When does behavior follow intent? Relationships between trait level dietary restraint and daily eating behaviors.

BACKGROUND: The relationship between self-report trait level restriction and daily engagement in restriction behaviors is not well understood, and as a result the usefulness of such trait level measures is unclear. The present study aimed both to examine the validity of self-reported trait dietary restraint behaviors, and to examine the respective relationships among self-reported trait dietary restraint intentions and behaviors and both restrained and disinhibited eating at the daily level. METHODS: A sample of 109 women (Mage = 24.72, SD = 4.15) completed a self-report trait level measure of dietary restraint before providing EMA data on their daily engagement in dietary restraint and disinhibited eating behaviors, as well as mood, over a period of 7 days. Multilevel hurdle models were used to test the relationship between trait levels of dietary restraint, and daily level reports of restraint and disinhibited eating behaviors. RESULTS: Trait restraint behavior was a consistent predictor of daily presence and frequency of restraint behaviors. In contrast, trait restraint intentions was not a predictor of daily restraint behaviors, however it did predict daily frequency of overeating. In addition, daily negative affect emerged as a predictor of comfort eating, but was not predictive of restraint behaviors. CONCLUSIONS: Findings confirm the usefulness of assessments of self-reported trait dietary restraint behaviors as a method of capturing dieting behaviors. In contrast, trait level dietary restraint intentions was a poor predictor of eating outcomes and more research on the way that restraint intentions affect eating behaviors is warranted.

Understanding the link between body image and binge eating: a model comparison approach.

PURPOSE: The present study tests several competing, explanatory models-dual pathways, escape from awareness, and objectification theory-for the established link between body dissatisfaction and binge eating. METHODS: 408 women aged between 18 and 40 years completed a survey designed to assess contributions of proposed mediators (dietary restraint and negative affect from the dual pathway model, self-distraction from the escape from awareness model, and interoceptive deficits from objectification theory) for the body dissatisfaction-binge eating relationship. RESULTS: Although mediation analyses supported the dual pathway model and objectification theory when tested separately, the dual pathway model most strongly predicted the body dissatisfaction-binge eating relationship. Both model-implied mediators (dietary restraint and negative affect) made significant unique contributions, accounting for roughly one-quarter of the shared variance between body dissatisfaction and binge eating when tested separately from other mediators. Improvements in variance explained were negligible once other proposed mediators were included in a test of models combined. CONCLUSIONS: Collectively, these findings suggest the superiority of the dual pathway model over objectification theory and the escape model, but the remaining unaccounted for covariance suggests need to consider alternative mechanisms that may also account for the relationship between body dissatisfaction and binge eating.

Optimizing prediction of binge eating episodes: a comparison approach to test alternative conceptualizations of the affect regulation model.

BACKGROUND: Although a wealth of studies have tested the link between negative mood states and likelihood of a subsequent binge eating episode, the assumption that this relationship follows a typical linear dose-response pattern (i.e., that risk of a binge episode increases in proportion to level of negative mood) has not been challenged. The present study demonstrates the applicability of an alternative, non-linear conceptualization of this relationship, in which the strength of association between negative mood and probability of a binge episode increases above a threshold value for the mood variable relative to the slope below this threshold value (threshold dose response model). METHODS: A sample of 93 women aged 18 to 40 completed an online survey at random intervals seven times per day for a period of one week. Participants self-reported their current mood state and whether they had recently engaged in an eating episode symptomatic of a binge. RESULTS: As hypothesized, the threshold approach was a better predictor than the linear dose-response modeling of likelihood of a binge episode. The superiority of the threshold approach was found even at low levels of negative mood (3 out of 10, with higher scores reflecting more negative mood). Additionally, severity of negative mood beyond this threshold value appears to be useful for predicting time to onset of a binge episode. CONCLUSIONS: Present findings suggest that simple dose-response formulations for the association between negative mood and onset of binge episodes miss vital aspects of this relationship. Most notably, the impact of mood on binge eating appears to depend on whether a threshold value of negative mood has been breached, and elevation in mood beyond this point may be useful for clinicians and researchers to identify time to onset.

Improving prediction of binge episodes by modelling chronicity of dietary restriction.

This study evaluates the influences of chronicity of, and time lag between, dietary restriction and binge outcome for predicting binge episode onset. Sixty-two women aged 18 to 40 years old completed an online survey at random intervals seven times daily for a 7-day period. Participants self-reported engagement in dietary restriction and/or binging, and temptation to binge. Consecutive instances of reported dietary restriction better predicted subsequent binges than single instances. As the time lag between the first report of dietary restriction and binge onset increased, a clear linear trend emerged, such that the value of restriction for predicting binges increased with the number of consecutive assessments in which they reported dietary restriction. A similar pattern was found when predicting temptation to binge. Present findings suggest that duration of restriction is a crucial determinant of binge onset. These findings have implications for clinical practice by highlighting the time course from dietary restriction to binging.

Tests of an extension of the dual pathway model of bulimic symptoms to the state-based level.

The dual pathway model proposes that trait body dissatisfaction leads to bulimic symptoms via two distinct pathways: dieting and trait negative affect. As many of these modelled variables have state-based equivalents, the present study evaluated the generalisability of this model to predict associations between state body dissatisfaction and instances of disordered eating. 124 women aged 18 to 40 years completed an online survey (accessed via a mobile phone device with web access) over a 7-day period. The mobile phone device prompted participants at random intervals seven times daily to self-report their state body dissatisfaction, current mood experiences, dieting attempts, and disordered eating practices. Multi-level mediation modelling revealed that both negative mood states and dieting significantly mediated the state body dissatisfaction-disordered eating relationships, although the strength of these associations depended on the aspect of disordered eating measured and individual differences in trait body dissatisfaction, internalization of appearance standards, tendency towards dieting, and BMI. Collectively, these results not only support adapting the dual pathway model to the state-level, but also suggest that several of the model implied pathways may be more relevant for individuals with more pathological eating- and body-related concerns and behaviours.

Does the burden of the experience sampling method undermine data quality in state body image research?

Despite growing popularity of experience sampling methodology (ESM) for evaluations of state-based components of body image, there have been concerns that the frequent repeated measurement might encourage problematic responding resulting in low data quantity and/or quality. Using a sample of 105 women (mean age=24.84), this study used multilevel modelling to investigate whether (a) there were changes in compliance or response variability across a 7-day period, and (b) whether such changes are explained by participant characteristics. Present findings suggest that demands of ESM protocol undermine quantity more so than quality of obtained data. Decline in procedural compliance across the testing period correlated with BMI and body shame, whereas reduced variability in state-based assessments did not adversely impact the strength of association between state body satisfaction ratings and other variables in the dataset. The authors make several recommendations for ensuring the quality of ESM-based data in future studies.