality, and parenting style. There were 4508 students who participated in the study; gender was equally represented, and 95% were white. In multivariate analyses, after adjusting for other covariates, the odds of poorer school performance increased with increasing weekday television screen time and cable movie channel availability and decreased with parental restriction of television content restriction. As compared with children whose parents never allowed them to watch R-rated movies, children who watched R-rated movies once in a while, sometimes, or all of the time had significantly increased cumulative odds of poorer school performance. Weekend screen time and video game use were not associated with school performance. We found that both content exposure and screen time had independent detrimental associations with school performance. These findings support parental enforcement of American Academy of Pediatrics guidelines for media time (particularly weekdays) and content limits to enhance school success.

Racial/Ethnic and Socioeconomic Status Differences in Overweight and Health-Related Behaviors among American Students: National Trends 1986–2003

Purpose This article reports long-term trends by race/ethnicity and socioeconomic status (SES) in the percent of American students who are overweight and who engage in three health-related behaviors hypothesized to be associated with overweight. Methods Data are from the Monitoring the Future annual surveys, using nationally representative samples of eighth, 10th, and 12th grade students. Participants include 62,156 eighth and 64,899 10th graders who completed the 1993–2003 surveys and 35,107 12th graders who completed the questionnaire form containing the measures pertaining to this study in the 1986–2003 surveys. Trends are presented separately by gender and grade level for different racial/ethnic and SES subgroups, in: (a) percent overweight (body mass index ≥ 85th percentile), (b) percent who always or almost always eat breakfast, (c) percent who regularly exercise vigorously, and (d) average hours of weekday television viewing. Results The prevalence of overweight and of engaging in less healthy behaviors is considerably greater among youth from racial/ethnic minority backgrounds, of lower socioeconomic status, and in higher grades. Trends in overweight and these behaviors are found to vary substantially by gender, racial/ethnic group, socioeconomic status, and grade level. Conclusions The study findings show well-established and persistent differences in the percent of racial/ethnic minority and low SES youth who are overweight and whose dietary and exercise habits are less healthy. Documentation of these problems may lead to research and policy agendas that will contribute both to our understanding and to the reduction of these important health disparities.

Effects of the SMART Classroom Curriculum to Reduce Child and Family Screen Time

Evidence for adverse effects of screen media exposure has led to recommendations to limit children's screen time. This paper describes a randomized controlled trial of SMART (Student Media Awareness to Reduce Television), an 18-lesson, theory-based classroom curriculum to reduce screen time among third and fourth grade children in two matched public elementary schools (n = 181). Intervention school children significantly reduced their weekday television viewing and weekday and Saturday video game playing compared to controls. Greater effects were found among boys and more adult-supervised children. Mothers, fathers, and siblings and other children in intervention school households also reduced their television viewing. The findings demonstrate the efficacy of a classroom intervention to reduce screen time among elementary school children and their family/household members.

Watching television is associated with childhood obesity: but is it clinically important?

To assess the impact of television viewing during childhood and adolescence on body mass index (BMI) in children up to the age of 15 years. Unselected birth cohort, assessed at birth and every 2 years from age 3 to 15 years. In all, 1037 individuals were assessed at age 3 years. At age 15 years, 976 (95% of living cohort) continued to participate. Parental estimates of weekday television viewing between age 5 and 11 years. Self-reports of television viewing at age 13 and 15 years. Weight and height were measured at each age to calculate BMI. BMI and prevalence of overweight at all ages were significantly associated with mean hours of television viewing reported in the assessments up to that age. These associations were stronger in girls than boys. The associations remained significant after adjusting for parental body mass indices and socio-economic status. Time spent watching television is a significant predictor of BMI and overweight in childhood. Although the effect size appears small, it is larger than the effect sizes commonly reported for nutritional intake and physical activity. Television viewing should be regarded as an important contributing factor to childhood obesity.