Body Fat Percentile Curves for
U.S. Children and Adolescents
Kelly R. Laurson, PhD, Joey C. Eisenmann, PhD, Gregory J. Welk, PhD
Background: To date, several studies have been published outlining reference percentiles for BMI
in children and adolescents. In contrast, there are limited reference data on percent body fat (%BF) in
Purpose: The purpose of this study was to derive smoothed percentile curves for %BF in a nationally
representative sample of U.S. children and adolescents.
Methods: Percent fat was derived from the skinfold thicknesses of those aged 5–18 years from three
cross-sectional waves of the National Health and Nutrition Examination Survey (NHANES) IV
(1999–2000, 2001–2002, and 2003–2004; N⫽8269). The LMS (L⫽skewness, M⫽median, and
S⫽coeffıcient of variation) regression method was used to create age- and gender-specifıc smoothed
percentile curves of %BF.
Results: Growth curves are similar between boys and girls until age 9 years. However, whereas %BF
peaks for boys at about age 11 years, it continues to increase for girls throughout adolescence. Median
%BF at age 18 years is 17.0% and 27.8% for boys and girls, respectively.
Conclusions: Growth charts and LMS values based on a nationally representative sample of U.S.
children and adolescents are provided so that future research can identify appropriate cut-off values
based on health-related outcomes. These percentiles are based on skinfolds, which are widely
available and commonly used. Using %BF instead of BMI may offer additional information in
epidemiologic research, fıtness assessment, and clinical settings.
(Am J Prev Med 2011;41(4S2):S87–S92) © 2011 American Journal of Preventive Medicine
he increasing prevalence
and adverse medical,
childhood obesity have been well documented.
The majority of studies that identify the magnitude and
consequences of this health problem rely on the classifı-
cation of overweight or obesity using age- and gender-
specifıc thresholds or reference values of BMI. Several
sets of reference values for BMI in children and adoles-
cents have been published, with the most widely recog-
nized being the international thresholds by Cole et al.
and the CDC thresholds.
Although these reference val-
ues are widely used, a major limitation of BMI is its
inherent inability to differentiate between fat mass and
Similar sets of reference values are needed
for body fatness to improve public health surveillance,
facilitate clinical screening, and advance obesity preven-
Despite the importance of body fatness to health, there
are limited reference data available on percent body fat
(%BF). Percentiles for body fat have been developed us-
ing bioelectrical impedance analysis (BIA)-derived %BF
values in British children
and skinfold-derived %BF
values in Spanish adolescents.
Both BIA and measuring
skinfold thickness are simple and feasible methods to
assess adiposity. In children and adolescents, skinfold
thickness values are often converted to %BF using the
as in the aforementioned study by
Moreno et al.
Rodriguez et al.
mended the use of the Slaughter equation for male and
female adolescents after reviewing several skinfold-to-
%BF prediction equations. Reference data are not cur-
rently available using skinfold-derived %BF in U.S.
youth. Therefore, this paper presents smoothed percen-
tile curves for %BF using LMS (L⫽skewness, M⫽
median, and S⫽coeffıcient of variation) regression in a
From the School of Kinesiology and Recreation, Illinois State University
(Laurson), Normal, Illinois; the Department of Kinesiology, Michigan State
University (Eisenmann), East Lansing, Michigan; The Healthy Weight
Center at Helen DeVos Children’s Hospital (Eisenmann), Grand Rapids,
Michigan; and the Department of Kinesiology, Iowa State University
(Welk), Ames, Iowa
Address correspondence to: Kelly R. Laurson, PhD, School of Kinesiol-
ogy and Recreation, Illinois State University, Campus Box 5120, 250
© 2011 American Journal of Preventive Medicine • Published by Elsevier Inc. Am J Prev Med 2011;41(4S2):S87–S92 S87