Are dietary restraint scales valid measures of moderate- to long-term dietary restriction? Objective biological and behavioral data suggest not.

Prospective studies indicate that elevated scores on dietary restraint scales predict bulimic symptom onset, but experiments indicate that assignment to dietary restriction interventions reduces bulimic symptoms. One possible explanation for the inconsistent findings is that the dietary restraint scales used in the former studies are not valid measures of dietary restriction. The authors previously found that dietary restraint scales were not inversely correlated with objective measures of short-term caloric intake (E. Stice, M. Fisher, & M. R. Lowe, 2004). In this follow-up report, 3 studies indicated that the Three-Factor Eating Questionnaire dietary restraint scale was not correlated with doubly labeled water estimated energy intake over 2-week periods or with observationally measured caloric intake over 3 months. Results from this study and others suggest that dietary restraint scales may not be valid measures of moderate- to long-term dietary restriction and imply the need to reinterpret findings from studies that have used dietary restraint scales.