The Reference Child and Adolescent Models of Body Composition: A Contemporary Comparison^a

Abstract

Changes in the relative proportions of bone, muscle, water, visceral tissues, and body fat occur during growth. In the 1980s, reference models of body composition for children and adolescents were constructed by adjusting data on total body water (TBW), total body potassium (TBK), and regional bone mineral (BMC) data from several different Caucasian populations. In our study, we measured TBW, TBK, and total body BMC in 856 healthy European‐American, African‐American, and Mexican‐American children. When we reconstructed the reference models using our contemporary data, we found that the body's bone, protein, and fat compartments are slightly but significantly different from the earlier models. Our study provides the range of normal body composition of healthy children, aged 5–18 years, and accounts for differences related to gender and ethnicity.

Lysine requirement of healthy school-age children determined by the indicator amino acid oxidation method

“…Their anthropometric measures (Table 1) were within the normal range for age (22,23) and did not change during the course of the study. Similarly, energy and protein intakes of the subjects were adequate.…”

“…The individual amino acid requirements for growth were recently calculated from the rates of protein deposition for children of different age groups (23,27), the amino acid composition of whole-body protein (28), and the incremental efficiency of protein utilization (2). The amount of lysine required for growth in 9-13-y-old children was calculated as the product of the rate of protein deposition (49 mg ⅐ kg Ҁ1 ⅐ d Ҁ1 ) and lysine composition of the whole body (0.073%) divided by 0.58, the efficiency of dietary protein utilization, to yield a value of 6.1 mg ⅐ kg Ҁ1 ⅐ d Ҁ1 .…”

Índice de conicidade como preditor de alterações no perfil lipídico em adolescentes de uma cidade do Nordeste do Brasil

“…Esse resultado pode estar associado ao fato de que adolescentes do sexo masculino, em geral, apresentam tendência a acumular uma mario quantidade de gordura na região abdominal 43,44,45 . Mesmo demonstrando uma redução da gordura corporal nessa faixa etária 46,47 , em adolescentes do sexo masculino, estima-se que valores plenos de massa livre de gordura sejam atingidos dois a três anos mais tarde que as meninas 47,48 .…”

“…Este índice tem sido foco de diversos estudos com intuito de avaliar a sua possível relação com variáveis consideradas como de risco para o desenvolvimento de doenças cardiovasculares 11,12,13,14,15,16 , tendo em vista que representa um bom indicador de obesidade, sobretudo central 17,18 .…”

Association of Chronic Kidney Disease with Muscle Deficits in Children

“…It should be noted that fat-free mass measured by DXA assumes normal hydration of lean tissue; fluid overload will result in overestimation of fat-free mass and volume depletion in underestimation. DXA is a precise (coefficient of variation [CV] 1% to 4%) 55 method used extensively to describe age-, sex-, race-, and pubertal maturation-related variability in body composition. 56 -59 DXA-derived appendicular lean soft tissue mass has been previously demonstrated to reflect skeletal muscle.…”