Performing emotional labor impairs mood as well as regulatory control of employees, and we compare these mechanisms to explain critical health-related behaviors: eating and exercise. Two studies examine the relationship of surface acting at work with unhealthy eating and physical activity at home as mediated by negative and positive affect. Emotion regulation (ER) self-efficacy is tested as a moderator of the indirect relationships. Also, the relative strength of the affect mechanisms and a depletion mechanism are explored. Study 1 utilized a time-lagged between-person design to explore these relationships among 287 customer service workers. Results show that surface acting has an indirect link with unhealthy eating via negative affect and an indirect link with physical activity via positive affect. ER self-efficacy moderates the path from negative affect to unhealthy eating, thereby weakening the indirect effect of surface acting on unhealthy eating via negative affect. Study 2 utilized a 5-week diary study of 469 teachers to replicate Study 1 at the within-person level. Results show that surface acting has indirect effects on unhealthy eating and physical activity via negative affect at the week level. Also, surface acting has an indirect effect on physical activity via positive affect at the week level. Again, ER self-efficacy cross-moderates (weakens) the indirect link between surface acting and unhealthy eating via negative affect. The pairwise comparisons of the indirect effects reveal no differences among the affect mediators (Studies 1 and 2); however, positive affect may account for more of the effect of surface acting on physical activity than depletion (Study 2). (PsycInfo Database Record (c) 2022 APA, all rights reserved).