Hourglass Figures and Gender Equality
Attempting to explain why women have larger waist-to-hip ratios, especially in Europe and North America, Elizabeth Cashdan and her team analysed data from 33 non-Western populations and 4 European populations. They examined this in conjunction with the 'ideal' waist-to-hip ratio for women.
The 'ideal' refers to both what is medically ideal and what is most desired by men. According to medical studies a 'curvy' waist-to-hip ratio of 0.7 or lower is associated with higher fertility and lower rates of chronic disease. Studies have also shown that men prefer a ratio of 0.7 or lower when looking for a mate. The preference makes perfect sense, according to evolutionary psychologists, because the low ratio is a reliable signal of a healthy, fertile woman.
The study concludes that there is a relationship between androgens and effective stress management. Androgens, a class of hormones that includes testosterone, increase waist-to-hip ratios in women by increasing visceral fat, which is carried around the waist. Increased androgen levels are also associated with increased strength, stamina, and competitiveness. Cortisol, a hormone that helps the body deal with stressful situations, also increases fat carried around the waist.
So while it may increase women's waistlines, it also helps them be more competitive and deal with stressful contexts. The study contends that there is a correlation between lower levels of women's economic independence in Japan, Greece and Portugal, and the fact that men place a higher value on a thin waist than men in Britain or Denmark, where there tends to be more sexual equality. And in some non-Western societies where food is scarce and women bear the responsibility for finding it, men actually prefer larger waist-to-hip ratios.
The global differences may reflect therefore evolutionary needs. According to the authors of the study, the different 'ideal' waist-to-hip ratio depends on the degree to which men want their partners to be "strong, tough, economically successful and politically competitive."