Body composition prediction equations based on deuterium oxide dilution method in Mexican children: a national study.
OBJECTIVE
Obesity and undernutrition co-exist in many regions of Mexico. However, accurate assessments are difficult because epidemiological data on body composition are not available. The aim of this study was to facilitate assessments of body composition in Mexican school children of different geographical regions and ethnicity by developing equations for bioelectrical impedance and anthropometry based on deuterium oxide dilution.


METHODS
We evaluated 336 subjects (143 belonged to six major indigenous groups) from Northern, Central and Southern Mexico. We measured height (Ht), weight (Wt), tricipital skinfold (Tricp-SKF) and resistance (R) based on a bioimpedance analysis (BIA). Fat-free mass (FFM) and fat mass (FM) were estimated from measurements of total body water with the deuterium dilution technique.


RESULTS
The final BIA equation was FFM (kg)=0.661 × Ht²/R+0.200 × Wt-0.320. The R² was 0.96; the square root of the mean square error (SRMSE) was 1.39 kg. The final anthropometric equation was FM (kg)=-1.067 × sex+0.458 × Tricp-SKF+0.263 × Wt-5.407. The R² was 0.91; SRMSE was 1.60 kg. The BIA equation had a bias of 0.095 kg and precision of 1.43 kg. The anthropometric equation had a bias of 0.047 kg and precision of 1.58 kg.


CONCLUSIONS
We validated two equations for evaluating body composition in Mexican indigenous and non-indigenous children and youth from three main regions of the country. These equations provided reliable estimates and will promote a better understanding of both obesity and undernutrition.
Laboratorio de Composición Corporal y Gasto Energético, Centro de Investigación en Nutrición y Salud Pública, Facultad de Salud Pública y Nutrición, Universidad Autónoma de Nuevo León, Nuevo León, México.
E
E
Ramírez
M E
ME
Valencia
H
H
Bourges
T
T
Espinosa
S Y
SY
Moya-Camarena
G
G
Salazar
H
H
Alemán-Mateo
D000293:Adolescent; D000886:Anthropometry; D001823:Body Composition; D002648:Child; D002657:Child Development; D003430:Cross-Sectional Studies; D017666:Deuterium Oxide / Q000378:metabolism*; D017097:Electric Impedance; D005260:Female; D006306:Health Surveys; D006801:Humans; D007198:Indians, North American; D007201:Indicator Dilution Techniques; D008297:Male; D044342:Malnutrition / Q000453:epidemiology* / Q000208:ethnology; D008800:Mexico / Q000453:epidemiology; D008954:Models, Biological; D009765:Obesity / Q000453:epidemiology* / Q000208:ethnology; D015995:Prevalence; D012727:Sex Characteristics
D017666:Deuterium Oxide