Testing "Feeling Fat" as a Mediator of the Longitudinal Relationship Between Negative Emotions and Eating Disorder...

Negative affect is central to eating disorder maintenance models; identifying mechanisms underlying this link may inform specific treatment targets. The current study evaluated which emotions (i.e., distress, fear, and moral emotions) were most strongly linked to feeling fat and tested feeling fat as a longitudinal mediator of the relationship between these emotions and restricting or binge eating (https://osf.io/3d5cq/).

Community adults (N = 714, M[SD] age = 41.5[13.7], 84.6% female, 85.9% white) provided data at baseline, 3-month, and 6-month follow-up. Relative weights analysis examined which emotion categories exhibited the strongest longitudinal relationships with feeling fat. Cross-lagged panel models tested feeling fat as a mediator of the relationship between emotions and eating disorder behaviors.

Distress and moral emotions were the strongest emotional predictors of feeling fat. Feeling fat predicted binge eating (p's < 0.001), but not restricting (p's ≥ 0.832), in random effects cross-lagged panel models. Feeling fat partially mediated the longitudinal relationship between distress and binge eating (p = 0.044); however, this effect became nonsignificant after adjusting for BMI (p = 0.354). Feeling fat did not mediate relationships between moral emotions and binge eating or between either distress or moral emotions and restricting (p's ≥ 0.638).

Feeling fat was associated with binge eating, not restricting, highlighting the importance of specificity in maintenance models. Because the mediating effect of feeling fat was accounted for by body size, factors associated with body size, such as internalized weight stigma, may be more relevant mediators of the relationship between negative emotions and eating disorder behaviors. Future research on feeling fat should adjust for body size.