Cognitive dietary restraint and cortisol: importance of pervasive concerns with appearance.

The purpose of this study was to elucidate the nature of the relationship between dietary restraint and physiological stress, by investigating which eating and body-related constructs are related to salivary cortisol and to perceived stress. Female undergraduates (N = 170) completed self-report measures on dietary restraint, appearance beliefs, body satisfaction variables, perceived stress, and eating self-efficacy. Participants also provided two saliva samples. The first sample was collected after awakening, and the second was collected 6-8 h later. A factor analysis was performed in order to reduce redundancy in the set of measures surrounding eating and body attitudes, which yielded three factors. The findings indicated that women with stronger beliefs about the importance of their appearance, as well as negative emotions and cognitions surrounding their body image, had higher levels of cortisol in the afternoon. These appearance and body-related constructs were also associated with higher levels of perceived stress. However, perceived stress was not associated with salivary cortisol. There were no significant relationships between any of the eating or psychological variables and morning cortisol levels. These results suggest that dysfunctional cognitions surrounding appearance and body image significantly contribute to the relationship between dietary restraint and elevations in cortisol excretion. Implications for interventions and women's health are discussed.