RESUMO
Iron is an essential element for human life and its nutritional status in the human body is directly linked to human health. More than 1015 atoms of iron per second are necessary for the maintenance of haemoglobin formation. To predict iron bioavailability three approaches are normally employed: (a) faecal recovery; (b) plasma appearance; and (c) erythrocyte incorporation (the most used). Isotope Pattern Deconvolution (IPD) is a mathematical tool that allows the isolation of distinct isotope signatures from mixtures of natural abundance and enriched tracers. In this work we propose a novel strategy to assess erythrocyte iron incorporation, based on the use of an iron stable isotope (57Fe) and the IPD concept. This strategy allows direct calculation of the exogenous concentration of 57Fe incorporated into RBCs after supplementation. In this way, to determine the mass of iron incorporated into erythrocytes, the unique prediction that must be made is the blood volume, estimate to reproduce the natural dilution of the tracer (57Fe) in the blood. This novel bioanalytical approach was applied for the measurements of iron incorporation and further iron absorption studies in humans, using a group of twelve healthy participants, that should be further evaluated for the assessment of other chemical elements that could be of health concerns and directly impact society.
Assuntos
Eritrócitos , Ferro , Humanos , Ferro/metabolismo , Isótopos de Ferro/metabolismo , Eritrócitos/metabolismo , Plasma , Disponibilidade BiológicaRESUMO
This article aims to present methodological aspects on the collection, analyses, coverage, challenges, and the lessons learned from laboratory assessment of micronutrients on the Brazilian National Survey on Child Nutrition (ENANI-2019). This is a household survey on a probability sample of children under five years of age from 123 Brazilian municipalities in all 26 states and the Federal District. Blood samples were drawn by venipuncture at the homes of children 6 to 59 months of age. This procedure was performed by experienced phlebotomists from the laboratories located in the selected municipalities and scheduled in advance. Blood and serum levels were measured for biomarkers of nutritional status, using the services of a clinical test laboratory with nationwide coverage, for the following micronutrients: iron (hemoglobin and ferritin), zinc, selenium, folic acid, and vitamins A, B1, B6, B12, D, and E. C-reactive protein was analyzed as a marker of inflammation. A barcode identifier was used to track the blood samples and to link the biochemical test results to the other data collected in the survey. A total of 14,558 children were studied. Of the 12,598 eligible children, 8,829 (70.1%) had blood samples drawn. Of the total number of children who had samples drawn, 91.8% (n = 8,025) have results for at least nine of the 12 analyses performed. Coverage of the analysis varied from 95% (for vitamins A and E) to 84.2% (for folic acid). Aliquots of whole blood and serum were stored in a biorepository for future analyses. The results of this pioneering study in the country will back the formulation and, when necessary, the reorientation of public policies in food and nutrition.
Assuntos
Micronutrientes , Oligoelementos , Brasil , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Humanos , Estado NutricionalRESUMO
This article aims to present methodological aspects on the collection, analyses, coverage, challenges, and the lessons learned from laboratory assessment of micronutrients on the Brazilian National Survey on Child Nutrition (ENANI-2019). This is a household survey on a probability sample of children under five years of age from 123 Brazilian municipalities in all 26 states and the Federal District. Blood samples were drawn by venipuncture at the homes of children 6 to 59 months of age. This procedure was performed by experienced phlebotomists from the laboratories located in the selected municipalities and scheduled in advance. Blood and serum levels were measured for biomarkers of nutritional status, using the services of a clinical test laboratory with nationwide coverage, for the following micronutrients: iron (hemoglobin and ferritin), zinc, selenium, folic acid, and vitamins A, B1, B6, B12, D, and E. C-reactive protein was analyzed as a marker of inflammation. A barcode identifier was used to track the blood samples and to link the biochemical test results to the other data collected in the survey. A total of 14,558 children were studied. Of the 12,598 eligible children, 8,829 (70.1%) had blood samples drawn. Of the total number of children who had samples drawn, 91.8% (n = 8,025) have results for at least nine of the 12 analyses performed. Coverage of the analysis varied from 95% (for vitamins A and E) to 84.2% (for folic acid). Aliquots of whole blood and serum were stored in a biorepository for future analyses. The results of this pioneering study in the country will back the formulation and, when necessary, the reorientation of public policies in food and nutrition.
O objetivo deste artigo é apresentar os aspectos metodológicos referentes à coleta e análise de dados laboratoriais do Estudo Nacional de Alimentação e Nutrição Infantil (ENANI-2019), a cobertura das análises laboratoriais, os desafios enfrentados e as lições aprendidas. Trata-se de um inquérito populacional de base domiciliar de crianças menores de cinco anos realizado em 123 municípios dos 26 estados da Federação e o Distrito Federal. A coleta de sangue por punção venosa foi realizada em domicílio em crianças com idade entre 6 e 59 meses, por coletador experiente de laboratório(s) existente(s) nos municípios amostrados. Foram determinadas as concentrações sanguíneas e séricas de biomarcadores do estado nutricional utilizando os serviços de um laboratório de análises clínicas com abrangência nacional para os seguintes micronutrientes: ferro (hemoglobina e ferritina), zinco, selênio, ácido fólico, vitaminas A, B1, B6, B12, D e E. A proteína C reativa foi analisada como marcador de inflamação. Um código de barras identificador das amostras de sangue foi utilizado para o rastreio da amostra e para a junção dos resultados dos exames bioquímicos com os demais dados coletados na pesquisa. Foram estudadas 14.558 crianças. Das 12.598 elegíveis, 8.829 (70,1%) realizaram coleta de sangue. Do total de crianças que realizaram coleta de sangue, 91,8% (n = 8.025) têm resultados para pelo menos nove das 12 análises realizadas. A cobertura por análise variou de 95% (para vitaminas A e E) a 84,2% (para ácido fólico). Os resultados deste estudo pioneiro subsidiarão a formulação e, quando for o caso, o redirecionamento de políticas públicas de alimentação e nutrição.
El objetivo de este artículo es presentar aspectos metodológicos, respecto a la recogida y análisis de datos de laboratorio del Estudio Nacional de Alimentación y Nutrición Infantil (ENANI-2019), así como la cobertura de los mismos, los desafíos enfrentados y lecciones aprendidas. Se trata de una encuesta poblacional de base domiciliaria con niños menores de cinco años, realizada en 123 municipios de los 26 estados de la Federación y el Distrito Federal. La recogida de sangre por punción venosa se realizó en domicilios con niños, de edades comprendidas entre los 6 y los 59 meses, con la intervención de un flebotomista con experiencia en laboratorio(s) existente(s) en los municipios de muestra. Se determinaron las concentraciones sanguíneas y séricas de biomarcadores del estado nutricional, utilizando los servicios de un laboratorio de análisis clínicos con alcance nacional para los siguientes micronutrientes: hierro (hemoglobina y ferritina), zinc, selenio, ácido fólico, vitaminas A, B1, B6, B12, D y E. La proteína C reactiva se analizó como marcador de inflamación. Un código de barras identificador de las muestras de sangre se utilizó para el rastreo de la muestra y para la conjunción de los resultados de los exámenes bioquímicos con los demás datos recogidos en la investigación. Se estudiaron 14.558 niños. De los 12.598 elegibles, a 8.829 (70,1%) se les sacó sangre. Del total de niños, a quienes se les tomó muestras de sangre, un 91,8% (n = 8.025) obtuvieron resultados para por lo menos nueve de los 12 análisis realizados. La cobertura por análisis varió de un 95% (para vitaminas A y E), a un 84,2% (para ácido fólico). Los resultados de este estudio pionero apoyarán la formulación y, cuando fuera necesario, la redirección de políticas públicas de alimentación y nutrición.
Assuntos
Humanos , Pré-Escolar , Criança , Oligoelementos , Micronutrientes , Brasil , Fenômenos Fisiológicos da Nutrição Infantil , Estado NutricionalRESUMO
BACKGROUND: The aims were to evaluate the nutritional status, central adiposity, and physical growth profile of adolescents in a sports-oriented public school (SOPS) and to describe the results considering the Brazilian and American adolescents' survey studies. METHODS: This study was a dynamic cohort, performed in 2012-2013 and 2015. 1,082 adolescent athletes (11-16 years old) participated. Anthropometric data (height [H], weight, and waist circumference [WC]) were collected yearly. The nutritional status was assessed using BMI Z-score; trunk fat, using WC and WC/H ratio; and growth, using height z-score. The SOPS results were described considering data from the Brazilian Household Budget Survey (HBS-Southeast region) and the National Health and Nutrition Examination Survey (NHANES). Anthropometric data was compared using linear mixed effects regression models, considering sex, age group and time. RESULTS: Considering height Z-score and BMI Z-score values, none of the adolescents in the SOPS had short stature or underweight, and the obesity prevalence was approximately 1% throughout the study. HBS survey revealed 3.4% of obesity prevalence in adolescents (11-16 years old). Considering age and time, significant differences in WC for both sexes were observed. However, considering NHANES data, our participants were classified in P5-25. CONCLUSIONS: These results suggest that the nutritional status of adolescents in the SOPS was good, obesity prevalence was 1% and WC measurement was within P5-25 considering NHANES data. This supports the public policies encouraging involvement in sports at school, which should be one of the priorities in the health promotion agenda, reducing the development of future chronic diseases.