Men may fancy it and medical science considers it the best indicator of a woman's health and fertility, but the classic hourglass figure isn't necessarily suited for demands in the real world, according to new body type research conducted at the University of Utah.

Having a less than Barbie doll, more cylindrical body might not look ideal on the shelf, but it offers substantial benefits for coping with daily life, Elizabeth Cashdan, chair of the U. anthropology department, reports in the December issue of the journal Current Anthropology.

In societies and under conditions in both Third World and industrialized countries, women with bigger waists and flatter hips tend to have the strength, assertiveness and competitive attributes to cope with the stresses of bringing home the bacon and tending to the survival of her family.

The ancient ideal proportion, according to research at Utah State University, the hips roughly a third larger than the waist reflects, a hormonal balance that results in women's preferentially storing fat on their hips as opposed to their waists. That type correlates with higher fertility and resistance to disease.

Cashdan writes that the profile is an hourglass by design but it tends toward an apple in function. In other words, the classic female shape, which Cashdan assigns a waist-to-hip ratio (WHR) of 0.7 — the lower the number, the more pronounced the curves — may be the medical and social standard, but most women in the real world have a WHR of 0.8, she said.

An 0.8 is still within the ideal range for women, according to recent nutrition research at USU. For men, 0.95 or less is ideal. The WHR is calculated by dividing your waist measurement by your hip measurement.

Cashdan's said her research aimed to address the disparity between the ideal and the real: If 0.7 is the magic number both in terms of health and male mate choice, why are most women significantly higher?

The answer appears to be hormonal. 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. A synthetic form of it is used by athletes to enhance performance. Cortisol, a hormone that helps the body deal with stressful situations, also increases fat carried around the waist.

"The hormonal profile associated with high WHR may favor success in resource competition, particularly under stressful circumstances," writes Cashdan. "The androgenic effects — stamina, initiative, risk-proneness, assertiveness, dominance — should be particularly useful where a woman must depend on her own resources to support herself and her family."