Background: Despite the stigma attributing obesity to a lack of willpower, research on the interrelationships among an individual's willpower, eating behaviors, and obesity is lacking. Objective: This study aimed to quantify the extent to which multidimensional eating behaviors mediated the association between obesity and grit, which share commonalities with self-control. Methods: This cross-sectional study involved Japanese adults across a wide range of age groups. Grit was measured using an 8-item short grit scale. Multidimensional eating behaviors were measured using the Japanese version of the 21-item Three-Factor Eating Questionnaire-R21, comprising uncontrolled eating, emotional eating, and cognitive restraint. Obesity was defined as a body mass index ≥25.0 kg/m2, which is the World Health Organization's cutoff specific to Asian populations in the Asia-Pacific region. A series of logistic regression models were created to analyze the association between grit and obesity with and without eating behaviors. Mediation analyses using the Karlson Holm Breen method were performed to determine whether eating behavior mediated this association. Results: Of the 1641 adults, 26.8% were obese. A higher grit level was associated with a lower likelihood of obesity, less uncontrolled and emotional eating, and higher cognitive restraint. Uncontrolled and emotional eating fully mediated the association between grit and obesity, whereas cognitive restraint only partially mediated this association. Conclusions: The inverse association between grit and obesity was mediated by multidimensional eating behaviors. Identifying impairments in eating behaviors, rather than focusing on an individual's lack of willpower, may contribute to dispelling the aforementioned stigma and facilitating a dialogue for the prevention and management of obesity.

The authors have declared no competing interest.

This study was supported by JSPS KAKENHI (Grant Number: JP22H03317). The funder (Japan Society for the Promotion of Science) had no role in the study design; collection, analysis, and interpretation of data; and writing of the report, and there are restrictions regarding publication.

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This cross-sectional online survey was approved by the Institutional Review Board at Fukushima Medical University (ippan2022-210).

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