Children’s health widely affected by TV, computers, video games

Media may have long-term effects on children’s social, psychological and physical health.

Although the influence of television and other media on children is often a talking point for politicians, clinical research of the topic has been somewhat lacking. Many studies on the subject are dated and do not consider the changing role that various forms of media play in modern society and their effect on the health of children and adolescents.

The Archives of Pediatrics and Adolescent Medicine recently devoted an entire issue to clinical studies that examine various health effects of media on pediatric patients. The studies focused on several forms of media – including television, computers and video games – and were published together to draw increased attention to the escalating health issues associated with the increasing influence of media on children and the long-term effects that may result.

“Media need to be recognized as a major public health issue rather than as a series of commercial endeavors in need of regulation, as they are among the most profound influences on children in this country; this intersects with many other issues that are critically important to child health, including violence, obesity, tobacco and alcohol use, and risky sexual behaviors,” Dimitri A. Christakis, MD, from the Child Health Institute at the University of Washington in Seattle, wrote in an editorial that accompanied the studies in the Archives of Pediatrics and Adolescent Medicine.

Donald Shifrin, MD, chair of the Committee on Communications at the American Academy of Pediatrics, agreed that it was important to recognize the public health issues associated with media. “It is about time we validate this research on the behavioral, cognitive, social, and physical outcomes of media exposure rather than wait for more evidence of possible adverse effects,” Shifrin wrote in a separate accompanying editorial. “Increased awareness by physicians, ongoing innovative research beginning at earlier ages, and soliciting active partnerships to teach media literacy should allow us to protect our most precious resource.”

Television and overweight

Excessive exposure to television is a risk factor for overweight in preschool-aged children, according to a study by researchers at the University of Michigan. The association between total television exposure and the risk of overweight was examined in 1,016 children, selected randomly from 10 centers in the United States. The children were examined at 36 months and again at 54 months.

The study’s researchers, led by Julie Lumeng, MD, from the Center for Human Growth and Development at the University of Michigan, defined exposure to television as “being awake in the room with the television on for two hours or more per day.” Children were considered overweight if they had a BMI >95th percentile for age and gender.

According to parental reporting, 31.7% of children were exposed to 2 or more hours of television per day; 68.3% were exposed to <2 hours of television per day. At 36 months, 5.8% of the children were overweight; by 54 months, this figure had increased to 10%. An average exposure to two or more hours of television per day was associated with a risk of overweight at 36 months that was 2.92 times higher than in children who were exposed to less than two hours of TV per day and risk of overweight at age 54 months that was 1.71 times higher.

The results were adjusted for a variety of factors, including gender, race, behavioral problems and hours per week in nonparental care; maternal marital status, education, age and depressive symptoms; family income-needs ratio; and exposure to educational television. Only adjustments for maternal age altered the results, and the effects of television exposure were significant even after adjusting for these other factors.

Lumeng told Endocrine Today that television viewing may be a more significant risk than most other factors in the home. “There appears to be something about the television that increases overweight risk independent of all of these other markers of stress at home or quality of the home environment,” she said. “The two primary possibilities are that television reduces physical activity, and secondly, that it increases exposure to television commercials that powerfully shape children’s food preferences.”

Lumeng also said that she expects the results would be similar for other patient populations as well. “Prior studies have shown that excessive television viewing increases the risk of overweight or obesity in older children and adults,” she said.

Source: Lumeng J., et al.

Television’s influence on diet

Increased television viewing is associated with increased caloric intake, according to a study by researchers at Harvard. The researchers examined the effects of television viewing on dietary habits in 548 Boston-area children.

The average age of children in the study was 11.7 years at baseline. Study participants were followed for two years. Diet, physical activity and television viewing were measured.

After adjustments for several covariates, the results demonstrated that each increase of one hour in daily television viewing was associated with an average additional 167 kcal/day. The results also showed a correlation between increased television viewing and an increased consumption of foods commonly advertised on television, which are typically calorie-dense and low-nutrient foods.

“Although children and youth are encouraged to watch what they eat, many youth seem to eat what they watch, and in the process increase their risk for increasing their energy intake,” the researchers wrote. “In the absence of regulations restricting food advertising aimed at children, reduction in television viewing is a promising approach to reducing excess energy intake.”

Influence of parents’ weight

Parental BMI may have an effect on the association between children’s diet and television viewing. Researchers from the University of Texas at Austin found that when parental obesity is taken into account, the amount of television viewing does not significantly relate to an increased risk for childhood overweight. Furthermore, the researchers said that parental BMI may serve to moderate the relationship between television viewing and child weight status in adolescents, but this association was not seen among younger children.

For this study, the researchers conducted in-home or telephone interviews of 1,483 children aged 6 to 19 and their parents. The children were grouped into one of three weight categories: normal weight, at risk for overweight or overweight. These categories were defined by current Centers for Disease Control and Prevention standards. Parents were also measured for BMI and grouped according to CDC standards.

The results demonstrated that parental obesity increased the risk of child overweight for all children except the subgroup of boys aged 6 to 9. There were significant interactions between television viewing hours and parental obesity among boys aged 14 to 19 years and girls aged 10 to 13. For these groups, the odds of overweight status increased with viewing hours for children with at least one obese parent. However, there was no increase for children with normal-weight parents.

Advertising messages

Nutritional messages are often lacking in television advertising, according to researchers at the University of Minnesota in Minneapolis. The researchers noted that this is particularly problematic among television shows geared toward black children. The researchers specifically examined television shows with a high number of young black viewers because this patient population has a significantly higher risk for overweight.

The researchers examined television advertising from 3 pm to 9 pm over the course of one week on three stations: Black Entertainment Television, the WB and Disney Channel. A total of 1,098 advertisements were seen on these channels during this time; 256 of these ads were for foods and/or beverages. Of the food and beverage commercials, 36.3% were for fast food restaurants, 31.3% were for drinks, 16.8% were for candy, 13.7% were for cereals and 2% were for snacks. About 70% of the food and beverages commercials were repeated throughout the day and week.

Compared with the other channels, BET had significantly more food and beverage advertisements. More than 63% of the total food and beverage commercials aired on BET; 32.4% aired on the WB and 4.3% aired on the Disney Channel. The researchers noted that most of the food and beverages advertised do not meet the health recommendations set by the federal government. Furthermore, the ads rarely depicted health-related messages or physical activity.

“This study supports previous findings that suggest African-American television shows have a disproportionate number of unhealthy food images and may influence the eating behavior and knowledge of vulnerable African-American children,” the researchers wrote.

Source: Outley CW, et. al.

Peer pressure?

An adolescent’s social interactions at school may be a strong factor in determining the specific programs and the total amount of television watched, according to researchers at the University of Wisconsin-Madison.

For this study, the researchers recruited a cohort of 4,532 students in grades seven through 12 at 132 American public and private schools who participated in the National Longitudinal Study of Adolescent Health. The participants were asked about the number of hours of television they viewed each week, as well as the amount of television and programs viewed by their friends and peers.

The results indicated that the number of hours of television that adolescents report viewing per week was associated with their peers’ reported hours of television viewing. After making adjustments for various factors, the researchers concluded that a one-hour increase in average television viewing at the school level was associated with an increase in about 30 minutes of television viewing in each adolescent.

The researchers said these findings are important because they underscore the influence of peer pressure on adolescents’ media habits. “This finding is important for both future attempts at modeling the determinants of adolescent television viewing and suggestions for future policy interventions,” the researchers wrote. “In reducing the number of hours of television watched, these interventions could also positively affect adolescent obesity, emotional problems, and academic achievement.”

Social isolation

Increased viewing of certain kinds of television programs may be associated with reduced peer interaction. Researchers at the Children’s Hospital Boston and Harvard Medical School found that children who spent more time viewing violent television programs spent less time with friends.

The study included data from 1,356 children aged 6 to 12. The researchers examined study participants’ habits of watching both violent and nonviolent television alone or with friends.

The results demonstrated that viewing violent television programs alone was negatively correlated to time spent with friends. Among children aged 6 to 8, an additional one hour of violent television viewing was associated with about 20 minutes less time spent with friends. For children aged 9 to 12, an additional one hour of violent television was associated with 25 minutes less time spent with friends. However, similar associations were not seen for nonviolent television programs. The researchers recommended children’s exposure to violent television programs should be limited in an effort to promote optimal social development and mental health.

The results also showed that children who viewed television programs with friends were more likely to spend time with friends participating in other nontelevision activities. For children aged 6 to 8, one additional hour of watching television with friends corresponded to 59 more minutes of time spent with friends participating in nontelevision activities. For children aged 9 to 12, each hour spent watching television with friends was associated with about 62 more minutes of time spent with friends participating in nontelevision activities.

Parental restrictions

Many parents implement rules to restrict their children’s access to forms of media, according to a survey by researchers at Wake Forest University Baptist Medical Center in Winston-Salem, N.C. The researchers said that previous studies have indicated that a high percentage of children use some form of media more than two hours a day; this study was designed to examine parents’ role in determining the number of hours per day children had access to media.

The researchers gave questionnaires to 1,831 parents who had children under the age of 11 and who came to a clinic with their child for a well visit. The questionnaires asked about children’s media habits and parents’ rules regarding media access.

About half of the parents said they had a single approach for limiting their children’s access to media. Twenty-three percent of the parents said they placed time restrictions on children’s access to media; 11% said they practiced instructive mediation, where they discussed media with their children. Seven percent of parents said they allowed their children unlimited access to media and 59% said they used multiple strategies in controlling their children’s access to media.

The researchers said children whose parents used restrictive or instructive approaches were more likely to have an increased awareness about the potential negative effects of media. In contrast, a decreased awareness of this was seen among children whose parents allowed them unlimited access to media.

Video games’ effect on health

Video games may be less harmful than television viewing. However, video-game playing at home should not be considered a substitute for physical activity.

A study by researchers at the University of Miami examined the metabolic and physiologic responses to video game playing in 21 boys between the ages of 7 and 10. Participants played a video game for 15 minutes. Blood pressure was monitored before and during game play; blood glucose and lactate levels were measured before and immediately after game play.

The results showed significant increases for several metabolic and physiologic factors. The average increase was 18.8% for heart rate, 22.3% for systolic blood pressure, 5.8% for diastolic blood pressure, 51.9% for ventilation, 54.8% for respiratory rate, 49% for oxygen consumption, and 52.9% for energy expenditure. No significant changes were seen for lactate or glucose levels.

Arlette Perry, PhD, from the exercise and sport sciences department at the University of Miami, told Endocrine Today that the results indicated that video-game playing should not be grouped with television in studies of sedentary activities because it results in increases in various metabolic and physiologic variables in young children.

Perry said the increases seen during video-game playing were equivalent to walking at a pace of about 3 MPH. However, Perry noted that oxygen consumption was significantly lower during video-game playing than it was during physical activity. Furthermore, the changes were below those outlined in national health recommendations.

Perry stressed that video-game play should not be considered a substitute for regular physical activities. “For children who watch an excessive amount of television, video-game playing may be a slight improvement and can be useful as a transition toward more physical activity,” Perry said. “I only recommend video games as a temporary tool to help sedentary children transition toward more exercise. But the ultimate goal is to get these kids outside and to help them achieve greater levels of physical activity.”

Source: Wang X, et. al.

Violent video games

Video games rated “M” (for mature) may be exposing children to a variety of messages that could potentially have a negative influence on their perceptions, attitudes and behaviors. A study from Harvard School of Public Health found that many M-rated video games are more adult-oriented than parents and doctors often realize.

To examine this issue, the Harvard researchers created a database of M-rated video game titles. From this, the researchers selected a random sample and recorded at least one hour of game play from each game in the sample. The researchers then assessed the content, performed statistical analyses to describe the content and compared the results with the Entertainment Software Rating Board content descriptors for each game. The content was analyzed for depictions of violence, blood, sexual themes, gambling, alcohol, tobacco, drugs and profanity.

The researchers said the Entertainment Software Rating Board content descriptors for violence and blood were usually an accurate indication of such content in the video games. However, labels were lacking for many other aspects of the game. The researchers observed content in 81% of the games that lacked a content descriptor but could have warranted one. “M-rated video games are significantly more likely to contain blood, profanity and substances; depict more severe injuries to human and nonhuman characters; and have a higher rate of human deaths than video games rated T [for ‘teen’],” the researchers wrote.

Media violence and health

Exposure to violent forms of media may be associated with the development of negative attitudes and behaviors related to health, according to a study at the University of California, San Francisco.

The researchers recruited 100 male college students who were aged 18 to 21. The cohort included students who grew up in violent homes and/or communities, as well as those who grew up in more peaceful environments. The students were randomly assigned to play one of two video games: The Simpsons: Hit and Run (low violent content) or Grand Theft Auto III (high violent content). The two groups were matched for lifetime violence exposure and race.

The participants were studied for various consequences of the video games, including effects on blood pressure, hostile social information processing, uncooperative behavior, and attitudes toward health risk behaviors, such as violence, alcohol use, marijuana use and sexual activity without use of a condom.

All participants watched a relaxing video about Hawaii for 10 minutes before playing the video game for 10 minutes. The researchers measured blood pressure four times during the Hawaii video and four times during video game playing. At the completion of video game play, participants completed an effect checklist and a measure of attitudes toward harmful health behaviors and violence.

The results showed that participants who were assigned to play the more violent video game showed greater increases in diastolic blood pressure between the rest period and game play. Compared with those who played the less violent video game, the participants who played the more violent video game were more likely to show greater negative affect and have more permissive attitudes toward using alcohol and marijuana, and more uncooperative behavior.

Systolic blood pressure was elevated during the violent game only by those who had a history of exposure to violence.

Effects on sexual initiation

Adolescents who watch excessive television or experience little parental regulation over television viewing may be more likely to initiate sexual intercourse earlier, according to research from the University of Wisconsin School of Medicine and Public Health in Madison.

The researchers interviewed 4,808 adolescents under the age of 16. All included adolescents had not engaged in sexual intercourse at the time of the baseline interview. At the baseline interview, the students were asked to calculate the average number of hours of television they watched per day and about parental regulations regarding television viewing. Less than two hours of television each day was considered “low use” and >2 hours was considered “high use.” At the baseline interview, 48.8% of students watched at least two hours of television.

The students underwent a similar interview one year after the baseline interview. At this time, 15.6% of the students had initiated intercourse. Students who watched more than two hours of television per day and/or lacked parental regulation of television use were 1.35 times more likely to initiate sexual intercourse by the one-year follow-up interview.

When asked about their parent’s view of sex, 73.8% of the students noted “strong parental disapproval of sex.” Of this subgroup, 12.5% had initiated sexual intercourse at the one-year period. The risk of sexual initiation among this subgroup was independently associated with high television use and a lack of parental regulation of television viewing. Among adolescents who did not report strong parental disapproval of sex, the rate of sexual initiation was 24.1%. The researchers said this rate was unrelated to television use.

“The American Academy of Pediatrics recommends that children and adolescents view television no more than two hours each day and that parents take an active role in guiding television use,” the researchers wrote. “Although there is limited evidence about the effectiveness of these recommendations, our results suggest that successful implementation of these guidelines may diminish the risk of early sexual initiation by young adolescents.”

For more information:

• Archives of Pediatrics and Adolescent Medicine. 2006;160.