Waist-to-Hip Ratio and Attraction

Basis for Attractiveness of Waist-to-Hip Ratio

A straightforward test of this evolutionary explanation would be to identify a feature of the body known to be linked with health and reproductive capability and to demonstrate that systematic variation in that feature produces systematic changes in judgment of female attractiveness. Body fat distribution as measured by waist-to-hip ratio (WHR) may be an ideal feature. First, WHR, unlike overall body weight, is an unambiguous indicator of age in men and women. Before puberty, both boys and girls have WHR in the range of .95 to .98 because body fat distribution is essentially similar in both sexes. However, during puberty, both men and women experience reduction in the size of their WHR. Increases in womens sex hormones induce an increase in pelvic width and regulate the anatomical location of body fat deposits. Simply stated, estrogen selectively inhibits fat deposits in abdominal and waist regions and facilitates fat deposits in the buttocks and thigh regions in women. Testosterone, on the other hand, inhibits fat deposits in buttocks and thighs, and facilitates fat deposition on the waist and upper body in men. After puberty, healthy women have a WHR between 0.67 and 0.79, whereas healthy men have a WHR between 0.8 and 0.95. As women age and their production of estrogen decreases, their WHR moves into the male range. Thus, WHR reliably signals the [Page 1680]reproductive age of the female unlike any other observable body feature.

Second, WHR is a reliable indicator of reproductive capability of women. Compared with women with high WHR, women with low WHR have fewer irregular menstrual cycles, optimal sexhormone profile, and ovulate more frequently. Low WHR is also an independent predicator of pregnancy in women participating in artificial insemination. Third, women with low WHR have lower risks for diseases that manifest in later adulthood, such as heart diseases, stroke, breast, endometrial, and ovarian cancers. Women less susceptible to health problems would likely have more energy to attend to their family and children and, as many health problems are inheritable, their offspring would receive the genetic gift of good health.

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