Time for T and Macho Men?  

People tend to think that their face preferences—the types of faces that they consider to be particularly attractive—do not really change much over a matter of days or weeks. However, our study, recently published in the journal Hormones and Behavior, found that the extent to which women find masculine faces attractive might be closely linked to changes in their testosterone levels.

Many different aspects of women’s behavior change systematically during the menstrual cycle. For example, women are more likely to have sex during the late follicular phase of the menstrual cycle when they are at their most fertile, than during the luteal phase of the cycle when fertility is relatively low.

Previous studies have found that women also demonstrate stronger attraction to masculine characteristics in men when they are most fertile. Masculinity in men’s faces signals some positive characteristics, such as a healthy immune system that may be inherited by offspring, and some negative characteristics, such as less interest in caring for children. Consequently, changes in women’s preferences for masculine men during the menstrual cycle may help women maximize the possible benefits of their mate choices. In other words, they favor “caring and sharing” feminine men generally, but desire slightly healthier and more masculine men when they are most likely to conceive.

While it is very well established that women’s preferences for masculine men are enhanced during the late follicular phase of the menstrual cycle (around ovulation), the hormonal changes that contribute to these shifts in attraction are unclear. Our study compared the effects of changes in women’s testosterone, estrogen, and progesterone levels during the menstrual cycle on masculinity preferences.

Examples of stimuli used in our study. Left: masculinized version. Right: feminized version.

Seventy women were tested once a week over a period of a month. None of these women were pregnant or using hormonal contraceptives. On each occasion the women in our study provided a saliva sample and completed a short face preference test. In the face preference test the participants were shown a series of pairs of faces, each pair consisting of a feminized version (with, for example, large eyes and a round jawline) and a masculinized version (with, for example, a square jawline and a wide nose). They were asked which version in each pair was the more attractive.

When we compared these choices in the test sessions with the highest and lowest testosterone levels, we found that attraction to the masculinized versions was stronger when testosterone levels were high (around ovulation) than when testosterone levels were low (closer to the onset of menses). This suggests that women’s face preferences may be closely linked to their testosterone levels, a hormone that varies systematically over the menstrual cycle by slowly increasing from menstruation to mid-cycle (ovulation) and then slowly declining again. Similar comparisons of sessions with the highest and lowest progesterone levels or the highest and lowest estrogen levels did not show such a striking difference, suggesting that these hormones may not affect masculinity preferences.

Changes in women’s testosterone levels appear to be important for a variety of sexual and social behaviors. Our findings add to this literature by demonstrating a link between testosterone levels and the strength of women’s attraction to masculine men. We are currently carrying out further studies to investigate if changes in women’s testosterone levels over the course of a day and over the course of a year have similar effects.

Our findings for a link between women’s testosterone levels and their preferences for masculine men highlight possible hormonal reasons for attraction to different types of men. Thus, the extent to which women find “macho” men attractive could reflect their testosterone levels.

Lisa Welling is a postgraduate research student and Ph.D. candidate in the Face Research Laboratory at the University of Aberdeen.