An Agent-Based Model of Income Inequalities in Diet in the Context of Residential Segregation

Abstract

Background Low dietary quality is a key contributor to obesity and related illnesses, and lower income is generally associated with worse dietary profiles. The unequal geographic distribution of healthy food resources could be a key contributor to income disparities in dietary profiles. Purpose To explore the role that economic segregation can have in creating income differences in healthy eating and to explore policy levers that may be appropriate for countering income disparities in diet. Methods A simple agent-based model was used to identify segregation patterns that generate income disparities in diet. The capacity for household food preferences and relative pricing of healthy foods to overcome or exacerbate the differential was explored. Results Absent other factors, income differentials in diet resulted from the segregation of high-income households and healthy food stores from low-income households and unhealthy food stores. When both income groups shared a preference for healthy foods, low-income diets improved but a disparity remained. Both favorable preferences and relatively cheap healthy foods were necessary to overcome the differential generated by segregation. Conclusions The model underscores the challenges of fostering favorable behavior change when people and resources are residentially segregated and behaviors are motivated or constrained by multiple factors. Simulation modeling can be a useful tool for proposing and testing policies or interventions that will ultimately be implemented in a complex system where the consequences of multidimensional interactions are difficult to predict.

A Multilevel Model of Postmenopausal Breast Cancer Incidence

“…Another model developed by Galea and colleagues depicts how a complex system can shed light on how measures of social class and neighborhood can influence health and disease across time (153). Auchincloss and colleagues have developed agent-based models to examine neighborhood influences on diet and walking (154).…”

A systems approach to obesity

“…When using an ABM to compare access to supermarkets, physical activity infrastructure, and school quality, Orr et al 62 found that all 3 interventions decreased disparities in body mass index between black and white populations but noted nuances such as some interventions varying in their impact over time or having synergistic effects with other interventions. One such interaction between interventions was also present in an ABM developed by Auchincloss et al, 63 which showed that increasing both access to affordable healthy foods and preferences for such foods was necessary to reduce disparities in diet between households of different income levels. Systems modeling can identify circumstances that may cause a particular intervention to be more or less successful, as Li et al 64 found that the influence of a nutrition education campaign on individuals' food choices varied between neighborhoods depending on social norms.…”

Health in cities: is a systems approach needed?

“…The study of infectious diseases (because of the contagious nature of many infections) has long embraced and incorporated some features of systems in analytical approaches (such as the need to account for transmission from individual to individual and consequent dependencies), but only recently have systems approaches garnered attention in other areas of health 10,11,12 . Two important factors have contributed to this trend.…”

“…", whereas a more systems oriented question would be "What is the plausible impact on dietary health inequalities of a strategy to subsidize the location of supermarkets in certain areas under various spatial patterning scenarios?" 10 . These different kinds of questions allow for the possibility not only of directly assessing the plausible impact of various policies but also of identifying potentially useful policies that we might not have imagined (or identified as relevant) before performing the simulation modeling.…”