Adequacy of micronutrient content of south eastern Nigerian meals in meeting the nutritional needs of vulnerable groups

Abstract

The Zinc (Zn), iron Fe) and copper (Cu) contents and their bioavailability in south-eastern Nigerian meals were evaluated. Their adequacy in meeting the nutritional requirements of pregnant and lactating women and preschool children were determined. Mineral content was determined using atomic absorption spectrophotometer after dry ashing. Phytate was determined by the ion exchange method. The bioavailability of Zn was evaluated using the phytate: Zn molar ratio (PZMR). Bioavailability of iron was determined by the in vitro procedure involving a simulated gastrointestinal digestion followed by dialysis. Portion sizes of meals consumed by these vulnerable groups were obtained during an interview and validated using data obtained from food consumption surveys. The amount of Zn and Fe in such portions were calculated and compared with the recommended intakes. Zn content of the meals ranged from 1.18mg to 4.99mg/100g, Fe from 1.10mg to 3.31mg/100g and Cu from 0.03mg to 0.21mg/100g edible portion or as consumed. Phytate levels varied from 4.11mg to 53.05mg/100g. The PZMR of the meals and serving portions were <10. Bioavailability of iron from the meals varied from 6-26%, while that of Cu varied from 1-59%. The diets were found to contain enough micronutrients to meet nutritional requirement of the vulnerable groups. However, the amount of bio-available Fe and Cu were grossly inadequate for all the groups. The results showed that Zn deficiency in Southern Nigerian may not be due to inadequate intake or phytic acid content of foods but probably due to interaction with other dietary components. This study highlights the need for dietary modification and other nutrition intervention for the Nigerian population and particularly the vulnerable groups..

Keywords: Micronutrients, diets, vulnerable groups, Nigeria

Agro-Science Vol. 3 (2) 2006: pp. 37-44