OBJECTIVE: Stressors, such as adverse life events, can cause weight changes through behavioral and biological mechanisms. Whether the accumulation of adverse life events is related to body mass index (BMI) across multiple time points from early adolescence to young adulthood has not been investigated to date.

METHODS: Data are from 2188 children participating at T1 (10-12 years), T3 (14-18 years), and/or T5 (21-23 years) of the prospective Tracking Adolescents' Individual Lives Survey cohort study. Adverse events before T1 and between T1, T3, and T5 were measured with a parent interview at T1 and a semistructured interview (Event History Calendar) with the adolescent at T3 and T5. An adverse events score was calculated per wave. Body mass index z-scores were determined from objectively measured height and weight using the LMS (skewness, median, and coefficient of variation) reference curves of the International Obesity Task Force for children 18 years or younger. Data were analyzed using a modified bivariate autoregressive cross-lagged structural equation model.

RESULTS: Adverse events before T1 and between T3 and T5 were related to BMI at T5 (β = 0.06, p = .001 and β = -0.04, p = .04, respectively). Specifically, health events before T1 were associated with a higher BMI at T5, and events related to relationships and victimhood events between T3 and T5 were associated with a lower BMI at T5.

CONCLUSIONS: Adverse relationship and victimhood events in their recent past were related to a lower BMI in young adults, whereas adverse health events during childhood were related to a higher BMI in young adults. No relationships were found between adverse life events with BMI in children and adolescents.