Beyond youth: The optimal age for influencer credibility and marketing success
研究发现影响者的外表年龄与营销效果呈倒U型关系，中等年龄表现最佳，挑战了“年轻即好”的传统观念，为品牌和创作者提供了年龄策略参考。
Abstract Influencer marketing has traditionally celebrated youth as the key to engagement. However, with the rise of AI-powered appearance manipulation, influencers can strategically curate their age. This study explores how apparent age shapes marketing outcomes, challenging the conventional wisdom that youth always sells. Drawing on Source Credibility Theory, we examine how age influences credibility (the compound of expertise/trustworthiness) and attractiveness, hypothesising a Goldilocks effect where moderate ages yield optimal results. Across four pre-registered studies using experimental, field-experimental and observational designs, we reveal an inverted U-shaped pattern: extremely young or old appearances underperform, while moderate age leads to peak engagement. Independent manipulations confirm that age raises credibility, lowers attractiveness, and that these dimensions interact to shape outcomes; moderators (AI disclosure, gender, audience age, or homophily) shift or bend the curve as predicted. We introduce age appearance as a strategic lever for brands, creators, and platforms in the era of digital identity manipulation.