Body fat and facial shape are correlated in female adolescents

Relative body weight is not only an important indicator for health and reproductive condition, but also subject to stereotypes and stigmatization. It can be reliably assessed from adult faces alone, yet the facial correlates, especially in adolescents, remain largely unidentified. This study was designed to determine the facial features of adolescent girls that change with body fat proportion using a modern, comprehensive technique for shape analysis.

Standardized frontal facial photographs of 22 Caucasian female adolescents (mean age 15.8 ± 2.7 years) were taken, and body height, body weight, and body fat proportion measured. Seventy-two somatometric measurement points were digitized on each photograph and their Cartesian coordinates regressed onto body fat proportion. Geometric morphometrics also enabled visualizing the statistical results as shapes.

Body fat proportion explained 8.7% of the facial shape variation (10,000 permutations, P = 0.047). Girls with high body fat had a relatively rounder and larger lower face, relatively smaller eyes, and a shorter and wider nose, fuller lips and downturned corners of the mouth. Low body fat was associated with a more angular lower face and a pointier chin, relatively larger eyes and a longer nose. The lips were wider and thinner, the corners of the mouth upturned.

Body fat proportion is a substantial factor in facial shape variation of female adolescents. The potential influence of the corresponding facial features on social perception is discussed. Prospects for future research including novel possibilities for stimuli design (GM morphs) are highlighted.