Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO.
School of Public Health, University of West Virginia, Morgantown, WV.
J Nutr. 2018 Mar 1;148(3):490-496. doi: 10.1093/jn/nxx029.
Assessments of energy intake (EI) are frequently affected by measurement error. Recently, a simple equation was developed and validated to estimate EI on the basis of the energy balance equation [EI = changed body energy stores + energy expenditure (EE)].
The purpose of this study was to compare multiple estimates of EI, including 2 calculated from the energy balance equation by using doubly labeled water (DLW) or activity monitors, in free-living adults.
The body composition of participants (n = 195; mean age: 27.9 y; 46% women) was measured at the beginning and end of a 2-wk assessment period with the use of dual-energy X-ray absorptiometry. Resting metabolic rate (RMR) was calculated through indirect calorimetry. EE was assessed with the use of the DLW technique and an arm-based activity monitor [Sensewear Mini Armband (SWA); BodyMedia, Inc.]. Self-reported EI was calculated by using dietitian-administered 24-h dietary recalls. Two estimates of EI were calculated with the use of a validated equation: quantity of energy stores estimated from the changes in fat mass and fat-free mass occurring over the assessment period plus EE from either DLW or the SWA. To compare estimates of EI, reporting bias (estimated EI/EE from DLW × 100) and Goldberg ratios (estimated EI/RMR) were calculated.
Mean ± SD EEs from DLW and SWA were 2731 ± 494 and 2729 ± 559 kcal/d, respectively. Self-reported EI was 2113 ± 638 kcal/d, EI derived from DLW was 2723 ± 469 kcal/d, and EI derived from the SWA was 2720 ± 730 kcal/d. Reporting biases for self-reported EI, DLW-derived EI, and SWA-derived EI are as follows: -21.5% ± 22.2%, -0.7% ± 18.5%, and 0.2% ± 20.8%, respectively. Goldberg cutoffs for self-reported EI, DLW EI, and SWA EI are as follows: 1.39 ± 0.39, 1.77 ± 0.38, and 1.77 ± 0.38 kcal/d, respectively.
These results indicate that estimates of EI based on the energy balance equation can provide reasonable estimates of group mean EI in young adults. The findings suggest that, when EE derived from DLW is not feasible, an activity monitor that provides a valid estimate of EE can be substituted for EE from DLW.
能量摄入(EI)的评估经常受到测量误差的影响。最近,开发并验证了一个简单的方程,用于根据能量平衡方程估算 EI [EI=变化的体能量储存+能量支出(EE)]。
本研究的目的是比较多种 EI 估算值,包括通过使用双标记水(DLW)或活动监测器从能量平衡方程计算的 2 种估算值,用于自由生活的成年人。
参与者的身体成分(n=195;平均年龄:27.9 岁;46%为女性)在为期 2 周的评估期开始和结束时使用双能 X 射线吸收法进行测量。静息代谢率(RMR)通过间接测热法计算。EE 使用 DLW 技术和基于手臂的活动监测器[Sensewear Mini Armband(SWA);BodyMedia,Inc.]进行评估。自我报告的 EI 通过营养师进行的 24 小时膳食回忆计算。使用经过验证的方程计算了 2 种 EI 估算值:从评估期内脂肪质量和去脂体重变化估计的能量储存量加上来自 DLW 或 SWA 的 EE。为了比较 EI 的估算值,计算了报告偏差(来自 DLW 的估计 EI/EE×100)和戈德堡比值(估计 EI/RMR)。
来自 DLW 和 SWA 的平均±SD EE 分别为 2731±494 和 2729±559 kcal/d。自我报告的 EI 为 2113±638 kcal/d,来自 DLW 的 EI 为 2723±469 kcal/d,来自 SWA 的 EI 为 2720±730 kcal/d。自我报告 EI、DLW 衍生 EI 和 SWA 衍生 EI 的报告偏差分别为:-21.5%±22.2%、-0.7%±18.5%和 0.2%±20.8%。自我报告 EI、DLW EI 和 SWA EI 的戈德堡截止值分别为:1.39±0.39、1.77±0.38 和 1.77±0.38 kcal/d。
这些结果表明,基于能量平衡方程的 EI 估算值可以为年轻人的群体平均 EI 提供合理的估算值。研究结果表明,当无法从 DLW 获得 EE 时,可以使用提供 EE 有效估计值的活动监测器替代来自 DLW 的 EE。