Influence of Childhood and Adolescent Fat Development on Fat Mass Accrual During Emerging Adulthood: A 20-Year Longitudinal Study

Abstract

Objective: Fat mass and the prevalence of overweight/obesity (OWO) increase during emerging adulthood (EA; 18-25 years). The factors that contribute to the transition from having healthy weight to having OWO during EA are understudied. This study aimed to identify the independent effect of concurrent physical activity (PA) and energy intake (EI) and childhood/adolescent fat accrual, PA, and EI on EA fat accrual. Methods: One hundred twenty-six participants (59 male) were measured serially between 1991 and 2011. Measures included age, height, weight, total body and trunk fat mass (TBF and TrF, in grams) derived from dual-energy x-ray absorptiometry, and PA and EI. Composite childhood/adolescent z scores were calculated for each participant (average mean z score) for TBF, TrF, PA, and EI. Multilevel random-effects models were developed. Results: EA fat accrual was predicted by childhood and adolescent TBF and TrF z score (0.30 ± 0.05, P < 0.05), respectively, in both sexes. Concurrent PA (−0.06 ± 0.02, P < 0.05) was significant in males only. Conclusions: These results underscore the importance of maintaining a lower TBF and TrF during childhood and adolescence, and a higher level of PA in order to mitigate TBF and TrF accrual and prevent the transition from having healthy weight to having OWO during EA.