Is the human face a biomarker of health? - A scoping review.

There is a widespread assumption that facial features could act as a biomarker of human developmental stability and thus provide an important cue to an individual's physical and mental health status. However, research to date shows mixed support for this assumption. This is the first review that explores the association between various aspects of health and facial features, namely symmetry, averageness, and sexual dimorphism in adults. We searched electronic databases including Web of Science, MEDLINE PubMed, Scopus, and Embase. We followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines for reporting of our results. Of the 702 screened articles, 21 were eligible for inclusion. Studies presented various relationships between facial features and cardiovascular health; immunocompetence; oxidative stress level; cortisol level; reproductive health; cognitive health, and general physical health. This review results in an inconclusive answer to the question of whether facial features can serve as honest indicators of health. The results warrant caution when utilizing facial features as a biomarker of health status and biological condition of an individual. Protocol: Open Science Framework, https://osf.io/dv9pu/.