Inoculating teens against junk food marketing possible, study finds

A new study from the University of Chicago Booth School of Business finds that a simple and brief intervention can reframe how students view food-marketing campaigns, which can spur adolescents, particularly boys, to make healthier daily dietary choices for an extended period of time. The method works in part by tapping into teens’ natural desire to rebel against authority. The latest study “A Values-Alignment Intervention Protects Adolescents from the Effects of Food Marketing” by Chicago Booth’s Christopher Bryan, University of Texas at Austin’s David Yeager, and Booth PhD candidate Cintia Hinojosa, has been published recently in Nature Human Behaviour. A preliminary study took place among eighth graders at a Texas middle school in 2016. The researchers went into classrooms and had one group of students read a fact-based, exposé-style article on big food companies. The article framed the corporations as manipulative marketers trying to hook consumers on addictive junk food for financial gain. The stories also described deceptive product labels and advertising practices that target vulnerable populations, including very young children and the poor. A separate, control group of students received traditional material from existing health education programs about the benefits of healthy eating. The researchers found the group that read the exposés chose fewer junk food snacks and selected water over sugary sodas the next day. In the latest round of research, teens first read the marketing exposé material and then did an activity called “Make It True,” meant to reinforce the negative portrayal of food marketing. The students received images of food advertisements on iPads with instructions to write or draw on the ads—graffiti style—to transform the ads from false to true. The latest study, which used a new sample of eighth graders, found that the effects of the marketing exposé intervention endured for the remainder of the school year—a full three months. The effects were particularly impressive among boys, who reduced their daily purchases of unhealthy drinks and snacks in the school cafeteria by 31% in that time period, compared with the control group. Among the two biggest findings in the experiment: the intervention produced an enduring change in both boys’ and girls’ immediate, gut-level, emotional reactions to junk food marketing messages. And teenage boys, a notoriously difficult group to convince when it comes to giving up junk food, started making healthier food and drink choices in their school cafeteria. Bryan said that food marketing is deliberately designed to create positive emotional associations with junk food, to connect it with feelings of happiness and fun. “What we’ve done is turn that around on the food marketers by exposing this manipulation to teenagers, triggering their natural strong aversion to being controlled by adults. If we could make more kids aware of that, it might make a real difference.” This study shows it's possible to change behaviour during adolescence using a light-touch intervention by appealing to teenagers’ natural impulse to “stick it to the man” and their developmentally heightened sense of fairness. It may provide a way for the public-health community to compete against junk food marketers. “One of the most exciting things is that we got kids to have a more negative immediate gut reaction to junk food and junk food marketing, and a more positive immediate gut reaction to healthy foods,” Bryan added. In a bid to fight obesity, public-health researchers have been trying for decades to find a way to convince teenagers to skip junk food and eat healthily, to little avail. One of the biggest obstacles is the enormous volume of food marketing kids are exposed to every day. That marketing is designed to foster strong positive associations with junk food in kids’ minds and to drive overeating—and research has shown that it works. “Most past interventions seemed to assume that alerting teenagers to the negative long-term health consequences of bad diets would be an effective way to motivate them to change their behaviour,” said Bryan. “That’s clearly a problematic assumption. We thought it could be the main reason why no one has been able to get teenagers to change their eating habits in a lasting way.”