Predictive equation derived from 6,497 doubly labelled water measurements enables the detection of erroneous self-reported energy intake.

Nutritional epidemiology aims to link dietary exposures to chronic disease, but the instruments for evaluating dietary intake are inaccurate. One way to identify unreliable data and the sources of errors is to compare estimated intakes with the total energy expenditure (TEE). In this study, we used the International Atomic Energy Agency Doubly Labeled Water Database to derive a predictive equation for TEE using 6,497 measures of TEE in individuals aged 4 to 96 years.

Greater male variability in daily energy expenditure develops through puberty.

There is considerably greater variation in metabolic rates between men than between women, in terms of basal, activity and total (daily) energy expenditure (EE). One possible explanation is that EE is associated with male sexual characteristics (which are known to vary more than other traits) such as musculature and athletic capacity. Such traits might be predicted to be most prominent during periods of adolescence and young adulthood, when sexual behaviour develops and peaks.

Variation in human water turnover associated with environmental and lifestyle factors.

Water is essential for survival, but one in three individuals worldwide (2.2 billion people) lacks access to safe drinking water. Water intake requirements largely reflect water turnover (WT), the water used by the body each day.

Variability in energy expenditure is much greater in males than females.

In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits.

Total energy expenditure is repeatable in adults but not associated with short-term changes in body composition.

Low total energy expenditure (TEE, MJ/d) has been a hypothesized risk factor for weight gain, but repeatability of TEE, a critical variable in longitudinal studies of energy balance, is understudied. We examine repeated doubly labeled water (DLW) measurements of TEE in 348 adults and 47 children from the IAEA DLW Database (mean ± SD time interval: 1.9 ± 2.

Physical activity and fat-free mass during growth and in later life.

Background: Physical activity may be a way to increase and maintain fat-free mass (FFM) in later life, similar to the prevention of fractures by increasing peak bone mass.

Objectives: A study is presented of the association between FFM and physical activity in relation to age.

Methods: In a cross-sectional study, FFM was analyzed in relation to physical activity in a large participant group as compiled in the International Atomic Energy Agency Doubly Labeled Water database.

Energy compensation and adiposity in humans.

Understanding the impacts of activity on energy balance is crucial. Increasing levels of activity may bring diminishing returns in energy expenditure because of compensatory responses in non-activity energy expenditures. This suggestion has profound implications for both the evolution of metabolism and human health.

A standard calculation methodology for human doubly labeled water studies.

The doubly labeled water (DLW) method measures total energy expenditure (TEE) in free-living subjects. Several equations are used to convert isotopic data into TEE. Using the International Atomic Energy Agency (IAEA) DLW database (5,756 measurements of adults and children), we show considerable variability is introduced by different equations.

Hypertrophic remodelling in cardiac regulatory myosin light chain (MYL2) founder mutation carriers.

Aims: Phenotypic heterogeneity and incomplete penetrance are common in patients with hypertrophic cardiomyopathy (HCM). We aim to improve the understanding in genotype-phenotype correlations in HCM, particularly the contribution of an MYL2 founder mutation and risk factors to left ventricular hypertrophic remodelling.

Methods And Results: We analysed 14 HCM families of whom 38 family members share the MYL2 c.

Assessment of whole body protein metabolism in critically ill children: can we use the [15N]glycine single oral dose method?

Background & Aims: Most stable-isotope methods to evaluate whole body protein metabolism in patients are invasive and difficult to use in children. In this study protein metabolism was evaluated with the non-invasive [15N]glycine single oral dose method in critically ill children and the value of the method is discussed.

Methods: [15N]glycine (100mg) was given orally to children (mean age 5.

Physical activity level measured by doubly labeled water and accelerometry in children.

The present study investigated the use of a tri-axial accelerometer, Tracmor2, for the measurement of physical activity in children. Eleven children [age 6.9 (2.

Short-term effects of growth hormone on body composition as a predictor of growth.

The objective of this study was to investigate whether short-term changes in metabolism, as a result of GH therapy, could be used to predict its growth effect after 1 yr. Twenty-eight children (8.7 +/- 2.