RESUMEN
The Three-Factor Eating Questionnaire (TFEQ) is one of the most widely used instruments to study different eating behaviors. It measures three types of eating behaviors namely: cognitive restraint, uncontrolled eating and emotional eating. The present study aims to evaluate the factor structure and reliability of the Portuguese version of the TFEQ-R21, using a confirmatory factor analysis (CFA). The sample includes 468 participants from the general population, with ages ranging from 18 to 60 years. Results from the CFA confirmed the TFEQ-R21 three-factor structure and the model revealed an acceptable fit to the data (χ2(186) = 443.211, p < 0.001; χ2/df = 2.329; CFI = 0.933; TLI = 0.925; RMSEA = 0.054; SMRS = 0.053). Multi-group analysis results support strong measurement invariance across genders. Furthermore, all three dimensions presented adequate psychometric properties. Overall, results support that the Portuguese version of the TFEQ-R21 is a useful, reliable and robust instrument to assess relevant eating behaviors.Level of evidence V, descriptive studies.