Further evidence that facial width-to-height ratio and global facial masculinity are not positively associated with testosterone levels

Objectives Facial masculinity, as for example measured by the facial width-to-height ratio (fWHR) or the global facial masculinity index, has been associated with a vast  range of behavioural traits, including dominance and aggression. Further, facial masculinity is thought to be influenced by testosterone (T) levels as an underlying mechanism. However, a recent meta-analysis on fWHR and T levels provided non-significant associations in men, which we wanted to examine further in men and additionally in women. Methods We examined whether fWHR and global facial masculinity are positively associated with salivary baseline T and T reactivity in 140 men (age 18-34 years), as well as with salivary baseline T and hair T concentrations in 151 women (age 18-35 years). Results No associations of salivary baseline T, T reactivity or hair T levels with fWHR or global facial masculinity were observed. Additional analyses revealed sex differences in sexual dimorphism in fWHR and global facial masculinity: men had generally higher global facial masculinity compared to women, but unexpectedly a lower fWHR. Conclusions Overall, our results provide further evidence that neither fWHR nor global facial masculinity are related to T levels and question earlier findings on male-biased sexual dimorphism in fWHR.