Relationships Between Meaning in Life, Positive and Negative Affect, and Eating Behaviors: A Daily Diary Study

Meaning in life (MIL) is crucial in promoting health behaviors; nevertheless, the mechanism underlying the relationship between MIL and health behaviors remains unclear. This study aimed to investigate the relationships between MIL and eating behaviors (i.e., healthy and emotional eating), and the mediating roles of positive and negative affect. A total of 113 Chinese undergraduate students (83.2% women; mean age = 19.84 years) were recruited to complete 14 consecutive days of assessments on MIL, positive and negative affect, healthy eating, and emotional eating. The proposed multilevel structural equation model showed that the within-person indirect effects of “MIL → positive affect → healthy eating” and “MIL → negative affect → emotional eating” were significant. These findings suggested that on within-person levels, daily MIL is positively associated with same-day healthy eating directly or indirectly via positive affect; daily MIL is negatively associated with same-day emotional eating via negative affect. Therefore, more attention should be paid to increasing daily MIL when designing interventions for health behaviors.