Impact of dietary iron intake on anaemia in Tanzanian schoolchildren

Abstract

Objective. To investigate the nutritional relationship between dietary intake and prevalence of anaemia among Tanzanian schoolchildren. Methods. Dietary intakes of 101 schoolchildren aged 7 - 12 years were assessed using a pre-tested food frequency questionnaire. Haemoglobin (Hb), haematocrit, erythrocyte protoporphyrin (EP) and serum ferritin (SF) were used to determine their anaemia and iron status. Other socio-economic variables were collected using a profile questionnaire. Results. Significantly lower intake of iron was seen in 48% of schoolchildren with Hb < 11.5 g/dl (anaemic) compared with those who were normal. Total iron intake was 22 ± 7 and 27 ± 13 mg/day respectively (p < 0.05). There was a general poor intake of iron from animal sources in all children. A higher iron intake was found in schoolchildren with normal iron status (by EP and SF levels) than in those who were not normal (26 ± 11 mg/day v. 22 ± 9 mg/day, p < 0.05). Iron deficiency was found in 45% of schoolchildren (N = 80) and 31% were categorised as having iron deficiency anaemia. The mean energy intake in boys was higher than in girls (2 150 ± 770 v. 1 830 ± 895 kcal/day respectively). Boys also had a higher intake of ascorbic acid (50 ± 32 v. 31 ± 23 mg/day, p > 0.05). In stepwise multiple regression analysis, daily iron intake remained the most significant nutrient predicting for Hb status. There was a significant correlation between iron intake and serum ferritin (r = 0.233, p < 0.05). Conclusion. Iron intake in this Tanzanian community is inadequate for maintaining normal iron nutrition. The factors contributing to the inadequacy include consumption of foods with low iron bioavailability. Food-based intervention should be one of the important strategies for reducing the magnitude of the problem of anaemia in this community.