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European Journal of Clinical Nutrition (2013) 67, S79S85& 2013 Macmillan Publishers Limited All rights reserved 0954-3007/13
http://www.nature.com/ejcn
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ORIGINAL ARTICLE
The use of bioelectrical impedance analysis for body composition in epidemiological studies
A Bhm and BL Heitmann
BACKGROUND/OBJECTIVES: Bioelectrical impedance analysis (BIA) is a relatively simple, inexpensive and non-invasive technique to measure body composition and is therefore suitable in eld studies and larger surveys.
SUBJECTS/METHODS: We performed an overview of BIA-derived body fat percentages (BF%) from 55 published studies of healthy populations aged 680 years. In addition, the relationship between body mass index (BMI) and body composition is documented in the context of BIA as a good alternative to closely differentiate which composition of the body better relates to the risk of cardiovascular diseases (CVDs)and all-cause mortality.
RESULTS AND CONCLUSIONS: BIA-estimated percentage of BF varies greatly with population and age. BIA-estimated BF% is directly and closely related to various health outcomes such as CVDs, which is in contrast to BMI where both high and low BMIs are associated with increased risk of developing chronic diseases. Studies, among others using BIA, suggest that low BMI may reect low muscle and high BMI fat mass (FM). BIA-derived lean and FM is directly associated with morbidity and mortality. To the contrary, BMI is rather of limited use for measuring BF% in epidemiological studies.
European Journal of Clinical Nutrition (2013) 67, S79S85; doi:http://dx.doi.org/10.1038/ejcn.2012.168
Web End =10.1038/ejcn.2012.168
Keywords: bioelectrical impedance; percentage body fat; body mass index; mortality
INTRODUCTIONObesity is a condition in which fat accumulates in the body1 and the body fat percentage (BF%) is therefore the relevant measure of obesity. In the 1980s, bioelectrical impedance analysis (BIA) was introduced as a new method to be used for estimating body composition,2 and since then many studies have investigated its validityindeed, because then BIA has been widely applied for predicting body composition (for example, fat-free mass (FFM), total body water and BF) in healthy subjects with normal uid distribution,35 and the method is considered useful in relation to estimating BF% in both epidemiological and clinical research.6 Moreover, Wells and Fewtrell7 described BIA as the only predictive technique that estimates lean mass.
It is widely recognised that calculation of body composition measures from BIA requires population-specic equations, as also illustrated...