Complex systems approaches to identify policy levers to reduce racial/ethnic disparities in diet and obesity in cities

项目摘要 饮食和肥胖方面的种族/民族差异在美国各城市之间非常一致。首先，我们将使用 建立小组模式，系统地让学术、政策和社区利益相关者参与能力建设 对于系统思维，开发和完善驱动饮食差异的多层次因素的“地图”，并确定 减少城市饮食差异的政策杠杆。这项工作的需要是由于缺乏现有的 一个概念框架，通过它阐明了肥胖环境和系统的机制， 结构性不利条件对少数群体造成不成比例的影响，并导致不平等。以往研究和 现有的概念框架已经确定了对普通人群饮食的无数影响， 更具体的概念框架可以促进对社会、环境和政策因素的理解 这些因素结合在一起，限制了黑人、拉丁美洲人和其他少数民族的健康食品选择。 其次，我们将实施一个基于代理的模拟模型（ABM），以研究如何居住隔离， 食品出口的不公平分配、不健康食品的低价和收入不平等， 这两种组合限制了少数种族/族裔的食物选择，并导致饮食和肥胖方面的差异。的 ABM连接了我们小组和其他使用ABM来研究食物 获取和粮食价格分别影响饮食。通过集成这些独立的建模范例，我们可以 研究由于在获得食物和负担能力方面的交叉劣势，饮食差异是如何出现的。在 ABM，虚拟城市中的个体代理人做出一系列日常决策，比如去哪里买食物， 买什么食物，吃什么。每个决定都基于简单的规则，这些规则反映了对 食品采购和饮食，包括家庭食品预算;前往食品店的差旅费;店间 价格、库存和质量的变化;以及12种营养重要食品类别的价格（例如， 蛋白质、全谷物）和6种饮料类别。我们使用有关家庭收入的黄金标准数据， 食品支出、食品价格和购买以及饮食。我们建议反弹道导弹有两个用途：第一，我们将评估 与COVID-19大流行和限制资格的联邦政策有关的工作和收入损失的影响 以及移民在食品援助计划中的登记--两者对移民的影响都不成比例。 少数群体，从而可能加剧不平等。第二，我们将与政策利益攸关方合作， 传播和评估如何扩大现有的试点方案（例如，健康食品配送， 在农贸市场上花费的SNAP美元的价值，增加了少数民族社区的健康食品获得） 以及实施当前的政策建议（例如，美国农业部提议用“收获箱”取代SNAP）， 加剧或减少饮食差异。反弹道导弹是在费城的背景下，但研究 问题和发现与基本上所有美国城市的饮食差异高度相关。

PROJECT SUMMARY Racial/ethnic disparities in diet and obesity are remarkably consistent across U.S. cities. First, we will use group model building to systematically engage academic, policy, and community stakeholders to build capacity for systems thinking, develop and refine a “map” of the multilevel factors that drive diet disparities, and identify policy levers to reduce diet disparities in cities. The need for this work is motivated by the lack of an existing conceptual framework that explicates mechanisms via which obesogenic environments and systematic structural disadvantage disproportionately affect minorities and lead to disparities. Previous research and existing conceptual frameworks have identified myriad influences on diet among the general population, but a more specific conceptual framework can advance understanding of social, environmental, and policy factors that work in combination to constrain healthy food choices of Blacks, Latinos, and other racial/ethnic minorities. Second, we will implement an agent-based simulation model (ABM) to examine how residential segregation, the inequitable distribution of food outlets, the lower price of unhealthy foods, and income inequality work in combination to constrain food choices of racial/ethnic minorities and lead to diet and obesity disparities. The ABM bridges lines of research conducted by our group and others that have used ABM to examine how food access and food prices separately affect diets. By integrating these separate modeling paradigms, we can examine how diet disparities emerge due to intersecting disadvantage in food access and affordability. In the ABM, individual-agents in a virtual city make a series of daily decisions about where to shop for food, what types of food to purchase, and what to eat. Each decision is based on simple rules that reflect influences on food purchasing and diet, including household food budgets; travel costs to food stores; between-store variation in price, inventory, and quality; and the prices of 12 nutritionally important food categories (e.g., protein, whole grains) and 6 beverage categories. We use gold standard data regarding household income and food spending, food prices and purchasing, and diet. We propose two uses for the ABM: First, we will assess the impact of job and income loss related to the COVID-19 pandemic and federal policies that restrict eligibility and enrollment of immigrants in food assistance programs – both of which have a disproportionate effect on minorities and thus are likely to exacerbate disparities. Second, we will engage policy stakeholders to inform dissemination and evaluate how scaling up existing pilot programs (e.g., healthy food delivery, multiplying the value of SNAP dollars spent at farmers’ markets, increasing healthy food access in minority neighborhoods) and implementing current policy proposals (e.g., USDA proposal to replace SNAP with “harvest boxes”) will exacerbate or reduce diet disparities. The ABM is grounded in the Philadelphia context, but the research questions and findings are highly relevant to diet disparities in essentially all U.S. cities.