How well do waist circumference and body mass index reflect body composition in pre-pubertal children?

• Published in: European journal of clinical nutrition Vol. 63; no. 9; pp. 1065 - 1070
• Main Authors: Cameron, N, Jones, L.L, Griffiths, P.L, Norris, S.A, Pettifor, J.M
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.09.2009; Nature Publishing Group
• Subjects: Absorptiometry, Photon; Adipose Tissue; Adiposity; Anthropometry; Biological and medical sciences; Black People; Body Composition; Body fat; Body Height; Body Mass Index; Body size; Child; Children; Children & youth; Clinical Nutrition; Cohort Studies; Correlation coefficient; Correlation coefficients; Cross-Sectional Studies; Demographic aspects; Diagnosis; Dual energy X-ray absorptiometry; Epidemiology; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Health aspects; Humans; Internal Medicine; Male; Medical sciences; Medicine; Medicine & Public Health; Metabolic Diseases; Obesity; original-article; Overweight - diagnosis; Overweight - diagnostic imaging; Overweight - ethnology; Physical growth; Physiological aspects; Preteens; Puberty; Public Health; Risk factors; Size; South Africa; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Waist Circumference; South Africa; United Kingdom; pre-pubertal children; lean mass; waist circumference; fat mass; BMI; Human; Puberty; Anthropometry; Metabolic diseases; Corporal biometry; Fat mass; Body composition; Body mass index; Waist circumference; Waist hip ratio; Child
• ISSN: 0954-3007; 1476-5640; 1476-5640
• DOI: 10.1038/ejcn.2009.26

Objective: To investigate the quantitative relationship between waist circumference (WC) and height (Ht), and subsequently the association between waist circumference index (WCI), body mass index (BMI) and body composition in pre-pubertal children. Design: Cross-sectional sample (n=227; boys=127) of pre-pubertal black children (age range 8.8-11.0 years) from the Bone Health sub-study of the Bt20 birth cohort study set in Soweto-Johannesburg, South Africa. Measures of height, weight and WC by anthropometry, total and truncal fat and lean mass by dual-energy X-ray absorptiometry were used in the analysis. Pearson's correlation coefficients were used to examine the associations between BMI, WC and body composition outcomes. Results: WC was independent of height when height was raised to a power of 0.8. BMI and WCI (WC/Ht) were significantly associated with total and truncal fat and lean mass in both sexes (all P<0.001). BMI showed consistently and significantly higher correlations with body composition than WCI and this association was significantly greater for fat mass than lean mass. Conclusion: BMI, rather than WCI, would be a better screening tool for total and truncal fat mass in both sexes before puberty.