Undergraduate women who join a sorority are more likely to judge their own bodies from an outsider's perspective (known as self-objectification) and display higher levels of bulimic attitudes and behaviors than those who do not take part in the sorority's recruitment process. Over time, those women who join the group also show higher levels of body shame.

These findings, part of Ashley Marie Rolnik's senior honors thesis at Northwestern University in the US, are published online in Springer's journal Sex Roles.

On college campuses across the US, thousands of women join sororities every year through a structured recruitment process -- the sorority rush. Although these sisterhoods provide college women with opportunities for personal growth and enrichment, they have been criticized for their potential to lead their members to focus excessively and unhealthily on their appearance.

Rolnik's study is the first to test objectification theory (which links self-objectification to body dissatisfaction and shame, eating disorders and associated behaviors) outside the laboratory in a real-life context. They surveyed 127 first-year college women aged 17-20 years at a US Midwestern University to investigate the relationship between participation in a sorority rush, self-objectification, and eating disorder behaviors. The students were split into two groups: those who went through the recruitment process and joined the sorority, and those who did not take part in any aspect of the rush. At four different time points (before the rush; a few days into the rush; on the day the bids to join are received; and one month after the rush), participants completed online questionnaires.

Levels of self-objectification and disordered eating behaviors were higher among rush participants than among women who did not take part, throughout the study period. A month after the rush, new members also displayed higher levels of body shame. Those women with higher body weights were more likely to drop out of the rush process and feel dissatisfied with it, even though those who dropped out were not overweight but simply less thin than those who joined the sorority. These findings suggest that sorority membership may exacerbate pre-existing, problematic attitudes and behaviors.

The authors conclude: "Interventions aimed at reducing sorority women's focus on physical appearance may hold promise as one of the many routes to addressing body image disturbance and eating disorders among sorority members. As sororities are very powerful at influencing the norms and ideals of their members, a move away from a focus on appearance and towards a set of norms that encourages healthy eating habits and more positive approaches to body image has real potential."