Examining the impact of pharmacist professionalism and celebrity endorsers on dietary supplement purchase intention: the moderating role of product knowledge

Purpose: This study aims to explore how consumers’ purchase intentions concerning dietary supplements are affected by two pivotal factors: pharmacist professionalism and celebrity endorser attractiveness. In addition, this study investigates the moderating role of consumers’ awareness of product knowledge about dietary supplements in the relationship between brand trust and purchase intention. Design/methodology/approach: The research data was collected through online questionnaires from a convenience sample of 340 individuals residing in Taiwan. The research model, consisting of four hypotheses, was formulated based on a literature review. The partial least squares structural equation modeling technique was used for data analysis. Findings: The findings indicate positive effects of both pharmacist professionalism and celebrity endorser attractiveness on dietary supplement brand trust. The results also suggest a significant impact of brand trust on purchase intention. Finally, product knowledge significantly moderates the relationship between brand trust and purchase intention. Practical implications: The findings from this study provide valuable insights for marketers, pharmacists and practitioners about the drivers of consumers’ dietary supplement purchase behavior. It will enable marketers to develop better strategies for the dietary supplement market segment. Originality/value: This paper has made a significant contribution to the understanding of consumer buying intentions toward dietary supplements, addressing a gap in the literature. First, unlike previous research, this study considers both pharmacist professionalism and celebrity endorser attractiveness in the research model, effectively bridging this gap. Furthermore, this study identifies the pivotal role of brand trust as a critical factor in enhancing consumers’ purchase intentions toward dietary supplements, offering valuable insights for dietary supplement companies regarding consumer purchase decision-making.