Objective: To synthesize what is known about how celebrities influence people’s decisions on health.
Design: Meta-narrative analysis of economics, marketing, psychology, and sociology literatures.
Data Sources: Systematic searches of electronic databases: BusinessSource Complete (1886-), Communication & Mass Media Complete (1915-), Humanities Abstracts (1984-), ProQuest Political Science (1985-), PsycINFO (1806-), PubMed (1966-), and Sociology Abstracts (1952-).
Inclusion Criteria: Studies discussing mechanisms of celebrities’ influence on people in any context.
Results: Economics literature shows that celebrity endorsements act as signals of credibility that differentiate products or ideas from competitors and can catalyze herd behaviour. Marketing studies show that celebrities transfer their desirable attributes to products and use their success to boost their perceived credibility. Psychology shows that people are classically conditioned to react positively to the advice of celebrities, experience cognitive dissonance if they do not, and are influenced by congruencies with their self conceptions. Sociology helps explain the spread of celebrity medical advice as a contagion that diffuses through social networks and people’s desire to acquire celebrities’ social capital.
Conclusion: The influence of celebrity status is a deeply rooted process that can be harnessed for good or abused for harm. A better understanding of celebrity can empower health professionals to take this phenomenon seriously and use patient encounters to educate the public about sources of health information and their trustworthiness. Public health authorities can use these insights to implement regulations and restrictions on celebrity endorsements and design counter marketing initiatives—perhaps even partnering with celebrities—to discredit bogus medical advice while promoting evidence based practices.