Abstract:
Background: Data on body composition in infancy may improve
the understanding of the relation between variability in fetal and
infant growth and disease risk through the life course. Although new
assessment techniques have recently become available, body composition is rarely described in infants from low-income settings.
Objective: The aim of this study was to provide reference data for
fat mass (FM) and fat-free mass (FFM) from birth to the age of 6
mo from an urban African population.
Design: We conducted a prospective cohort study among infants
from Jimma, Ethiopia. FM and FFM were measured at birth and at
1.5, 2.5, 3.5, 4.5, and 6 mo of age with air-displacement plethysmography (ADP) validated against a stable isotope method in a subsample. Reference charts and reference tables with z scores and
percentiles for FM, FFM, FM index (FMI; in kg/m2), and FFM
index (FFMI: in kg/m2) were constructed with the lambdamu-sigma method.
Results: Body composition growth charts were based on a total of
2026 measurements of body composition obtained from 378 infants.
FM and FMI gain progressed in a logarithmic-shaped curve and
variation increased with increasing age, whereas FFM increased
in an almost linear manner with a minor deceleration at around 3
mo of age. The FFMI curve showed a very modest exponential
increase with age.
Conclusions: By presenting z scores and centile reference charts
for an apparently healthy urban Ethiopian infant population, this
study represents a first step toward providing reference data on FM
and FFM for an urban African context, which is important for
future clinical care and research. This study was registered at
www.controlled-trials.com as ISRCTN46718296. Am J Clin Nutr
2013;98:885–94
