Research has found a strong relationship between poverty and health, and lower levels of income are associated with higher levels of sickness and premature death. In seeking to understand this relationship, researchers often focus on what is called “allostatic load” — the wear and tear on the body as it manages physical and social stresses.

A 2012 study from Cornell University and University of Wisconsin-Madison published in Psychological Science, “Poverty and Health: The Mediating Role of Perceived Discrimination,” analyzed a sample of 252 adolescents who were part of a larger longitudinal study on rural poverty. The subject pool was 92% white, and discrimination levels were determined by asking for responses to statements such as “People treat me differently because of my background”; “I feel I am excluded from certain activities because of my background”; and “People do not respect me because of who I am.” The study looked at the relationship between poverty, perceived discrimination, allostatic load and other measures, and attempted to establish a link among them.

The study’s findings include:

• Poverty was associated with increased allostatic load, and thus higher levels of poverty were associated with higher levels of physiological stress.
• Greater poverty was linked to higher levels of perceived discrimination. Furthermore, there was a strong relationship between perceived discrimination and physiological stress.
• The strength of the effect of poverty on allostatic load decreased by 13% when the variable of perceived discrimination was included; however, the poverty-allostatic relationship still remained significant.
• Analyses of the relationship between Body Mass Index and poverty were conducted to address the “possibility that obesity drove the effects of poverty on perceived discrimination.” Although there was a significant relationship found between poverty and BMI, the relationship between BMI and perceived discrimination was not significant.
• After controlling for the effects of BMI on perceived discrimination, the “effects of poverty on allostatic load remained.” This suggests that “the stigma associated with obesity did not drive the effects of poverty on perceived discrimination, as measured in this study.”

The authors conclude that the “findings of this study show that social-class discrimination may be one mechanism underlying social gradients in health.” But they caution that proof of causation was not established: “Although the analyses presented here show an important link between perceived discrimination and physical health, testing the specific mechanisms underlying this effect was not within the scope of this investigation.”

Related research: A 2011 study from Harvard University examined how stress can help explain disparities in health outcomes along racial lines. Additionally, a 2011 study in the American Journal of Epidemiology explored how troubled neighborhoods are associated with higher community levels of depression.

Keywords: poverty, youth, inequality