Abstract
BACKGROUND: Adverse childhood experiences (ACEs) are a risk factor for obesity; however, the causal mechanisms are not well understood. Objectives were to measure the impact of ACEs on adulthood obesity and to investigate whether the association was mediated by nutrition and stress. METHODS: A longitudinal study was conducted using adults aged 46-90 years (n = 26 615) from the Canadian Longitudinal Study on Aging. Participants were asked to recall ACEs from <18 years of age. Body mass index (BMI), waist circumference and per cent body fat were measured (2015-18) and obesity was defined using standard cut points. Nutrition was measured using data from the Short Diet Questionnaire and stress was measured using allostatic load. Multinomial logistic regression was used to estimate odds ratios (ORs) and 95% CIs for each obesity measure. Causal mediation methods were used to determine whether nutrition and stress were mediators. RESULTS: There were 66% of adults who had experienced one or more ACE. The odds of obesity defined by BMI and waist circumference increased in a dose-response manner with increasing number of ACEs (P trend <0.001). For instance, adults with four to eight ACEs, compared with none, had greater odds of obesity, defined by BMI (adjusted OR: 1.54; 95% CI: 1.28-1.75) and waist circumference (adjusted OR: 1.30; 95% CI: 1.15-1.47). There was no evidence of mediation by stress or nutrition. CONCLUSIONS: Adversity experienced in early life is strongly associated with obesity among Canadian adults. Further research is needed to identify other mechanisms for this association to inform obesity prevention strategies.