parameters of disease incidence, duration, and severity. Although the impaired immune function that is secondary to malnutrition predisposes infants and children to infectious illness, poverty, inadequate food availability, inappropriate foods, and increased transmission of pathogens are each determinants of the high rates of enteric illness in economically developing countries.
Breastfeeding is the single most effective nutritional strategy for protecting infants against enteric disease. Three mechanisms have been proposed by which human milk constituents protect the infant from infection. Two are based on the immunologic constituents of human milk and the third is its high nutrient value. The practice of breastfeeding itself provides a fourth mechanism because it decreases exposure to pathogens.
The protective effects of the constituents of human milk and of the practice of breastfeeding suggest that enhancement of lactation performance should lengthen the time before supplementary foods are required to meet the nutrient requirements of infants and maximize the protection against enteric disease. Available studies suggest that maternal nutritional status influences the volume of milk that is produced and may influence its composition. The effect of maternal nutritional status on milk volume suggests that nutritional status also influences the duration of lactation.
Emphasis is given to the duration of lactation because supplementary and weaning foods can be sources of the transmission of enteric pathogens. Interventions that will decrease their role in the potential transmission of enteropathogens include improved personal hygiene, reduction of storage of weaning foods, improvement of food storage conditions, and the use of processed foods that are resistant to bacterial proliferation.
Such interventions must be accompanied by efforts to improve the nutritional quality of supplementary and weaning foods. Several processes exist for improving the caloric density of foods, enhancing nutrient composition and/or storage stability: e.g., fermentation, germination, and milling and dry cooking (roasting and extrusion) can be used to provide weaning foods with some of the desired characteristics. The selection of either large-or small-scale industrial or home-based technologies should be made after a careful assessment of the costs (e.g., capital and labor) and the suitability of the final product within the context of specific cultures.
The three principal objectives of nutritional interventions intended to reduce diarrheal disease in children are the enhancement of the child's nutritional status, reduction of the risk of infection, and a reduction in the mortality and severity of morbidity following infection. Two general interventions are recommended: