Comparison of methods to assess body fat in non-obese six to seven-year-old children

Background & aim: Different non-invasive methods exist to evaluate total body fat in children. Most methods have shown to be able to confirm a high fat percentage in children with overweight and obesity. No data are available on the estimation of total body fat in non-obese children. The aim of this study is to compare total body fat, assessed by different methods in non-obese children. Methods: We compared total body fat, assessed by isotope dilution, dual energy X-ray, skinfold thickness, bioelectrical impedance analysis, combination of these methods as well as BMI in 30 six to seven-year-old children. Results: The children had a mean BMI of 16.01 kg/m(2) (range 13.51-20.32) and five children were overweight according to international criteria. Different methods showed rather different absolute values for total body fat. Bland-Altman analysis showed that the difference between the DEXA method and isotope dilution was dependent on the fat percentage. Children with the same BMI show a marked variation in total body fat ranging from 8% to 22% as estimated from the isotope dilution method. Conclusion: Non-invasive methods are presently not suited to assess the absolute amount of total body fat in 6-7 years old children. (c) 2009 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.