In the previous Project Health trial, the investigators found Project Health is most effective when implemented in single sex groups paired with food specific response and attention training. This project will evaluate the effectiveness of this version of the Project Health intervention compared to a video control condition and is an important step toward dissemination. A brief effective obesity prevention program that can be easily, inexpensively, and broadly implemented to late adolescents at risk for excess weight gain, as has been the case with another dissonance-based prevention program, could markedly reduce the prevalence of obesity and associated morbidity and mortality. The program may also have an important secondary benefit of preventing the onset of future eating symptoms and disorders. The study has 2 aims: (1) Test the hypothesis that Project Health implemented in single-sex groups and paired with food response inhibition and attention training produces significantly larger weight gain and overweight/obesity onset prevention effects than an educational video control condition (primary outcome). (2) Test the hypothesis that Project Health implemented in single-sex groups and paired with food response inhibition and attention training produces significantly larger eating disorder symptom prevention effects than an educational video control condition (secondary outcome).
