Re-examination of chewing and spitting behavior: characteristics within and across eating disorder diagnoses.

Chewing and spitting (CS) out food is a relatively understudied eating disorder behavior. The aim of this study was to examine lifetime and current frequencies of CS across eating disorder diagnostic groups and to compare the severity of eating disorder symptomatology between participants who did and did not endorse CS. A total of 972 individuals presenting for outpatient eating disorder treatment between 1985 and 1996 completed a questionnaire that included items regarding current and lifetime eating disorder behaviors, including CS. Results indicated that both lifetime and current prevalence estimates of CS varied cross-diagnostically, with CS being more common among those with anorexia nervosa and bulimia nervosa compared to those with eating disorder not otherwise specified. CS was significantly associated with several eating disorder symptoms, including compensatory behaviors, meal restriction, and lower BMI. Those who reported CS were also younger in age compared to those who did not report CS. These findings indicate that CS is associated with more severe eating and weight pathology and is not equally prevalent across eating disorder diagnoses. These results also support the relatively high occurrence of CS and the importance of targeting this behavior in eating disorder treatment. Future research should clarify the correlates, mechanisms, and function of CS in eating disorders.