Lissner L, Troiano R P, Midthune D, Heitmann B L, Kipnis V, Subar A F, Potischman N
Department of Public Health and Community Medicine, Sahlgrenska Academy at Göteborg University, Sweden, and Research Unit for Dietary Studies at Institute of Preventive Medicine, Copenhagen University Hospital, Denmark.
Int J Obes (Lond). 2007 Jun;31(6):956-61. doi: 10.1038/sj.ijo.0803527. Epub 2007 Feb 13.
Obesity-related under-reporting of usual dietary intake is one of the most persistent sources of bias in nutrition research. The aim of this paper is to characterize obese and non-obese individuals with respect to reporting errors observed with two common dietary instruments, using energy and protein recovery biomarkers as reference measures.
This report employs data from the Observing Protein and Energy Nutrition (OPEN) study. Analyses are based on stratified samples of 211 (57 obese) men and 179 (50 obese) women who completed 24-h recalls (24HR), food frequency questionnaires (FFQ), doubly labelled water (DLW) and urinary nitrogen (UN) assessments.
In obese and non-obese subgroups, FFQ yielded lower energy and protein intake estimates than 24HR, although biomarker-based information indicated under-reporting with both dietary instruments. Gender differences in obesity-related bias were noted. Among women, the DLW-based energy requirement was 378 kcal greater in obese than in non-obese groups; the FFQ was able to detect a statistically significant portion of this extra energy, while the 24HR was not. Among men, the DLW-based energy requirement was 485 kcal greater in the obese group; however, neither FFQ nor 24HR detected this difference in energy requirement. Combining protein and energy estimates, obese men significantly over-reported the proportion of energy from protein using the 24HR, but not with the FFQ. In obese women, no significant reporting error for energy percent protein was observed by either method. At the individual level, correlations between energy expenditure and reported energy intake tended to be weaker in obese than non-obese groups, particularly with the 24HR. Correlations between true and reported protein density were consistently higher than for protein or energy alone, and did not vary significantly with obesity.
This work adds to existing evidence that neither of these commonly used dietary reporting methods adequately measures energy or protein intake in obese groups. The 24HR, while capturing more realistic energy distributions for usual intake, may be particularly problematic in the obese.
肥胖相关的日常饮食摄入量报告不足是营养研究中最持久的偏差来源之一。本文旨在利用能量和蛋白质恢复生物标志物作为参考指标，通过两种常见饮食工具观察到的报告误差来描述肥胖和非肥胖个体的特征。
本报告采用了观察蛋白质和能量营养（OPEN）研究的数据。分析基于211名（57名肥胖）男性和179名（50名肥胖）女性的分层样本，这些参与者完成了24小时回顾法（24HR）、食物频率问卷（FFQ）、双标水法（DLW）和尿氮（UN）评估。
在肥胖和非肥胖亚组中，FFQ得出的能量和蛋白质摄入量估计值低于24HR，尽管基于生物标志物的信息表明两种饮食工具均存在报告不足的情况。注意到了肥胖相关偏差的性别差异。在女性中，基于DLW的肥胖组能量需求比非肥胖组高378千卡；FFQ能够检测到这部分额外能量的统计学显著部分，而24HR则不能。在男性中，基于DLW的肥胖组能量需求高485千卡；然而，FFQ和24HR均未检测到这种能量需求差异。综合蛋白质和能量估计值，肥胖男性使用24HR时显著高估了蛋白质能量比例，但使用FFQ时未出现这种情况。在肥胖女性中，两种方法均未观察到能量蛋白质百分比的显著报告误差。在个体层面，肥胖组的能量消耗与报告的能量摄入量之间的相关性往往比非肥胖组弱，尤其是使用24HR时。真实蛋白质密度与报告蛋白质密度之间的相关性始终高于单独的蛋白质或能量，且不因肥胖而有显著差异。
这项研究补充了现有证据，即这两种常用的饮食报告方法均不能充分测量肥胖组的能量或蛋白质摄入量。24HR虽然能捕捉到更符合实际的日常摄入量能量分布，但在肥胖人群中可能尤其存在问题。
