Beliefs in mind-body dualism--that is, perceiving one's mind and body as two distinct entities--are evident in virtually all human cultures. Despite their prevalence, surprisingly little is known about the psychological implications of holding such beliefs. In the research reported here, we investigated the relationship between dualistic beliefs and health behaviors. We theorized that holding dualistic beliefs leads people to perceive their body as a mere "shell" and, thus, to neglect it. Supporting this hypothesis, our results showed that participants who were primed with dualism reported less engagement in healthy behaviors and less positive attitudes toward such behaviors than did participants primed with physicalism. Additionally, we investigated the bidirectionality of this link. Activating health-related concepts affected participants' subsequently reported metaphysical beliefs in mind-body dualism. A final set of studies demonstrated that participants primed with dualism make real-life decisions that may ultimately compromise their physical health (e.g., consuming unhealthy food). These findings have potential implications for health interventions.