Approximately 11 million U.S. children and adolescents are overweight or obese, and evidence suggests a correlation between television viewing and adolescent weight gain. Some research has suggested a connection between weight gain and the mere presence of a television in a child's bedroom. To evaluate this relationship, researchers conducted four years of telephone surveys of U.S. children ages 10 to 14 years. The study included 6,522 adolescents initially (mean age, 12 years; 52% were male), 4,575 at two years, and 3,055 at the four-year follow-up.
At baseline, 59% of participants reported having a television in their bedroom. Bedroom televisions were 8% more prevalent among boys than among girls and 16% more prevalent among blacks and Hispanics than among whites and other races. They grew steadily more common as levels of income and parental education decreased. In addition, children with bedroom televisions reported having less-demanding and less-responsive parents, as well as greater exposure to television, movies, and video games on weekdays, compared with adolescents without bedroom TVs. There was a moderate linear relationship between bedroom televisions and hours spent watching television or playing video games and the number of movies watched weekly.
The mean body mass index (BMI) at years 2 and 4 among children with bedroom televisions had increased by 1.16 and 1.31, respectively. After adjustment for a number of variables, such as viewing time and parental responsiveness, this association remained but decreased to 0.57 at year 2 and 0.75 at year 4. In addition, every hour of television watching per week was independently associated with an average BMI increase of 0.14 from years 2 to 4.
The authors suggest that the increase in adiposity seen in children who had a television in the bedroom may be linked to disruption of sleep patterns, greater exposure to food advertising, or uncaptured effects of viewing time. They argue that removing bedroom televisions might aid in curbing the childhood obesity trend.
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