Plasma zinc and hair zinc levels, anthropometric status and food intake of children in a rural area of Brazil / Zinco plasmático e zinco capilar, antropometria e consumo alimentar de crianças em uma região rural do Brasil

OBJECTIVE: The objective of this study was to investigate the levels of plasma zinc, hair zinc, growth and food consumption in children aged 6 to 24 months in a rural area of Diamantina (MG), Brazil. METHODS: Plasma and hair zinc concentrations were analyzed using flame atomic absorption spectrometry and neutron activation analysis, respectively. Weight-for-age, weight-for-height and height-for-age, expressed as Z-scores, were measured according to the World Health Organization reference curves. Dietary zinc intake was determined by a 3-day dietary recall filled out by the mother or guardian. RESULTS: Zinc deficiency was found in 11.2 percent and 16.8 percent of the children according to plasma zinc e hair zinc levels, respectively. Mean plasma zinc and hair zinc for children <11 (49) and >11 (127) months of age were 15.4 (SD=4.2) µmol L-1 and 139.5 (SD=72.1) µg g-1 and 16.0 (SD=4.5) µmol L-1 and 134.3 (SD=110.3) µg g-1, respectively. Anthropometric measurements showed that 8.0 percent, 6.8 percent and 3.4 percent of the children were underweight, stunted and wasted, respectively. The mean dietary intake of zinc was 3.2 (SD=2.3) mg/day. One-third of the children did not eat enough foods that contain zinc. There were no correlations among plasma zinc level, hair zinc level, anthropometric parameters and zinc intake. CONCLUION: The results demonstrate that zinc deficiency is a problem in the studied population, not just in malnourished children. Nutritional care should be provided for this population in order to improve their consumption of high-zinc foods and monitor zinc deficiency.

OBJETIVO: Investigar níveis plasmáticos de zinco, concentração de zinco capilar, crescimento físico, e consumo de zinco em crianças de 6 a 24 meses da região de Diamantina (MG), Brasil. MÉTODOS: As concentrações de zinco plasmático e zinco capilar foram analisadas empregando as técnicas de espectrometria atômica de absorção e de ativação neutrônica, respectivamente. Peso-para-idade, peso-para-altura e altura-para-idade, expressos em escore-Z, foram medidos, de acordo as curvas de referência da Organização Mundial de Saúde. O zinco dietético dos sujeitos foi avaliado a partir de três registros alimentares, preenchidos pelas mães ou responsáveis. RESULTADOS: A deficiência de zinco foi observada em 11,2 por cento e em 16,8 por cento das crianças, segundo os níveis de zinco plasmático e zinco capilar, respectivamente. As médias em crianças com 11 meses ou menos (49) e 11 (127) meses ou mais de idade para níveis de zinco plasmático e zinco em cabelos foram 15,4 (DP=4,2) µmol L-1 e 139,5 (DP= 72,1) µg g-1 e 16,0 (DP= 4,5) µmol L-1 e 134,3 (DP=110,3) µg g-1, respectivamente. Os resultados antropométricos mostraram que 8,0 por cento, 6,8 por cento e 3,4 por cento das crianças foram classificadas com baixo peso, baixa estatura e emagrecidas, respectivamente. A média do consumo dietético de zinco pelas crianças foi de 3,2 (DP=2,3) mg/zinco por dia, e um terço das crianças consumiam alimentos fonte de zinco abaixo do recomendado. Não houve correlação entre as variáveis zinco plasmático, zinco em cabelos, antropometria e consumo de zinco. CONCLUSÃO: Os resultados demonstram que a deficiência de zinco é um problema na população estudada, não somente nas crianças desnutridas. Atenção nutricional deverá ser direcionada a esta população, com o intuito de melhorar o consumo de alimentos ricos neste mineral e monitorar a deficiência de zinco.

THE LEVEL OF ZINC, COPPER, CALCIUM, PHOSPHORUS AND MAGNESIUM IN SERUM AND HAIR OF PREGNANT WOMEN AND THEIR NEWBORNS / 营养学报

A longitudinal study was carried out on zinc, copper, calcium, phosphorus and magnesium status of 104 normal primigravidas. The five elements in serum and hair of the mothers and their newborns were estimated with inductive coupled plasma emission spectroscopy. The results showed that the concentration of serum zinc, calcium, magnesium decreased gradually while copper and phosphorus increased remarkably in the course of pregnancy. The serum copper and phosphorus of cord blood were lower, zinc and calcium were higher than that of mothers' blood. The contents of hair zinc, copper, and phosphorus showed no differences but calcium and magnesium decreased gradually during pregnancy. Except that the level of copper in the newborns' hair was much lower, other elements were much higher than that in the mothers' hair.