Erythrocytary Zinc and the Infant Growth Profile in Northeast Brazil

Abstract

This study evaluated nutritional status linked to zinc levels in 239 randomly selected children at crèches in Teresina, Brazil, aged 3 to 6. Blood samples were collected after fasting of 10 h. Erythrocytary zinc levels were determined through flame atomic absorption spectrophotometry. Zinc deficiency was determined as below 40 microg Zn/g Hb. Infant linear growth was evaluated measuring weight and height, and nutritional status by height/age, weight/height, and weight/age indices, expressed as Z scores, in line with the National Center for Health Statistics. The mean zinc concentration was 35.50 +/- 10.95 microg Zn/g Hb. Zinc distribution in the 10, 50, 75, and 90 percentiles was 24.73 microg Zn/g Hb, 35.45 microg Zn/g Hb, 40.73 microg Zn/g Hb and 52.77 microg Zn/g Hb, respectively. Based on this distribution, normal values were found only from the 75th percentile and above. Since the cutoff point adopted was 40 microg Zn/g Hb, the prevalence of zinc deficiency was 74.3%. As for growth profile, 8.4% were chronically malnourished, although the statistical association between linear impairment and nutritional status regarding zinc was insignificant. The study revealed that an important segment of the infant population was mineral deficient; however, the degree of deficiency did not influence growth profiles.

Brazilian studies on zinc deficiency and supplementation: emphasis on children

“…The quality criteria in which articles presented the greatest limitation were, in particular, proof of representativeness of the sample studied in relation to the study population (in observational and experimental studies); definition of main confounding factors (in observational studies) and description of loss of participant (in observational and experimental studies). Considering that all the articles had an average or high quality and that the main risks of bias were associated with the analysis of loss of participants and confounding factors, without negative effects on the objectives of the review, we decided to systematize all the studies The analysis of sample representativeness indicates that 15 studies 16,17,19,20,29,31,34,36,[38][39][40]42,[44][45][46] used a representative sample and random selection of participants, five 15,18,21,22,37 studied a large population percentage and ten 23,24,26,27,30,32,33,35,41,43 studied populations with no characteristic of representativeness. With the exception of two studies, 25,30 representativeness was guaranteed in all others that focused on preschool children (Tables 1 and 2).…”

“…The most commonly used biochemical indicators of zinc nutritional status were plasma zinc (n = 6), 15,18,24,27,28,30 serum zinc (n=5) 17,19,[21][22][23] and erythrocyte zinc (n = 3). 15,20,23 In order to evaluate dietary zinc intake, the 24-hour recall was the most commonly used instrument. The association of zinc nutritional status with growth, childhood infectious diseases and status of other …”

“…20 Prevalence of 0% 19 and 0.5% 22 were found in studies conducted in Ribeirão Preto, SP. The highest prevalence was found in Teresina, 20 Northeast Region of Brazil. In other populations, prevalence of zinc deficiency showed more similar values, ranging from 7.5% 21 to 16.8%.…”

“…18,19,21,22,25,30 were performed in the Southeast, eight 15,[17][18][19][20][21][22]30 showed results of zinc deficiency prevalence using biochemical parameters, and five [16][17][18]25,29 presented results of zinc dietary inadequacy.…”

Isolated and combined prevalence of anemia, vitamin A deficiency and zinc deficiency in preschool children 12-72 months for the government of Paraíba

“…Em relação à deficiência de zinco, estudos realizados no Brasil apontam baixos níveis de zinco na população infantil [23][24][25] , assim como encontrado nesta pesquisa (13,8%). Ressalta-se que os dados de prevalência de deficiência de zinco no Brasil e no mundo ainda são escassos, devido, provavelmente, às dificuldades técnicas para obtenção de um marcador biológico confiável constataram uma tendência crescente nas concentrações médias de hemoglobina com o aumento da idade.…”