Shifting the Scale: A Cognitive Dissonance Approach to Reducing Explicit and Implicit Anti-Fat Bias in Premedical Students

Over the past two decades, weight stigma has remained a pervasive form of bias. Healthcare providers are among the most frequent sources of weight-based discrimination, with significant consequences for patient trust, healthcare utilization, and outcomes. To address these biases early in professional development, the present study tested a brief, theory-driven intervention targeting both implicit and explicit anti-fat attitudes in premedical undergraduates. Grounded in cognitive dissonance theory and integrating principles from attribution theory, social identity theory, and sociocultural theory, components of the intervention included educational materials, a counterattitudinal essay, and a public pledge. Participants (N = 51) were randomly assigned to an intervention or control condition and completed pre- and posttest measures of implicit and explicit bias via an implicit association test (IAT) and surveys. Results indicated significant reductions in both implicit and explicit anti-fat bias among participants in the intervention condition, with medium–large effect sizes. Moderation analyses showed that intervention effects on implicit attitudes were strongest among individuals low in weight bias internalization. These findings suggest that dissonance-based interventions, particularly when supplemented with bias-relevant content, can reduce weight stigma at both explicit and automatic levels. The present study demonstrates a single-session strategy capable of reducing bias in pre-health populations, with implications for early intervention in healthcare training.