Shifting peer norms, shifting behavior? Optimizing educational interventions to promote adolescents’ sustainable dietary choices

Two preregistered randomized experiments (Study 1: N = 381, age 12–17, 47.5 % girls, 90 % Dutch; Study 2: N = 468, age 12–19, 52.8 % girls, 79.7 % Dutch) tested whether educational interventions to promote adolescents' sustainable behavior can be optimized by harnessing their peer status motive. Across studies, Bayesian informative hypothesis testing indicated strong support (PMPs 0.896 to 0.981, BFs 10.02 to 58.03) for the hypothesis that educational messaging promoted adolescents' sustainable dietary behavior and behavior intentions compared to unrelated messaging; that peer norm messaging amplified the motivational effect of education; and that dynamic (“more and more youth choose to eat less meat”) and static (“some youth choose to eat less meat”) norm messaging was equally effective. Effect sizes were small to medium. These findings suggest that educational interventions more effectively promote adolescents’ sustainable behavior when tailored to their developmentally salient peer status motive. • In two experiments, we tested ways to promote adolescents' sustainable behavior. • Educational messaging promoted adolescents' sustainable dietary behavior. • Peer norm messaging amplified the motivational effect of educational messaging. • Dynamic and static peer norm messaging was equally effective.