Athanasios Poulis, Prokopis K. Theodoridis, Theofanis Zacharatos
This study examines digital sustainability signals and the psychological mechanisms (authenticity and trust) that relate to consumers’ sustainable food purchase intentions. While the attitude–behavior gap remains a persistent challenge in sustainability research, our study focuses on upstream factors that may help explain why intentions vary in strength. Drawing on signaling theory, this research develops and tests a framework that combines positive signals (e.g., influencer credibility) and negative signals (e.g., perceived greenwashing) to investigate the impact on green brand authenticity, brand trust, and purchase intention. Data were gathered from a survey of 324 adult social media users who follow influencers with a focus on sustainability and have recent experience buying eco-labeled food products. Using PLS-SEM, results indicate that influencer credibility has a significant and positive effect on perceptions of green brand authenticity, whereas the influence of greenwashing has a significant and negative effect. Authenticity shows a strong prediction of brand trust, and this in turn predicts green purchase intentions with trust mediating the authenticity–intention relationship to some degree. The results indicate authenticity as a key mechanism by which digital signals affect sustainable consumption. The research provides practical insights for food brands seeking to strengthen the psychological conditions that support sustainable consumption intentions.