Dietary restraint is non-genetically associated with change in body mass index: the Healthy Twin Study

Emotional Eating as a Mediator in the Relationship between Dietary Restraint and Body Weight

This study aimed to assess the relationships between routine and compensatory restraints and body mass index (BMI), as well as to explore the mediating role of emotional and external eating in the relationships between routine and compensatory restraints and BMI. Chinese adults aged ≥18 years with different weight statuses were invited to fill out an online questionnaire. Routine and compensatory restraints and emotional and external eating were assessed using the validated 13-item Chinese version of the Weight-Related Eating Questionnaire. Mediation analyses tested the mediation effects of emotional and external eating on the relationship between routine and compensatory restraints and BMI. In total, 949 participants (26.4% male) responded to the survey (mean age = 33 years, standard deviation (SD) = 14, mean BMI = 22.0 kg/m², SD = 3.8). The mean routine restraint score was higher in the overweight/obese group (mean ± SD = 2.13 ± 0.76, p < 0.001) than in the normal weight (2.08 ± 0.89) and underweight (1.72 ± 0.94) groups. However, the normal weight group scored higher in compensatory restraint (2.88 ± 1.03, p = 0.021) than the overweight/obese (2.75 ± 0.93) and underweight (2.62 ± 1.04) groups. Routine restraint was related to higher BMI both directly (β = 0.07, p = 0.02) and indirectly through emotional eating (β = 0.04, 95% confidence interval (CI) = 0.03, 0.07). Compensatory restraint was only indirectly related to higher BMI through emotional eating (β = 0.04, 95% CI = 0.03, 0.07).