Challenging Dogma - Spring 2008

...Using social sciences to improve the practice of public health

Friday, April 18, 2008

Adolescent Obesity Interventions Fail to Think Outside of the Lunchbox—Reaching School-Aged Students May Be More Complex Than We Thought – Jessica Ten

In the United States, the prevalence of overweight adolescents has been climbing. Being overweight affects youths across state lines, cultural differences and socioeconomic groups. Data from the 2005 Youth Risk Behavior Surveillance (YRBS) show that 15.7% of students are at risk for becoming overweight and 13.1% are overweight (1). Cross-sectional surveys like YRBS have shown that the prevalence of overweight has not leveled off or decreased within the last few decades, but has increased to even higher levels.
There are complex causes and outcomes of overweight and obesity among youth. Weight gain is caused by an imbalance of energy intake compared to energy expended (in other words, consuming more calories than the body uses), commonly caused by high fat content, being sedentary, or both (2). Other contributing factors include genetic factors (metabolism and hormone regulation) (3), cultural cuisine, environmental factors (physical activity in temperate, safe areas has been replaced by sedentary behaviors like television viewing, which has been cited as a cause of obesity) (4) and social determinants (financial and time-related barriers to healthy behavior modeling) (5). Unfortunately, overweight children are not likely to return to normal weight later in life (6). Childhood overweight is an associated risk factor for severe obesity over the life course into adulthood (7). This has serious health implications for our youth. Overweight and obese adults are at increased risk of many diseases and chronic conditions, including osteoarthritis, coronary heart disease, type 2 diabetes and certain cancers (8). Although these conditions become a more realistic risk later on in life, overweight in childhood and adolescence paves the way for overweight in adulthood when the risk for developing these diseases is more imminent.
School-based health programs are becoming increasingly popular as educators, healthcare providers, parents and public health professionals seek effective methods to prevent childhood obesity. This population-based approach is broad enough to reach many students. Many programs focus on dietary education and increasing physical activity. For example, school-based dietary education classes focus on reducing students’ consumption of sugary drinks and increasing fruit and vegetable consumption. Physical activity programs, like SPARK (Sports, Play and Active Recreation for Kids) often provide three 30-minute sessions of rigorous physical activity per week (9). Although popular school-based approaches that target major root causes of adolescent obesity are integral in reversing its growing trend and the increasing onset of obesity-related disease, these interventions fall short by focusing on students’ isolated behaviors, like unhealthy eating habits and lack of physical activities, without addressing external factors linked to student behavior. This shortsighted approach may not be enough to make lasting changes. Until school-based interventions consider external factors such as modeling, group dynamics and environmental barriers that weigh heavily on adolescents’ choices, these programs will continue to fall short of their potential to reach students.
Current Interventions to Treat Obesity Neglect the Power of Modeling
Schools that implement physical activity programs geared towards lowering students’ BMI focus solely on one individual behavior and fail to address external influencing factors, such as behaviors exhibited by others surrounding them, positive or negative reinforcements given as responses to their behaviors and their perceptions about their situation (10). Likewise, dietary education programs that teach students to reduce sugar consumption often fail to extend their curriculum to students’ parents. According to Social Learning Theory, consideration of external factors is just as important as addressing individual factors. It is the interactions of these multi-level influences that result in behaviors.
Parents play an important role in their children’s lives, especially as they develop through their childhoods (11). By the time they have reached adolescence, youth have internalized certain habits that they have seen around them, including dietary and exercise habits, resulting in vicarious learning (10). Gastroenterologists have conducted studies on behavior therapy regarding weight loss on the basis of social learning theory—behaviors that contribute to obesity (such as overeating and participating in sedentary activities) are learned. Conversely, behaviors that promote health could be learned as well (12). Failing to inform parents of program objectives can work against progress made in school because students will not have positive models once they leave their school setting. No matter how effective a physical activity program is in temporarily reducing BMI levels, gained health benefits are not sustainable unless students are observing healthy dietary and exercise habits in other compartments of their lives, exemplified by their parents, families, and other adults that they look up to.
Current Interventions Neglect Adolescents’ Group Dynamics in Social Networks
By strictly addressing individual behaviors, physical activity and dietary education school-based programs are not able to take into account the complex effect of students’ social networks. Students’ social networks include friends, acquaintances, family members, teachers, peers and teammates. Social Network Theory highlights the importance of relationships between individuals rather than their specific individual behaviors. The impact that relationships have over someone’s personal decisions are determined by the nature of the relationships—for example, frequency and complexity of interactions, social or academic settings, reciprocity of the relationship, among other factors (10).
Studies have shown that individuals’ chances of becoming obese are greater if they are surrounded by others who are obese, suggesting that weight gain develops in clusters through social ties. This finding is consistent with the Group Dynamics line of thought, which posits that one’s behavior can best explained by his or her group associations, not by individual factors. A study that was part of the Framingham Heart Study showed that being friends with an obese person increased someone’s risk of becoming obese by 57% (13). Similarly, having a sibling who becomes obese increased someone’s risk of becoming obese by 40%.
Obesity in friends may change an individual’s perception of the acceptability of being overweight, a mechanism commonly called anchoring (14). Considering that adolescents are going through a complex combination of biological, cognitive and psychological changes simultaneously, they are particularly impressionable during their school-aged years. Having obese friends may normalize obesity and therefore have negative effects on student behaviors. The Framingham Heart Study also showed that weight gain by same sex friends and siblings had a larger impact on the risk of becoming obese him- or herself—providing another supportive argument for the social influence of weight gain. Adolescents are more influenced by those that have resemblance to themselves (13).
Current Interventions Fail to Address Ways to Overcome Socioeconomic and Cultural Barriers
School-based interventions that are focused on students’ eating and exercising habits offer no practical solutions to overcome barriers to access healthy foods and safe environments for exercise. When socioeconomic factors create financial and physical barriers to healthy behaviors, well-reasoned health beliefs may not be enough (15). For example, if the only options available to students in school are sugary drinks and snacks dispensed from a vending machine, any adolescent’s good intention to eat well can amount to very little progress. In the same vein, some schools and neighborhoods may not have well-stocked grocery stores with fresh produce in accessible locations, making it difficult for locals to even obtain healthy foods. The repercussions of these barriers are reflected in the prevalence of obesity in the United States—obesity was reported to be highest among those with low education attainment (less than a high school degree) and among the Black population (16)—factors that are risk markers for low socioeconomic status. These findings indicate that socioeconomic status is a key factor in obesity outcomes and must be integrated into school-based health programs to be appropriately tailored for the student body.
In conjunction with socioeconomic status barriers, cultural barriers also play a role in students’ choices. In many schools, students find their social niches through social hangouts. Fast food stores represent not only an outlet for tasty menu items, but also a place to belong to. Especially in areas of lower socioeconomic status, the thorough infiltration of the fast food industry can become a cultural barrier to healthy choices and can severely undermine school-based approaches. In addition to the strong presence of fast food and unavailability of healthy food stores, students living in dangerous neighborhoods do not have the freedom to be active outdoors, decreasing their physical activity opportunities. To address these cultural barriers, one strategy might be to provide community centers and other safe hangout areas for adolescents where healthy food options are more readily available. This approach is supported by the Social Cognitive Theory, which says that in order for students to change behaviors, they must be shown that they have actually can make those choices and believe in their ability to act on their good intentions.
Childhood and adolescent obesity has been emerging for over three decades and is no longer an issue that can be ignored. Many communities have taken action by implementing school-based programs to reach young people. Now that preventing and treating obesity has successfully reached the national health agenda, it is time to start maximizing the efficiency of school-based programs by thoughtfully considering social and environmental factors that will play a role in the students’ learning and decision-making process. Dietary education and physical activity are two basic components of combating obesity. Efforts to include parents in the health curriculum would increase chances of healthy behavior modeling. Integrating the power of social networks into the structure of a health program would deliver the message more efficiently to students. Finally, addressing cultural and financial barriers within the curriculum would provide students and their families with practical ways to improve their behaviors by reinforcing self-efficacy. Integrating behavior theories into interventions will increase not only their immediate success but also increase sustainability of students’ behaviors throughout their lifetimes.
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  • At April 25, 2008 at 3:07 PM , Blogger Elizabeth Victoria said...

    Great arguments, and clever title! I think that the idea of avoiding obesity as a horrible monster of doom is less effective than working from a more positive perspective. For instance, instead of pouring money into finding out how many and what type of children are obese, we might be better served as a culture by spending it on parks and places where kids can go play freely. Not only is this less frightening, it's preventative, which makes more viable economically.


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