Validation of dietary intakes measured by diet history against 24 h urinary nitrogen excretion and energy expenditure measured by the doubly-labelled water method in middle-aged women.

TitleValidation of dietary intakes measured by diet history against 24 h urinary nitrogen excretion and energy expenditure measured by the doubly-labelled water method in middle-aged women.
Publication TypeJournal Article
Year of Publication2000
AuthorsBlack, AE, Welch, AA, Bingham, SA
JournalBr J Nutr
Volume83
Issue4
Pagination341-54
Date Published2000 Apr
ISSN0007-1145
KeywordsAged, Basal Metabolism, Calorimetry, Diet Records, Energy Intake, Energy Metabolism, Female, Humans, Hydrogen, Middle Aged, Nitrogen, Oxygen Isotopes, Reproducibility of Results, Seasons, Water
Abstract

A diet history method for estimating energy and N intakes was validated against 24 h urinary N excretion and energy expenditure measured by the doubly-labelled water (DLW) method. Forty-eight women aged 50-65 years were studied over 1 year. Weighed diet records from 4 d and two 24 h urine collections, for measurement of urinary N excretion, were obtained in each of four seasons. At the end of the year, a diet history was obtained, BMR was measured by whole-body calorimetry, and, in sixteen women, total energy expenditure (EE) was measured by DLW. Energy intake (EI) and N intake (NI) were calculated using food tables. Using weighed records and diet history respectively mean NI were 11.21 (SD 2.09) g and 11.47 (SD 2.40) g (NS) and EI were 8.08 (SD 1.54) MJ and 8.20 (SD 1.86) MJ (NS). Mean urine N:NI and EI:BMR values indicated bias to under-reporting by weighed record and diet history techniques in some individuals, but there was no significant difference between these measures at the group level. The Pearson correlation coefficient (r) for urine N v. NI was 0.81 for the weighed record and 0.38 for the diet history. The correlation of EE v. EI was r 0.48 for weighed record and r 0.11 for diet history. In this study the diet history gave the same estimate of mean intake, but the weighed record appeared to perform better in ranking individuals.

DOI10.1017/s0007114500000441
Alternate JournalBr. J. Nutr.
Citation Key10.1017/s0007114500000441
PubMed ID10858692