BALTIMORE, MARYLAND. Obesity is reaching epidemic proportions in the United States. In just 12 years the proportion of obese adults has risen from 25 per cent to 33 per cent and similar increases have been observed among children and adolescents. The prevalence of obesity has doubled in England in the past decade despite the fact that daily fat and energy intake have shown a significant decrease. Researchers at the Johns Hopkins University School of Medicine believe the main reason for the obesity epidemic is a lack of physical activity and an increase in sedentary activites, notably television viewing. They have just issued a report covering a study of 4063 children aged eight through sixteen years. The physical activity level and television viewing habits of the children were determined and compared to their body weight and degree of fatness. The researchers found that 85 per cent of boys and 74 per cent of girls participated in vigorous play or exercise three or more times per week. They also found that 26 per cent of all American children watch four or more hours of television per day. The rate was highest among black children where 43 per cent of boys and girls reported watching television for four or more hours per day leaving little time for physical activities. The researchers conclude that watching television for four or more hours per day is significantly related to obesity. Surprisingly, the level of physical activity showed no significant correlation with indicators of obesity (body mass index and amount of body fat). The researchers speculate that lack of physical activity and increasing television viewing in the home may be linked to concerns about crime. A recent survey of parents in the United States concluded that 46 per cent of them believed that their neighbourhoods were unsafe. The researchers recommend that priority be given to developing strategies for increasing physical activity and decreasing sedentary activities such as television viewing, computer games, etc. among children. This is particularly urgent in view of the fact that being obese as a child increases the risk of developing health problems as an adult. Dr. Thomas Robinson in an accompanying editorial speculates that the link between television viewing and obesity may be due to the fact that television viewing reduces the time available for physical activity. He also points out that there is evidence that the eating habits of children and adolescents are influenced by television advertising and that frequent television viewers tend to eat higher fat diets.
Andersen, Ross E., et al. Relationship of physical activity and television watching with body weight and level of fatness among children. Journal of the American Medical Association, Vol. 279, March 25, 1998, pp. 938-42
Robinson, Thomas N. Does television cause childhood obesity? Journal of the American Medical Association, Vol. 279, March 25, 1998, pp. 959-60 (editorial)