Daily Bi-directional effects of women's social media-based appearance comparisons, body satisfaction, and disordered eating urges.

We assessed the bi-directional relationships between upward appearance comparisons on social media with body dissatisfaction (BD) and disordered eating (DE) in women's daily lives and the potential moderating effect of trait self-objectification on these relationships. Women (N = 315) completed a baseline measure of trait self-objectification, then reported momentary experiences of social media-based appearance comparisons (upward, lateral, downward), body satisfaction, and DE urges (restrict food intake, exercise, overeat) for seven days. We hypothesized that upward (relative to no) comparisons would predict lower body satisfaction and higher DE urges, while lateral and downward (relative to no) comparisons would predict higher body satisfaction and lower DE urges. We expected these relationships to be bi-directional and moderated by trait self-objectification. Multilevel modelling results revealed complex bi-directional relationships. Upward comparisons predicted lower body satisfaction and increased urges to restrict food intake, which in turn predicted increased upward comparisons. Unexpectedly, urges to restrict food intake predicted all comparison types. We observed somewhat unanticipated bi-directional relationships between lateral comparisons and exercise urges, and between downward comparisons and body satisfaction. Uni-directional relationships emerged between upward comparisons and the urge to overeat. Trait self-objectification moderated very few of these relationships. These findings support the non-uniform impact of appearance comparisons on body image and eating concerns and highlight the complexity of daily social media-body image dynamics. Future research using refined measures over extended periods is needed to elucidate these relationships further and inform targeted interventions.