Drs. R.M. Viner and T.J. Cole from the University College London evaluated the effects of early childhood television watching on adult obesity by assessing data from 8,158 participants of the 1970 Birth Cohort. Height, weight, and frequency of television watching were assessed at ages 5, 10, and 30 years. At age 5, approximately 40% of the participants exceeded the AAP's guidelines, although the average number of hours watched was 1 ½ hours. The researchers found that each additional hour of weekend TV watching by five-year-old children over the AAP's suggested two hours may increase the risk of obesity in 30 year olds by 7%.
Drs. Kirsten Davison, Lori Francis, and Leann Birch from the State University of New York evaluated the television viewing behaviors of 173 girls and their parents. At both 9 and 11 years old, the girls watched an average of 1.9 hours of television a day, although approximately 39% of girls and 30% of parents exceeded the AAP's guidelines. Parents who relied heavily on television viewing as a recreational activity reported higher levels of television watching with their daughters. Girls who were exposed to two or more parenting risk factors for increased television viewing, such as the lack of parental limitations on their television watching and their parents' own television viewing habits, were five to ten times more likely to exceed the AAP's guidelines at both 9 and 11 years old. Girls who watched more than the recommended two hours per day were 2.6 times more likely to be overweight than girls who watched less than two hours.
Limiting the amount of time a child spends in front of the television (for example, removing televisions from children's bedrooms) may be a good way for parents to reduce the risk of obesity in children. Because parents' television viewing habits directly influences their children's, parents must serve as role models. Parents should limit the frequency of television viewing by encouraging alternate forms of recreation and selective program choices for themselves and their children. The TV Turnoff Network (www.tvturnoff.org) offers additional guidance for parents and children who want to spend more time away from the television. Although the increase in childhood obesity is not caused solely by television watching, Dr. Reginald Washington points out in the editorial that accompanies the articles, "Society, as a whole, must realize that to effectively control and prevent this obesity epidemic, all risk factors must simultaneously be reduced."
The studies are reported in "Links between parents' and girls' television viewing behaviors: A longitudinal study" by Kirsten K. Davison, PhD, Lori A. Francis, PhD, and Leann L. Birch, PhD, "Television viewing in early childhood predicts adult body mass index" by R.M. Viner M.D., Ph.D. and T.J. Cole Ph.D., and the editorial "One way to decrease an obesogenic environment" by Reginald Washington, MD. The article appears in The Journal of Pediatrics, Volume 147, Number 4 (October 2005), published by Elsevier.