Misreporting of Energy Intake in the Elderly Using Doubly Labeled Water to Measure Total Energy Expenditure and Weight Change

This study was supported by National Institute on Aging contracts N01-AG-6-2101, N01-AG-6-2103, and N01-AG-6-2106, with additional support from the National Institute of Diabetes and Digestive and Kidney Diseases. This research was supported in part by the Intramural Research Program of the NIH, National Institute on Aging.

None of the authors have any financial or any other kind of personal conflicts with this article.

Abstract

Background: One of the major problems in dietary assessment is inaccuracy in reporting diet.

Objective: To examine the association between self-reported energy intake (EI) by food frequency questionnaire (FFQ) and energy expenditure (EE), measured by doubly labeled water (DLW), among older persons.

Design: EE was assessed in 298 high-functioning, community-dwelling older adults (70–79 years of age) over a 2-week period using DLW. Dietary intake was assessed using a Block FFQ. The ratio between reported EI and total energy expenditure (TEE) was calculated. Misreporting was defined as follows: participants with an EI/TEE ratio of <0.77 were categorized as low energy reporters, while participants with an EI/TEE ratio >1.28 were categorized as high energy reporters. Participants with an EI/TEE ratio of 0.77–1.28 were categorized as “true” energy reporters. One-year percent weight change prior to EE visit was used as another validation indicator. Participants who were low energy reporters but lost >2% of their body weight were categorized as undereaters.

Results: Two hundred ninety-six participants provided both FFQ and DLW measurements. Forty-three percent of participants were low energy reporters; among them, almost 30% lost weight and, therefore, were categorized as undereaters. The undereaters consumed significantly fewer calories. No difference in the frequency of low energy reporting was detected between genders or racial groups. Underreporters had significantly higher body weight than “true” or high reporters. Undereaters tended to have higher body mass index than the underreporters.

Conclusions: Undereating is prevalent in the elderly and may be falsely perceived as underreporting. It should be further addressed and characterized in future studies.

• doubly labeled water
• misreporting
• dietary intake
• true energy reporters
• undereating

Author Contributions. D.R. Shahar conceptualized the idea, analyzed the data, and wrote the first draft of the manuscript. T.B. Harris (project officer at National Institute on Aging) contributed to the conceptualization of the idea, interpreted the data, and contributed to drafts of the manuscript. D.K. Huston and J.S. Lee interpreted the statistical analyses and reviewed drafts of the paper. F.A. Tylavsky and S.B. Kritchevsky are co-investigators of the study, contributed to the data collection, interpreted the results, and reviewed drafts of the paper. D.E. Sellmeyer contributed to data management and data analyses, interpreted the data, and contributed to drafts of the manuscript. B. Yu was responsible for the statistical analyses and interpretation and reviewed drafts of the manuscript. All authors approved the last version of the manuscript.