(PS5-77) Toward a biopsychosocial theory of food insecurity and eating disorder psychopathology: Exploring the roles of circadian-disrupted eating and shame

Despite the stereotype that eating disorders (EDs) occur primarily in affluent communities, ED psychopathology is associated with food insecurity (FI; Hazzard et al., 2020). The relation between ED psychopathology and FI may be explained by shame secondary to internalized stigma (Becker et al., 2021). However, ED psychopathology is also associated with irregular eating patterns (e.g., meal omission, evening-shifted eating; Bottera & De Young, 2022). Because eating is a potent zeitgeber for entraining circadian rhythm, and FI is a context ripe for circadian disruption, irregular eating might also explain the association between FI and ED psychopathology. Together, accounting for the potential roles of both shame and eating regularity will refine a novel biopsychosocial theory of FI and ED psychopathology. Undergraduates (N = 255) ages 18-50 years old (M = 19.85; SD = 3.59; 70.2% assigned female sex at birth; 92.6% cisgender; 83.5% White) completed an online survey. Most participants were highly (n = 108, 42.4%) or marginally (n = 75, 29.4%) food secure. Two cross-sectional multiple mediator models were conducted using SPSS PROCESS Model 4 (Hayes, 2018), with two indirect paths from USDA FI scores to ED psychopathology (i.e., EPSI binge eating and purging scores, respectively). Mediators included shame proneness and three circadian facets of eating regularity: circadian omission (i.e., the regularity at which eating events occurred across days), circadian timing (i.e., the regularity at which eating events occurred at the same times across days), and homeostatic spacing (i.e., the spacing between eating events within days). Shame was directly associated with binge eating (std. B = .158, p = .020) and purging (std. B = .159, p = .021) scores, but not with FI. There was an indirect effect of FI on binge eating scores through between-day variability in eating pattern (i.e., skipping; std. B = .025) and a direct effect of variable within-day spacing between eating events on purging scores (std. B = .147, p = .033). There were no indirect effects of FI on purging psychopathology through hypothesized biopsychosocial mediators. The relation between FI and binge eating may be partially explained by irregular eating patterns consistent with suboptimal circadian regulation of feeding. Future research should use longitudinal methods to establish temporal precedence and ordering necessary to infer causality and evaluate potential protective factors that could mitigate the effect of FI on binge eating through irregular eating.