Fitmom: an experimental investigation of the effect of social media on body dissatisfaction and eating and physical activity intentions, attitudes, and behaviours among postpartum mothers

Research has shown that body dissatisfaction is higher during the postpartum period compared to other periods of life, and strongly associated with disordered eating behaviours, which can lead to adverse health outcomes. While results from cross-sectional studies suggest that social media may play an important role in body dissatisfaction among postpartum mothers, causal inference is limited due to the observational nature of the existing research. The objective of this study is to experimentally test the effect of body-focused social media on the body dissatisfaction and eating and physical activity intentions, attitudes, and behaviours of postpartum mothers. Postpartum mothers of infants 0-6 months (n = 132) were randomly assigned to view either body-focused social media posts (n = 65), or a control set of infant feeding tips (n = 67). ANCOVA was used to examine differences between the intervention and control group on levels of body dissatisfaction, eating and physical activity intentions, attitudes, and behaviours. There were two follow-up time points, immediately post intervention and 1-month post intervention to measure potential sustained effects of intervention. Exposure to body-focused social media posts resulted in higher levels of body dissatisfaction, mean difference 1.54 (p = 0.002); poorer body image, mean difference 0.41 (p = 0.007); eating attitudes, mean difference 2.26 (p = 0.025); and higher levels of restrained eating behaviours, mean difference 0.39 (p