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Updated: May 20, 2026

Errors as a Means of Reducing Impulsive Food Choice
Published on: June 5, 2016
An exploratory study on portion size estimation errors: psychological correlates of portion size estimation errors in
Mayron Piccolo1,2,3, Tanya Tandon4, Dany Laure Wadji5
1Department of Psychology, Harvard University, William James Hall 844, 33 Kirkland Street, Cambridge, MA, 02138, USA. mpiccolo@fas.harvard.edu.
Purpose:
Accurate perception of food portion sizes is implicated in healthy eating, yet little is known about psychological correlates of portion estimation in non-clinical, normal-weight adults. This exploratory study examined whether consumption intent (self vs other) and markers of psychological processes associated with eating (dietary restraint, shape/weight overvaluation, body dissatisfaction) are associated with portion size estimation errors, and whether these errors relate to body mass index (BMI).
Methods:
Seventy-one adults (BMI 18.5-24.9 kg/m2) without current or past psychiatric disorders were included. Eating psychopathology was assessed using the brief 7-item, 3-factor version of the Eating Disorder Examination Questionnaire (Dietary Restraint, Shape/Weight Overvaluation, Body Dissatisfaction). Portion estimation was measured with the Portion Estimation Task, with images rated on a visual analog scale (0-100) under two conditions: general intent (for others) and intent-to-eat (for self). A proportional estimation error index was calculated across all non-full portion sizes relative to each participant's full-portion reference. A linear mixed model tested the effect of intent and Pearson correlations examined the association with psychological variables and BMI.
Results:
Consumption intent did not influence portion size estimation (p = 0.989), so conditions were combined. Estimation Error Indices were positively correlated with Dietary Restraint (r(69) = 0.27, p = 0.021), but not with Shape/Weight Overvaluation or Body Dissatisfaction. BMI correlated with Shape/Weight Overvaluation and Body Dissatisfaction, but not with Dietary Restraint or the Estimation Error Index.
Conclusion:
In normal-weight adults without eating disorders, greater dietary restraint is associated with larger biases in portion size estimation, whereas BMI and body-related evaluative concerns primarily track weight status rather than perceptual errors in portion size estimations. Findings are exploratory and warrant replication in larger, more diverse samples.
Level Of Evidence:
III. Evidence obtained from well-designed cohort or case-control analytic studies.
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