Is obesity un-American? Disease concerns bias implicit perceptions of national identity

Abstract

The current research examined whether Americans incorporate obesity into their national identity, and further investigated the role an evolved behavioral immune system plays in shaping Americans' perceptions of obesity and national identity. Two studies revealed that obesity is not, on the whole, incorporated into the American identity at an implicit level. Moreover, when disease concerns were salient, either because of an experimental priming manipulation (Study 1) or due to recent illness (Study 2), thin individuals (for whom obesity may represent a particularly atypical morphology and thus a heuristic cue to disease) implicitly excluded obesity from the American identity to a greater degree. Thus, implicitly categorizing a subgroup of people as an outgroup pathogen threat may promote behavioral avoidance, exclusion, or stigmatization. This behavioral avoidance, could, in turn lead to less risk of fitness-reducing disease contraction. Further implications for evolutionary theories of disease avoidance, group identity, and discrimination are discussed.

Introduction

Approximately two-thirds of the United States population is overweight or obese (Flegal, Carroll, Ogden, & Curtin, 2010), and this fact appears not to have escaped the public's attention, as indicated by the increasing popularity of reality television shows such as The Biggest Loser, More to Love, and Fat Actress. Such trends thus provoke the question—is it that to be American is to be obese?

The current research proposes that, despite the increasing prevalence of obesity in American society, Americans nonetheless exclude obese individuals from their implicit national identity. Social cognition is guided in part by fundamental motives designed to help people overcome challenges recurrently faced throughout evolutionary history (Kenrick, Neuberg, Griskevicius, Becker, & Schaller, 2010), including the recurrent adaptive challenge of avoiding contagious diseases. A fundamental motivation for disease avoidance may promote the implicit exclusion of obese individuals from one's national identity.

People tend to include and exclude specific subgroups from their mental representation of the superordinate group (Devos and Banaji, 2005, Devos et al., 2010, Devos and Ma, 2008). An evolutionary perspective provides a useful framework for understanding why certain subgroups of individuals may be included or excluded from a superordinate group identity. Throughout history, other people have afforded both opportunities and threats relevant to fundamental survival and reproduction-relevant social goals (Neuberg & Cottrell, 2008). For example, contact with other people can provide opportunities for building prosocial alliances. However, it can also threaten fundamental goals related to survival (e.g., people are a common source of physical violence and communicable diseases). Consequently, many psychological processes are sensitive to characteristics of others that imply potential opportunities or threats (Maner, Miller, Moss, Leo, & Plant, 2012). The ascription of group identity may be one such psychological process. When forming mental representations of their group, people may include others who offer beneficial opportunities (thereby increasing the probability of interacting with those others) and exclude others who represent costly threats (thus promoting avoidance of those threats). Contagious disease may be one threat that shapes the ascription of group identity in this way.

The contraction of a communicable disease often requires close contact with pathogen carriers. Evolutionary perspectives suggest that, as a consequence, people are equipped with a psychological system designed to promote the avoidance of potential pathogen carriers—a sort of behavioral immune system (Neuberg et al., 2011, Schaller and Park, 2011). Indeed, when pathogen concerns are made salient, people respond to the presence of heuristic disease cues with a range of affective, cognitive, and behavioral reactions that promote a distancing of oneself from potential sources of disease (Ackerman et al., 2009, Curtis et al., 2004, Miller and Maner, 2011, Miller and Maner, 2012, Schaller and Duncan, 2007).

People may attempt to avoid pathogen carriers via social exclusion and avoidance of groups heuristically associated with disease (Navarrete and Fessler, 2006, Navarrete et al., 2007).

Of particular relevance to this study, implicit exclusion of a subgroup from the mental representation of a superordinate group has downstream effects on actual discriminatory and avoidant attitudes toward members of that subgroup (Yogeeswaran & Dasgupta, 2010). Thus, implicitly categorizing a subgroup of people heuristically perceived as a pathogen threat as an unfamiliar outgroup may promote behavioral avoidance, exclusion, or stigmatization. This behavioral avoidance, could, in turn lead to less risk of fitness-reducing disease contraction. Thus, people's mental representations of shared group membership can have actual consequences for behavior and fitness.

Pathogens themselves are invisible to the naked eye, yet they often produce visible morphological irregularities. Thus, many morphological irregularities can serve as heuristic cues of underlying pathogenic infection. Because obese individuals display morphological abnormalities (e.g., a highly exaggerated midsection), they may be (mis)perceived as pathogen carriers (Crandall et al., 2009, Harvey et al., 2002, Lieberman et al., 2012, Miller and Maner, 2012, Neel et al., 2013, Park et al., 2007, Park et al., 2013). Consistent with this perspective, adults (Lieberman et al., 2012, Oaten et al., 2009), and young children (Klaczynski, 2008) display disgust reactions toward the obese. When primed with disease concerns, people also display a range of processes that facilitate the avoidance of, or prejudice toward, obese others (e.g., Miller and Maner, 2012, Park and Isherwood, 2011, Park et al., 2007). Moreover, although anti-fat prejudice is observed among both thin and obese observers, thin individuals—individuals that likely view obesity as a more substantially atypical morphology—exhibit a greater degree of prejudice (Schwartz, Vartanian, Nosek, & Brownell, 2006).

We tested three primary hypotheses:

• Because obesity is a heuristic cue to disease, we predicted that obese individuals would be excluded from people's implicit representations of superordinate group identity.

• This effect would be apparent primarily among thin participants, for whom obesity is especially morphologically atypical.

• The effect among thin participants would be exacerbated when disease concerns are especially salient.

In two studies, we tested these three hypotheses by examining whether Americans implicitly exclude obese individuals from their national identity. In Study 1, we manipulated disease concerns via experimental priming methodology. In Study 2, we capitalized on natural variation in the salience of disease caused by recent illness.