Assessment of Energy Intake in Free-Living Subjects Using Stable Isotopes

使用稳定同位素评估自由生活受试者的能量摄入

• 批准号: 7502117
• 负责人: JOSEPH J KEHAYIAS
• 金额: $ 13.21万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-30 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7502117
• 关键词: Adipose tissue; Adult; Body Composition; Breath Tests; Carbohydrates; Carbon; Carbon Dioxide; Clinical; Computer Simulation; Data; Detection; Dose; Eating; Energy Intake; Energy Metabolism; Equation; Fatty Acids; Fatty acid glycerol esters; Individual; Intake; Isotopes; Kinetics; Label; Life; Measurement; Measures; Methods; Modeling; Monitor; Obesity; Outcomes Research; Overweight; Patient Self-Report; Pattern; Proteins; Purpose; Questionnaires; Research; Shapes; Simulate; Standards of Weights and Measures; Testing; Today; Validation; Water; Work; base; day; energy balance; indexing; mathematical model; models and simulation; research study; stable isotope; time use; tool

DESCRIPTION (provided by applicant): Obesity is a problem of energy balance. When energy expenditure does not keep up with intake, then adipose tissue accumulates to excess levels. Modern tools are available for monitoring two of the three components of the energy equation: body composition and energy expenditure. Energy intake, however, is still evaluated by standard self-report questionnaires on food intake. The questionnaire-based tools are useful in providing data on dietary patterns, but can be inaccurate and biased especially for overweight individuals who may underreport their energy intake. The purpose of the proposed exploratory research is to develop a practical tool that can measure average energy intake in free-living adults. In this proposal we present evidence that simple monitoring of isotope clearance in breath CO2 can provide quantitative information on fat, protein and carbohydrate intake. Our approach includes both mathematical modeling and clinical validation. The mathematical model will simulate the kinetics of C-13 labeled fatty acid as a function of fat, protein and carbohydrate intake, body composition, and energy expenditure. A dose of C-13 labeled fatty acid is followed by C-13 detection in breath for several days. Work with a preliminary computer simulation model indicates that fat and protein intake have different and predictable effects on the shape of the C-13 elimination curve. The detailed kinetic parameters of the isotope clearance will be measured experimentally. A second experiment will test the hypothesis that the C-13/C-12 ratio in breath after dosing with C-13 labeled fatty acid is an index of total fuel intake, by using a total body carbon pool model and dosing with every meal. The outcome of this research will be a fully developed stable-isotope based tool to serve energy balance studies by evaluating energy intake. If successful, it will become for energy intake what doubly labeled water is today for energy expenditure.

描述（由申请人提供）： 肥胖是能量平衡的问题。当能量消耗不跟上摄入量时，脂肪组织会累积到过高的水平。现代工具可用于监视能量方程的三个组成部分中的两个：车身成分和能量消耗。但是，仍然可以通过标准的自我报告问卷调查食品摄入量来评估能量摄入量。基于问卷的工具对于提供有关饮食模式的数据很有用，但对于可能低估其能量摄入的超重个人可能是不准确和偏见的。拟议的探索性研究的目的是开发一种可以衡量自由生活成年人平均能量摄入的实用工具。在此提案中，我们提供了证据表明，对呼吸二氧化碳中同位素清除率的简单监测可以提供有关脂肪，蛋白质和碳水化合物摄入的定量信息。我们的方法包括数学建模和临床验证。数学模型将模拟C-13标记的脂肪酸的动力学，这是脂肪，蛋白质和碳水化合物摄入，身体成分和能量消耗的函数。一剂C-13标记的脂肪酸，然后在呼吸中检测几天。使用初步计算机模拟模型的工作表明，脂肪和蛋白质摄入对C-13消除曲线的形状具有不同的可预测影响。同位素间隙的详细动力学参数将进行实验测量。第二个实验将检验以下假设：用C-13标记的脂肪酸给药后的C-13/C-12比率是总燃料摄入量的指数，它是使用总体碳池模型和每餐用来给药的。这项研究的结果将是一种完全开发的基于稳定的异位素工具，可通过评估能量摄入来服务能量平衡研究。如果成功的话，它将成为能源摄入，如今标记的水是用于能源消耗的。