Micronutrient deficiencies in South African infants and the effect of a micronutrient-fortified complementary food on their nutritional status, growth and development

Abstract

Consequences of micronutrient deficiencies in infants often include linear growth retardation, impaired psychomotor development and reduced appetite. Fortification of complementary food is one way of addressing micronutrient deficiencies in this age group. Knowledge about these deficiencies, food consumption patterns and appetite in infants is essential in planning micronutrient fortification intervention studies. In this thesis four studies are described, two of which studied the prevalence of micronutrient deficiency and linear growth retardation in rural and urban disadvantaged South African infants. The third study determined the adequacy of the appetite of infants at the age of 6 months. The final study is an intervention study with the aim to study the effect of a micronutrient fortified complementary food on the nutritional status, growth and development of 6-12-month-old poor urban infants.The results from the first two studies showed a high prevalence of vitamin A, iron and zinc deficiency in both rural and urban infants. The low socio-economic status of the urban community and sub-optimal feeding practices may explain the similarity of deficiencies observed between rural and urban infants. The third study demonstrates that appetite was adequate in infants at the age of 6 months and not yet affected by micronutrient deficiencies. The consumption of a micronutrient-fortified complementary food appeared to reduce the decline in both serum retinol and iron concentrations in the experimental group. No effect was observed on serum zinc concentration, linear growth and psychomotor development.In conclusion, the findings of this study demonstrate similar levels of nutritional deficiencies in both poor urban and rural children. Significant differences between urban disadvantaged coloured and black infants with respect to micronutrient deficiencies and linear growth exist. This highlights the importance of including assessment of micronutrient status in addition to anthropometric measurements when assessing nutritional status. The observation of an adequate appetite in infants at the age of 6 months is important for the introduction of micronutrient-fortified complementary food. The observed positive effect of a micronutrient-fortified complementary food on serum retinol and iron concentrations in 6-12-month-old infants should be investigated further.</p