Accounting for the social gradient in diet quality and health

描述（由申请人提供）：美国农业部营养政策和促进中心（CNPP）于2008年5月发布了国家食品价格数据库，首次使美国人口不同阶层之间饮食质量和饮食成本之间关系的研究成为可能。这些价格是2001-2002年全国健康和营养调查（NHANES）代表性人口的食品消费价格。NHANES的数据包括24小时饮食回忆、体检和完成的详细人口统计和健康问卷。将食品价格矢量（$/100 g）与国家膳食研究食品和营养素数据库（FNDDS 1.0）联系起来，将能够在个人一级估计膳食的货币价值（$/天和$/2000千卡），同时估计膳食-疾病关联研究中常用的膳食暴露变量。能够将饮食成本与5，411名美国成年人（20岁）的NHANES饮食，人口统计学，社会经济学和生物标志物数据联系起来，将允许罕见地首次查看模型框架中的中间机制，将社会经济地位（SEP）与健康结果联系起来。能量和营养素摄入量将用于计算每个受访者饮食的能量密度和营养密度。能量调整饮食成本的新措施可能有助于解释肥胖，II型糖尿病和代谢综合征的社会梯度。分析将确定SEP的膳食能量密度，饮食质量和能量调整的饮食成本的预测，并将阐明它们之间的关系，这是从来没有做过的大规模代表性样本的美国成年人。主要假设是饮食质量和成本呈负相关;然而，这种关系的性质因性别、人种/种族和SEP分层而异。第二系列分析将提供有关关注亚组的饮食质量和成本的描述性数据，包括美国人口的高风险和脆弱亚组，包括食品援助接受者或患有慢性疾病的个人。在横断面研究的限制内，分析将探索饮食质量指标、饮食成本和健康结果之间的关系，包括测量的体重指数（BMI）、炎症生物标志物、代谢综合征的单个组分（例如，糖尿病、腹部肥胖、血脂异常、高血压、胰岛素抵抗、促血栓形成和炎症）、代谢综合征和糖尿病。其中许多与饮食的特定成分有关。该假设是，一旦将能量调整饮食成本纳入模型，饮食成分与健康之间的一些观察到的关联将被削弱。拟议中的研究提供了一个独特的第一次看在美国的健康和不健康的饮食成本和食品定价对健康的后果。 公共卫生相关性： 本研究的目的是评估不同社会经济和人口特征的群体所消费的饮食成本和质量之间的关系。这项研究是由国家食品价格的新数据，将与基于人口的饮食摄入量调查合并。这项工作解决了营养饮食的经济障碍，从而为健康方面的社会经济差异研究提供了重要组成部分。这项研究的长期目标是建立一种新的方法来估计饮食成本，直接联系到营养摄入量的估计。该方法将使研究人员能够评估食品成本作为影响个人和大群体饮食行为的一个因素。

DESCRIPTION (provided by applicant): The study of the relation between diet quality and diet cost among different strata of the US population has been made possible, for the first time, by the release of the national food price database by the USDA Center for Nutrition Policy and Promotion (CNPP) in May 2008. The prices were for foods consumed by the participants in the representative population-based 2001-2002 National Health and Nutrition Examination Survey (NHANES). The NHANES data include a 24-hour dietary recall, a medical examination and completed detailed demographic and health questionnaires. Linking the food price vector ($/100g) with the national Food and Nutrient Database for Dietary Studies (FNDDS 1.0) will allow for the estimation of the monetary value of the diet ($/day and $/2000kcal) at the individual-level, in parallel with the estimation of dietary exposure variables commonly used in studies of diet-disease associations. Being able to link diet costs with the NHANES dietary, demographic, socioeconomic and biomarker data for 5,411 US adults (agee20) will permit a rare first look at the intermediate mechanisms in the model framework that links socioeconomic position (SEP) and health outcomes. Energy and nutrient intakes will be used to calculate energy density and nutrient density of each respondent's diet. The new measure of energy-adjusted diet cost may help explain the observed social gradient in obesity, type II diabetes and the metabolic syndrome. Analyses will identify SEP predictors of dietary energy density, diet quality and energy-adjusted diet cost and will elucidate the relations among them, something that has never been done in a large-scale representative sample of US adults. The primary hypothesis is that diet quality and cost will be inversely linked; however the nature of that relation will differ by gender, race/ethnicity and SEP strata. The second series of analyses will provide descriptive data on diet quality and cost for subgroups of interest, including high-risk and vulnerable subgroups of the US population, including food assistance recipients or individuals with established chronic disease. Within the limitations of a cross-sectional study, analyses will explore the relation between diet quality measures, diet cost and health outcomes, including measured body mass index (BMI), biomarkers of inflammation, individual components of the metabolic syndrome (e.g., diabetes, abdominal obesity, dyslipidemia, high blood pressure, insulin resistance, prothrombosis and inflammation), the metabolic syndrome and diabetes. Many of those have been linked to specific components of the diet. The hypothesis is that some of the observed associations between dietary components and health will be attenuated once energy-adjusted diet costs are included in the model. The proposed studies offer a unique first look at the cost of healthful and unhealthful diets in the US and the consequences of food pricing on health. PUBLIC HEALTH RELEVANCE: The purpose of this research is to assess the relationship between the cost and quality of diets consumed by groups differing in socioeconomic and demographic characteristics. The study is made possible by new data on national food prices that will be merged with a population-based dietary intake survey. This work addresses economic barriers to nutritious diets and thus provides a vital part of the research on socio-economic disparities in health. The long term goal of this research is to establish a new approach to estimating diet cost that links directly to estimates of nutrient intake. The approach will allow investigators to assess food cost as a factor influencing the dietary behaviors of individuals and large populations.