Prevailing voices in the public and health sciences state that lower class people are much more likely to become “overweight” compared to their “middle” and “high class” counterparts. In this sense, the so-called “obesity epidemic” becomes inseparable from the discussion of class, and the equation remains clear: “the poor are fat and the fat are poor.”
In order to explain the link between class and body weight, people generally refer to two assumptions about poor people: they have less access to healthy food and they don’t know which food is healthy. Over the last decades, studies that explore the social determinants of health and illness in populations (“social-epidemiology”) have particularly discussed this relation between food and fatness as a class issue, further boosting the argument that poor people tend to demand and receive less healthy food. A second look at the aforementioned equation however (“the poor are fat and the fat are poor”) shows that social-epidemiological studies rather focused on the first part, asking why the poor are fat or why poor people become fat.
If we review the current social-epidemiological literature, it becomes more and more evident that the link between income and fatness can also be explained from a different perspective that does not rely on this “hypothesis of causation,” but explores the impact of body shape on social status. I want to argue that there is no clear evidence that lower income is related to a higher risk of fatness. Even more, current studies suggest that the relationship between income and fatness should be rather seen from an alternative perspective of “reverse causality.” It is our societal understanding of fatness that influences one’s opportunities and social positioning. In other words, we need to focus on the question if and why fat people can become poor.
In this post, I will first describe these two perspectives that can be used in analyzing income-related inequalities in fatness. Secondly, I will discuss the results of a recently published literature review to highlight how the link between income and fatness can be revisited in current social-epidemiology.
Class and Fatness in Traditional Social-Epidemiology
In the attempt to understand the triangle between class, food and fatness in health sciences, social-epidemiological studies refer to income, education as well as occupational status as general indicators to classify one’s social status. To explain why people with a lower social class are prone to ”obesity,” most studies conclude that poor people increasingly face health impairing social conditions such as a lack of access to healthy foods and medical care. Furthermore, lower class people are also accused of an (allegedly self-inflicted) lack of education and health literacy—knowledge about health promoting behavior and the ability to make the right choices. Those narratives tend to justify social inequality on the basis of an individual’s incapability (or even unwillingness) to achieve proposed societal goals—such as health. Class status is then perceived as the product of individual failure rather than a result of social inequalities.
This notion of a “causation hypothesis,” traditionally used in studies of social-epidemiology, has experienced a serious shift within social-epidemiological research over the last decade. Instead of merely focusing on how social factors affect one’s probability for illness, various scholars have highlighted that health (and illness) are not only results of specific social determinants but can also build and shape our class status. In this sense, fat people are generally accused of being lazy, undisciplined, unmotivated and emotionally unstable, and thus experience labor-market discriminations (e.g. lower income, decreased chances for higher education, higher job insecurity) that lead to a specific social class positioning. This can be then termed “reverse causality.”
Rethinking Class and Fatness in Current Social-Epidemiology
In the aforementioned review that compared these two contesting scenarios (“causation hypothesis” vs. “reverse causality”), my colleague Olaf von dem Knesebeck and I found an overall of 21 studies that empirically examined the link between income and “obesity” in a longitudinal design (at least two surveys with the same respondents over time). While 14 studies focused on how income affects the subsequent risk for obesity,” seven studies assessed in which way fatness influences individual chances for income and wages on the labor market.
Summarizing the results of the studies under review, our research indicated that both perspectives help to explain the association between income inequalities and fatness. However, there was a publication bias in studies testing the “causation hypothesis.” With the help of a specific statistical test (“Egger`s regression test for publication bias”) we investigated whether the effect estimates from studies were skewed, especially in studies with smaller sample sizes. Apparently, studies were likely to be rejected and thus remained unpublished if no significant statistical relation between income and “obesity” was reported. This implies inconsistent evidence for the argument that people with lower income have a higher risk of becoming fat.
And since this publication bias could not be found for studies that relied on the “reverse causality” perspective, overall findings imply that there is stronger and more consistent evidence that fatness leads to less social opportunities and lower status. In this light, it is more likely that the presumed association between income and fatness does not stem from the health-related behavior of people from lower social classes, but rather originates from how fat people are treated and devalued in the educational system (e.g. lower chances for higher education due to stigmatization) and on the labor-market. In terms of findings from stigma research that examine negative stereotypes and the social rejection of fat bodies in Western societies, this may not be too surprising. Nonetheless, this evidence shows that our concepts of healthful behavior and our evaluations of body norms can be powerful tools in shaping social reality.
In conclusion, current findings from studies in social epidemiology and stigma research emphasize that there is not a linear link between class and fatness, in which poverty automatically leads to fatness due to less “healthy” lifestyles and foods. Instead, these studies now also focus on the social effects of body politics, in examining the stigmatization and discrimination of fat bodies.
These different insights do not only provide a more complex view of the relation between class and fatness, but also offer new instruments to rethink prevailing stereotypes and prejudices as powerful elements in public health research. And maybe we are about to experience the beginning of more interdisciplinary work within social epidemiology, when the question if fatness is a class issue meets the exploration why fatness has become a (class) issue in the first place.