New research has revealed that women with a "less than perfect" body shape can often be physically stronger and more resistant to stress than those with a low waist-to-hip ratio.
Hormones that make women stronger, more competitive and better able to withstand stress also move fat from the hips to the waist, leading to a more cylindrical body shape.
Elizabeth Cashdan, an anthropologist at the University of Utah, carried out the study, and was led to conclude that having a body that is not conventionally "perfect" could offer substantial benefits for women over those with the typical "hourglass" figure.
Her research found that women who go out to work and are involved in competitive stressful environments are less likely to have an hourglass body shape because of the hormones that kick in when they have to rely on their own resources.
The study also revealed that women in countries such as Japan, Greece and Portugal tended to be slimmer as they are less likely to be economically independent.
Professor Cashdan commented: "The hormonal profile associated with high waist-to-hip ratio may favour success in resource competition, particularly under stressful circumstances.
"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."