The Effects of Resource Scarcity on the Ideal Female Body Size

When it comes to women’s body ideals, is it true that thin is in? Or is shapely sexy? The answer to this question varies considerably across cultures. Although ultra-thin female models are idealized in Western nations like the United States, individuals living in nations where resources are scarce, tend to prefer women with a heavier body size (see e.g., Swami et al., 2010). This pattern repeats itself within nations, communities, and across the sexes. People living in relatively safe, affluent regions idealize thinner female bodies than those residing in more dangerous, lower SES communities (Swami et al., 2010). Resource scarcity and stress also increase the heaviness of the body that men most desire in their romantic partners (Swami & Tovée, 2012), but not necessarily themselves (Sobal & Stunkard, 1989). Why do researchers regularly observe a relationship between resource scarcity and preference for a heavier female body ideal? Here, we use insights from two theoretical models in evolutionary biology – life history theory and the critical fat hypothesis – to examine whether this relationship might emerge from the different life history strategies typically adopted by individuals living in resource scarce versus resource plentiful environments. Female body fat plays a key role in women’s fertility regulation, with thinness being related to suboptimal fertility (Frisch, 1985). Accordingly, we predicted that resource scarcity cues– which promote the contingent expression of a faster life history strategy and more immediate reproduction – would produce a preference shift away from the very thin, sub-fertile female ideal typically chosen by Western women toward a heavier, more fertile female form.