Over cocktails this week, my girlfriends and I got into a discussion about grooming. We first compared notes on our preferred “wax specialists” who have been keeping our bikini hair lines nice and neat for our pool and beach excursions. We then started talking about the men in our lives and found considerable variation in opinion as to whether manscaping (the trimming or shaving of genital hair) is desirable. This got me thinking about why we each differed so much in our preferences. Anthropologists have documented that the removal of body hair from the neck down (called body depilation) was socially desirable in Egyptian and Greek cultures,1 but the presence of back, buttocks, and genital hair has been (and remains) associated with masculinity and fertility for men in other cultures.2
So how much body hair do women prefer? Well, as is often the case…it depends. The late Charles Darwin actually proposed that because humans differ greatly in their preference for different amounts of body hair, this then led to population differences across the world in “hairiness” of bodies.3 In China, for example, women rate men with little or no chest hair as most attractive, whereas women in England and Sri Lanka rate male body hair positively.4Darwin’s proposal means that when a man matches a woman’s preferred amount of body hair, he is more likely to hook up with her, making him “reproductively successful.” His genes carry on to a new generation; over time, we then see variability in how hairy men are across different groups.
A considerable amount of research has shown that women prefer more masculine traits (e.g., facial masculine traits like a strong jawline) when they are ovulating (and most fertile), but prefer less masculine traits (e.g., signs of less aggressive behaviors) when they are less fertile.5 Scientists believe that this change in preference is adaptive, as strongly masculine traits may signal that the man has good genes. Comparatively, less masculine traits signal that the man would invest more and be a supportive caretaker and parent. Therefore, when a woman is fertile, signs of “good genes” are preferred; when she is less fertile, then signs of being a good parent are desirable.
But does research actually support the historical belief that body hair is associated with masculinity? Recent research suggests the opposite. New fathers have been shown to have heightened levels of estradiol, which can result in greater body hair, rather than less.4Estradiol is a sex hormone that is associated with fertility; when men have greater levels of it, they tend to be less fertile. Body hair in this case would signal “good parent” rather than “good genes.” In addition, a number of recent studies have found that women’s preferences for their sexual partner’s body hair change over the course of their menstrual cycles. For example, when heterosexual Finnish women were fertile, an experiment found that they rated hairless male bodies as more attractive than when they were not fertile; post-menopausal and pregnant women actually preferred hairier bodies.4
My group of happy hour friends no doubt varied in preference for male body hair due to all of us being from very different cultures. For example, my Australian friend, Hope, prefers hairy chests that she can “cuddle up” with and run her fingers through, whereas my Chinese friend Jia Li was repulsed by that idea. I don’t care so much about chest hair, but back and buttocks hair are not appealing at all. Some evidence suggests that pubic hair removal increases male sensitivity and appearance of size,6,7 and this has been used to explain why shaving or eliminating male body hair has been commonly reported among many men today.8 Despite the great variability in upper body hair preferences, my girlfriends and I agreed on one thing: giving oral pleasure without getting hair in our mouths was the reason we all prefer manscaped men.