Measurement of longitudinal changes in body composition during weight loss and maintenance in overweight and obese subjects using air-displacement plethysmography in comparison with the deuterium dilution technique

Abstract

Background: Air-displacement plethysmography (ADP) may be a valid and practical technique to assess body composition in a clinical setting. Objective. This study aimed to assess longitudinal changes in body composition using ADP and to compare it with the deuterium dilution technique. Design: The study was a 6-months dietary intervention, consisting of four phases. The first month, subjects were fed in energy balance (phase I). This was followed by 1 month with an energy intake of 33% of energy requirements (phase II), followed by 2 months at 67% of energy requirements (phase III) and 2 months of ad libitum intake (phase IV). Body composition was assessed using ADP (Bod Pod) and deuterium dilution at baseline and at the end of each phase. The baseline analysis included 111 subjects (88 female). Sixty-one subjects (50 female) completed all measurements and were included in the longitudinal analysis. Results: At baseline, the fat mass (FM) as assessed with the Bod Pod was on average 2.3 ± 4.2 kg (mean ± 2 s.d.) higher than that assessed with deuterium dilution. The difference in FM between techniques increased significantly with increasing FM (R 2 ¼ 0.23; Po0.001). Both techniques showed significant changes in FM over time Po0.001). On average, FM as assessed with the Bod Pod was 2.0 kg higher than with deuterium dilution (Po0.001). During phase II, there was a significant interaction between time and method, meaning that the Bod Pod showed a larger decrease in FM than deuterium dilution. Conclusions: The Bod Pod was able to detect all changes in the body composition, but consistently measured a higher FM than deuterium dilution.

Long-Term Green Tea Extract Supplementation Does Not Affect Fat Absorption, Resting Energy Expenditure, and Body Composition in Adults

“…Sixty-five healthy, normal-weight [BMI (kg/m 2 ): [18][19][20][21][22][23][24][25] or overweight/obese (BMI $25) Caucasian subjects were included in the study. Subjects were 11 men and 54 women, aged between 18-50 y.…”

“…BMI was calculated as body weight (kg) divided by height (m) squared. Fat mass was determined by Bod Pod (Life Measurement, Inc) measurements (air displacement plethysmography) (25). Fat mass index was calculated by fat mass (kg) divided by height (m) squared.…”

Normal Protein Intake Is Required for Body Weight Loss and Weight Maintenance, and Elevated Protein Intake for Additional Preservation of Resting Energy Expenditure and Fat Free Mass

“…Body composition was calculated from body volume, measured by means of the BodPod (20), and total body water measured by means of the 2 H 2 O dilution technique using SiriÕs (21-23) 3-compartment model. The dilution of the 2 H 2 O isotope is a measure for total body water.…”

Acute Effects of Capsaicin on Energy Expenditure and Fat Oxidation in Negative Energy Balance

“…Fat mass (FM) was calculated as body weight minus TBW divided by the hydration factor 0.73. Additionally, FM was determined by Bodpod [21] measurements. Fat mass index (FMI) was calculated by FM (kg) divided by height (m) squared.…”