Abstract

Adolescents spend almost nine hours a day engaging with media. As a result, they are confronted with large amounts of obesogenic content that shapes their understanding of what are normal and acceptable eating behaviors. Utilizing primary data collected from a sample of 4,838 low-income, racially and ethnically diverse middle school students in Los Angeles County, I studied the effects of different types of media use on dietary patterns and weight outcomes. I assessed whether those effects were mediated by individual-level health behaviors ; and whether it was possible to buffer the deleterious effects of media consumption on eating behaviors by associating with friends who are perceived to place importance on eating healthfully, friends who are perceived to be dieters, or by having classmates who eat more healthfully, or by having classmates who are on average slim. I also examined social media specifically and assessed whether the effects on dietary behaviors were exacerbated for individuals who perceive themselves to be overweight or are trying to lose weight. In this way, I was able to gain a clearer picture of the social and environmental determinants of obesity risk in adolescents.I found that media consumption is consequential to the diet of middle school students. This was a robust finding. Independent of health behaviors, friends, classmates, weight status, and dieting behaviors, media consumption was associated with poor eating outcomes. Media consumption generally results in greater consumption of sugar-sweetened beverages, junk food and fast food and less consumption of fruits and vegetables. Strong support emerged that snacking on junk food while consuming media complements other unhealthful eating behaviors. There was relatively weak evidence that sleep duration or physical activity explained the relationship between media consumption and eating behaviors. Furthermore, I looked at contextual factors and showed that friend and classmate behaviors matter independent of media consumption. That is, one’s social networks contribute to poor dietary behaviors. Finally, I examined social media use specifically and found that it was associated with poor dietary behaviors for both males and females. There was also weak evidence to suggest dieting buffers the deleterious effects of social media on eating behaviors for males. But more importantly, weight-related concerns and weight control behaviors served to restrain consumption of excess discretionary calories that come from things like sugar-sweetened beverages, junk food and fast food independent of social media consumption.Understanding and addressing determinants of eating behaviors is of critical importance. In a complex society where youth are confronted with obesogenic content in media, peer influences, and other socio-ecological factors, it is no wonder that obesity among young people is a complex and difficult issue to address. It will not be until more multi-level and well-informed public health efforts are implemented that any real change can be made in the eating behaviors and health outcomes of our youth. If this does not happen, it is unlikely that we will be able to halt or reverse the obesity epidemic among youth.