Fat Talk Free Week (FTFW), a social marketing campaign designed to decrease self-disparaging talk about body and weight, has not yet been evaluated. We conducted a theory-informed pilot evaluation of FTFW with two college samples using a pre- and posttest design. Aligned with the central tenets of the Elaboration Likelihood Model (ELM), we investigated the importance of FTFW saliency as a predictor of fat talk behavior change. Our analytic sample consisted of 118 female participants (83% of original sample). Approximately 76% of the sample was non-Hispanic White, 14% Asian, and 8% Hispanic. At baseline, more than 50% of respondents reported engaging in frequent self fat talk; at posttest, this number dropped to 34% of respondents. Multivariable regression models supported campaign saliency as the single strongest predictor of a decrease in self fat talk. Our results support the social diffusion of campaign messages among shared communities, as we found significant decreases in fat talk among campaign attenders and nonattenders. FTFW may be a promising short-term health communication campaign to reduce fat talk, as campaign messages are salient among university women and may encourage interpersonal communication.