Measurement of body composition in teenagers: comparison between methods

Abstract

The application of stable isotopes of deuterium (2H) and assessment of oxygen-18 (18O) can be used in body composition and total energy expenditure and, due to its innocuity, it is safe to be used in children and teenagers. Assessing the body composition may favor the identification of health risks associated with high or low body fat levels; the nutritional status of patients with active metabolically diseases and a composition associated with body development, according to body maturity and age group. The search for fat to estimate the percentage of methods in adolescents can present the body health including the identification, coping and obesity prevention. The main objective of this work is to compare the isotopic method with bioimpedance and simple predictive formulas to determine the body composition of male genders with different biotypes. Adolescents between 14 and 19 years of age will be selected: 26 obese adolescents and 26 eutrophics who practice regular physical activity. By consuming 0.12g of 2H at 99,8 atoms% per kilogram of body water, will be taken samples of urine and saliva samples for the isotopic method. The result of the isotopic analysis, anthropometric measurements (weight, height, and skinfolds), and bioelectrical impedance (Biodynamics Model 450® and SECA mBCA 525®)will be compared. A last the volunteers will answer the questionnaire on habitual food consumption, and frequency of physical activity and will perform the breath test, used as a marker of sugar consumption for complementary analysis.(AU)