Researchers in Finland have found that women’s preference for male body hair appears to change across the menstrual cycle.
“These findings suggest that body hair may play a much more important role in human mate choice than previously thought and that biological factors, such as hormones and sexual imprinting or heritable preferences, may explain individual variation in women’s preferences with regard to body hair,” researchers Markus J. Rantala, Mari Pölkki and Liisa M. Rantala wrote in their study.
The research was published in the journal Behavioral Ecology.
The researchers from the University of Turku photographed 20 men, aged 20–32 years, with visible chest and torso hair before and after they shaved themselves clean. Rantala and his colleagues then interviewed 552 heterosexual women, asking them to choose between the hairy and shaved versions of the same body.
“Interestingly, we found that the removal of body hair increased the sexual attractiveness of the male body to Finnish premenopausal women,” the researchers explained. This was especially true for younger fertile women, who preferred the shaved body more than the hairy body.
Rantala and his colleagues also found that women in the non-fertile phase of their menstrual cycle were more likely to prefer male body hair than women in the fertile phase. Pregnant women and postmenopausal women were also more likely to prefer male body hair.
“The finding that menstrual cycle, pregnancy, and menopause have effect on women preference on body hairs is a strong argument against the interpretation that change in fashion would explain why older women preferred more hairy men,” the researchers said. “Rather, it suggests that sex hormones might have effect on preferences.”
The hairiness of a woman’s father was also associated with her preference for male body hair.
“This suggests either that women are sexually imprinted for the hairiness of their father or that women’s preference for body hair is heritable,” the researchers said.
However, the Rantala and his colleagues acknowledged that body hair itself might not be the physical trait that women are “cueing in on.”
“For example, body hair could mask desirable male traits like muscles and a v-shaped body, which women found more attractive during the fertile phase of their menstrual cycle (see Little et al. 2007), and shaving body hair makes these traits more visible,” they said.
It is also possible that hairless bodies are associated with a particular type of man.
“On the other hand, in contemporary Finland, body hair may be a signifier (positive or negative) of some target of learned prejudice: social class, ethnic background, etc,” the researchers wrote, noting that Scandinavian men tend to have less body hair than men from other parts of the world.
“Clearly, more experimental studies are needed to show whether changes in women’s preferences on body hairs with menstrual cycle are widespread among different human cultures before any generalization can be made.”
