Assessing the roles of symmetry, prototypicality, and sexual dimorphism of face shape in health perceptions

Health perceptions are thought to play an important role in human mate preferences. Although many studies have investigated potential relationships between health ratings of faces and facial symmetry, prototypicality, and sexual dimorphism, findings have been mixed across studies. Consequently, we tested for potential relationships between health ratings of faces and the symmetry, prototypicality, and sexual dimorphism of those faces' shapes. When these three shape characteristics were considered in separate regression models, we observed significant positive relationships between health ratings and both shape symmetry and prototypicality. By contrast, health ratings and sexual dimorphism were not significantly correlated in these analyses. However, in analyses in which symmetry, prototypicality, and sexual dimorphism were entered simultaneously as predictors in a single model, prototypicality, but not symmetry, was significantly correlated with health ratings. Moreover, sexual dimorphism predicted health ratings of female, but not male, faces in these analyses. Collectively, these results suggest that the relationship between symmetry and health ratings is, at least partly, driven by the effect of prototypicality on health perceptions and highlight the importance of considering multiple aspects of face shape when investigating factors that predict perceived health.