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Natural abundance deuterium and 18-oxygen effects on the precision of the doubly labeled water method
Author and Affiliation:
Horvitz, M. A.(University of Wisconsin-Madison, Department of Nutritional Sciences, Madison, Wisconsin 53706, United States)
Schoeller, D. A.
Abstract: The doubly labeled water method for measuring total energy expenditure is subject to error from natural variations in the background 2H and 18O in body water. There is disagreement as to whether the variations in background abundances of the two stable isotopes covary and what relative doses of 2H and 18O minimize the impact of variation on the precision of the method. We have performed two studies to investigate the amount and covariance of the background variations. These were a study of urine collected weekly from eight subjects who remained in the Madison, WI locale for 6 wk and frequent urine samples from 14 subjects during round-trip travel to a locale > or = 500 miles from Madison, WI. Background variation in excess of analytical error was detected in six of the eight nontravelers, and covariance was demonstrated in four subjects. Background variation was detected in all 14 travelers, and covariance was demonstrated in 11 subjects. The median slopes of the regression lines of delta2H vs. delta18O were 6 and 7, respectively. Modeling indicated that 2H and 18O doses yielding a 6:1 ratio of final enrichments should minimize this error introduced to the doubly labeled water method.
Publication Date: Jun 01, 2001
Document ID:
20040112447
(Acquired Oct 05, 2004)
Subject Category: LIFE SCIENCES (GENERAL)
Document Type: Journal Article
Publication Information: American journal of physiology. Endocrinology and metabolism (ISSN 0193-1849); Volume 280; 6; E965-72
Publisher Information: United States
Description: In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
NASA Terms: DEUTERIUM; ERGOMETERS; METABOLISM; OXYGEN; OXYGEN ISOTOPES; PRECISION; WATER; ADULTS; CLIMATE; FEMALES; ISOTOPIC LABELING; MALES; TRAVEL; WISCONSIN; YOUTH
Other Descriptors: DEUTERIUM/DIAGNOSTIC USE/URINE; ENERGY METABOLISM/PHYSIOLOGY; ERGOMETRY/STANDARDS; OXYGEN ISOTOPES/DIAGNOSTIC USE/URINE; WATER SUPPLY/STANDARDS; ADOLESCENT; ADULT; CLIMATE; FEMALE; HUMAN; ISOTOPE LABELING/STANDARDS; MALE; MIDDLE AGED; REPRODUCIBILITY OF RESULTS; TRAVEL; WATER/CHEMISTRY; WISCONSIN; NASA DISCIPLINE REGULATORY PHYSIOLOGY; NON-NASA CENTER
Availability Source: Other Sources
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