Abstract
Adolescents often engage in behaviors posing significant risks to their health (e.g., substance abuse, sexual promiscuity). One explanation is that adolescence is a developmental phase characterized by impulsiveness and poor judgment of contingencies and risk. We present an alternative uncertainty-identity theory analysis that focuses on adolescence as a period of identity transition. Adolescents are confronted by significant uncertainty about who they are and how they should behave, and they largely turn to their peers to ground their sense of self. They engage in risky health practices because these behaviors define adolescent groups that provide a highly distinctive sense of self and identity that is validated and imbued with prestige by their peers. We asses empirical support for this analysis, and suggest factors that may protect adolescents from uncertainty-motivated identification with unhealthy groups.