Maternal and child undernutrition and micronutrient deficiencies affect approximately half of the world’s population. These conditions include intrauterine growth restriction (IUGR), low birth weight, protein-energy malnutrition, chronic energy deficit of women, and micronutrient deficiencies. Although the rates of stunting or chronic protein-energy malnutrition are increasing in Africa, the absolute numbers of stunted children are much higher in Asia. The four common micronutrient deficiencies include those of iron, iodine, vitamin A, and zinc. All these conditions are responsible directly or indirectly for more than 50% of all under-5 deaths globally. According to more recent estimates, IUGR, stunting and severe wasting are responsible for one third of under-5 mortality. About 12% of deaths among under-5 children are attributed to the deficiency of the four common micronutrients. Despite tremendous progress in different disciplines and unprecedented improvement with many health indicators, persistently high undernutrition rates are a shame to the society. Human development is not possible without taking care to control undernutrition and micronutrient deficiencies. Poverty, food insecurity, ignorance, lack of appropriate infant and young child feeding practices, heavy burden of infectious illnesses, and poor hygiene and sanitation are factors responsible for the high levels of maternal and child undernutrition in developing countries. These factors can be controlled or removed by scaling up direct nutrition interventions and eliminating the root conditions including female illiteracy, lack of livelihoods, lack of women’s empowerment, and poor hygiene and sanitation.
In the year 2011, 6.9 million children under the age of 5 years died worldwide, one third of them related to increased susceptibility to illnesses due to undernutrition. An estimated 178 million children under 5 years are stunted, 55 million are wasted, and 19 million of these are severely affected and are at a higher risk of premature death, the vast majority being from sub-Saharan Africa and South-Central Asia. Globally, over 2 billion people are at risk for vitamin A, iodine, and/or iron deficiency. Other micronutrient deficiencies of public health concern include zinc, folate, and the B vitamins. The risk factors for undernutrition include low birth weight, inadequate breastfeeding, improper complementary feeding, and recurrent infections. Infectious diseases often coexist with micronutrient deficiencies and exhibit complex interactions leading to the vicious cycle of malnutrition and infections. Diarrhea along with the poor selection and intake of complementary food are the major contributors to undernutrition. Possible strategies to combat malnutrition include promotion of breastfeeding, dietary supplementation of micronutrients, prevention of protein-energy malnutrition, and improvement in the standard of preparation and hygiene of available weaning foods. The universal coverage with the full package of these proven interventions at observed levels of program effectiveness could prevent about one quarter of child deaths under 36 months of age and reduce the prevalence of stunting at 36 months by about one third. The median coverage rate of interventions along the continuum of care for Countdown countries has however been 6 80% for vaccination and vitamin A supplementation. However, for several interventions, including early initiation and exclusive breastfeeding below 6 months of age and case management of childhood illnesses, the median coverage rate hovers at or below 50%. This suggests that interventions requiring strong health systems or behavior change appear to be stalled and need to be re-examined to find more effective
ways of delivery.
This article provides an overview of child feeding recommendations and how these relate to actual practice and dietary adequacy, primarily in developing countries. From birth to 6 months, recommendations focus on optimal breastfeeding practices, although these are still suboptimal in about one third of infants in developing countries. From 6 months of age, breast milk can no longer meet all the nutrient requirements of the child, so from 6 months through at least 24 months, the recommendation is to continue breastfeeding but gradually introduce complementary foods. In poorer populations, the available foods for complementary feeding are primarily cereals and legumes, to which small amounts of fruits and vegetables are added, and even less animal source foods. Based on intake data from infants and preschoolers, it is evident that usual diets typically fall far short of supplying micronutrient needs. By adding more fruits, vegetables, and animal source foods the diet can be improved. Intervention studies show that increasing animal source food intake improves growth, muscle mass, and cognitive function of school children. Milk and dairy product intakes are correlated with greater child growth in many studies, even in industrialized countries. However, for many families, substantially improving children’s diets by providing higher quality foods is often financially unrealistic. Newer approaches to home fortification of children’s foods using micronutrient powders or lipid-based nutrient supplements hold great potential to prevent micronutrient deficiencies at reasonable cost, thus preventing the adverse consequences of these deficiencies for child development.
The interaction of nutrition and infections is known by experience by generations of medical doctors. Before the era of antibiotics, diet was an integral part of the management of infections. Now, it is necessary to take a fresh look at this interaction as the understanding of immune response has expanded considerably. Comparatively little research has addressed the impact of nutrition interventions on the management of infectious diseases. Most observations of the interaction between nutrition and infections are epidemiological in character. This holds especially true for measles as well as for tuberculosis. In AIDS, the deterioration of the nutritional status is an indicator of disease progression. Infections in undernourished children are a common cause of death, and taking this finding into account helps to reduce the case fatality rate in severely malnourished patients. Regarding
the immune response, cellular as well as soluble components are affected by deficiencies of single nutrients or general undernutrition. The immunosuppressive effect of undernutrition starts during intrauterine life already: maternal nutrition status has been shown to impact on immune function in adult animals. Recent research suggests that not only undernutrition but also caloric overnutrition impacts on immune response to infections and immunization. This is partly due to the chronic inflammatory activity of the adipose tissue and partly due to neuroendocrine alterations. Infectious diseases also impact on the nutritional status, either specifically or through unspecific mechanisms, such as anorexia, tachypnea, and vomiting.