Forget sneaking out and partying. Rebellious teens can fight the system by cutting out processed foods and eating more fruits and vegetables.

A team of psychologists found that teenagers’ desires to gain respect and be activists can be manipulated to develop healthy eating habits. By portraying the food industry as exploitative and unfair, middle school students were more likely to pick healthier snacks. The study was published Sept. 12 in Proceedings of the National Academy of Sciences in the United States of America.

Students were separated into two groups. The control group read health textbooks describing the food pyramid and how to read nutrition labels and were asked to write an essay on the importance of healthy eating. The other group read journalistic pieces about the food industry’s harmful marketing practices, deceptive labeling and targeting of children and low-income groups. Researchers showed them quotes from older classmates describing their outrage and plans to eat healthily.

A few months later, the students were offered snack options at school. Researchers found that students from the second group were more likely to pick healthy foods, such as fruit or nuts, over snacks like cookies or soda. 

Researchers found that this approach — casting healthy eating as activism — was more effective than traditional health education in the study, said Cintia Hinojosa, UT psychology alumna, lab manager at the University of Chicago and co-author of the study.

“Teen brains are more motivated by autonomy and having a purpose greater than themselves,” Hinojosa said. “Adults are more motivated by self-interest — we’re better able to focus on future goals.”

The researchers were inspired to design the study by the anti-smoking Truth campaign, which teaches teens about manipulative tactics in the tobacco industry, according to Hinojosa. The Truth campaign is social justice-oriented and focuses on a greater movement, rather than just individual health.

Current anti-obesity initiatives are flawed in that they are not designed with teenage mindsets in consideration, Hinojosa said.

“Adolescents normally view healthy eating as not that cool and something your parents tell you to do,” said David Yeager, assistant psychology professor at UT and co-author of the study. “Health class messages that make the teen choose between status and eating healthy are going to lose.”

Teenagers tend to have more free time and spending money than children, which allows them to buy unhealthy food and can contribute to obesity. In-school initiatives that leave deep impressions on students can lead to them making healthy choices in school and beyond, Yeager said.

The researchers’ next step is to see if teens retain these healthy behaviors by tracking their cafeteria purchases over time. They also would like to track students’ cortisone levels through saliva samples, in order to see if stressed reactions to information on unfair practices are correlated with altered behavior.

In the future, Hinojosa said teachers and psychologists may apply these results to intervention programs for adolescent behavior. According to Hinojosa, an understanding of teenage psychology can help parents and educators work with their teens.

“Having them incorporate healthy eating as part of their identity will hopefully hold as they become adults,” Hinojosa said. “It’s easier for teens to do now that the internet is a huge source of information, so they’re able to stay socially conscious and make decisions that align with a positive movement.”