Ethnic and Gender Differences in the Relationships between Television Viewing and Obesity, Physical Activity, and Dietary Fat Intake

Abstract

There has been speculation that TV viewing is one of the most easily modifiable causes of obesity. However, studies examining the relationship between television viewing and obesity in children and adolescents have consistently found only weak, if any, association. In a sample of 1,912 ninth graders, we looked for evidence of ethnic and gender differences in the relationships between TV viewing and adiposity, physical activity, and dietary fat intake that may explain the weak overall associations found in other samples. The sample was 47.2 percent female and 52.7 percent male, 34.7 percent Latino/Hispanic, 27.9 percent Asian/Pacific Islander, 22.0 percent white, 6.8 percent African American, 1.7 percent Native American/Alaska Native, 2.0 percent Other, and 4.8 percent who reported they belonged to more than one ethnic group. Self-reports of TV viewing, physical activity, and dietary fat intake and measurements of height and weight all had high test-retest reliabilities. Boys reported more TV viewing than girls, except among African Americans, with African American girls reporting more TV viewing than any other group. Boys also reported being more physically active and eating more high-fat foods than girls. Among both boys and girls, African Americans reported watching significantly more TV, being more physically active, and eating more fatty foods than the other ethnic subsamples. Whites reported the least TV viewing. African Americans and Latino/Hispanics had the greatest body mass indexes (BMI), and whites had significantly greater BMIs than Asian/Pacific Islanders. Weekly hours of TV viewing was only weakly associated with BMI. The only statistically significant association between TV viewing and BMI was among white boys. TV viewing was also only weakly associated with physical activity. Though most correlations were negative, none was statistically significant. Total weekly hours of TV viewing was significantly associated with dietary fat intake in the entire sample and among both boys and girls. In the ethnic subsamples, the associations were statistically significant for Latino/Hispanic boys and girls, Asian/Pacific Islander girls, and white boys and of borderline statistical significance among the smaller sample of African American boys. Overall, the findings suggest that TV viewing is associated with increased dietary fat intake. These results do not support the proposal that TV viewing is an important cause of adolescent obesity or decreased physical activity. The findings of gender and ethnic subsample-specific associations suggest that cultural factors may influence the susceptibilities of children and adolescents to the effects of television viewing.