RÉSUMÉ
OBJECTIVE: Loss-of-control and overeating are common in adolescents with high body mass index (BMI). Mindfulness may affect negative affect, and both may relate to loss-of-control and overeating. Yet, there is limited understanding of these associations in adolescents' daily lives. METHODS: Forty-five adolescents (77% female; Mage = 14.4 years, SDage = 1.7 years) with high weight (92% with BMI [kg/m2 ] ≥85th percentile for age/sex) provided daily, repeated measurements of mindfulness, negative affect, loss-of-control, and overeating for ~7 days (M = 5.6 days; range = 1-13). Multilevel mixed modeling was conducted to test within-person (intraindividual) and between-person (interindividual) associations for the same-day (concurrent) and next-day (time-ordered/prospective). RESULTS: There were within-person and between-person associations of higher mindfulness with lower negative affect on the same-day and next-day. Greater between-person mindfulness related to lower odds of adolescents' loss-of-control occurrence (same-day) and conversely, more perceived control over eating (same-day and next-day). Greater within-person mindfulness related to less odds of next-day overeating. DISCUSSION: Dynamic relations exist among mindfulness, negative affect, and eating in adolescents at-risk for excess weight gain. Mindfulness may be an important element to consider in loss-of-control and overeating. Future work using momentary-data within an experimental design would help disentangle the intraindividual effects of increasing mindfulness/decreasing negative affect on disordered eating. PUBLIC SIGNIFICANCE: Loss-of-control and overeating are common in teenagers with high weight. Greater mindfulness-present-moment, non-judgmental attention-and less negative emotions may relate to healthier eating, but we do not know how these processes play out in teenagers' daily lives. Addressing this knowledge gap, the current findings showed that greater daily mindfulness, but not negative affect, related to less loss-of-control/overeating, suggesting the importance of mindfulness for eating patterns in teenagers' daily lives.