OBJECTIVE: To identify the factors associated with an adequate perception of body image in relation to body weight. MATERIAL AND METHODS: An observational, cross-sectional study was conducted in a representative sample of the European Union (7,155 men and 8,077 women). Body Mass Index (BMI) was grouped into four categories, perceived body image was assessed using the nine silhouettes drawing scheme. A multivariable logistic regression model for each sex was used to adjust for potentially confounding variables. RESULTS: Underweight men and women classified themselves better than other groups (92.9% of correct answers among men and 79.3% among women). Overall, women classified themselves better than men (57.6% vs. 32.7%). DISCUSSION: Perceived body image as a method of assessment for body weight has different validity depending on sociodemographic or attitudinal categories. Perceived body image as an estimate of the nutritional status has a limited individualized application. Thus, perhaps it could be applied as a proxy measure of adiposity among slim males and among slim and overweight females, but not among the other groups.