Malnutrition continues to be a major public health problem throughout the developing world, particularly in southern Asia and sub-Saharan Africa.The high prevalence of bacterial and parasitic diseases in developing countries contributes greatly to malnutrition there.
Protein–energy malnutrition
In children, protein–energy malnutrition is defined by measurements that fall below 2 standard deviations under the normal weight for age (underweight), height for age(stunting) and weight for heigt (wasting).6 Wasting indicates recent weight loss, whereas stunting usually results from chronic weight loss..Protein– energy malnutrition usually manifests early, in children between 6 months and 2 years of age and is associated with early weaning, delayed introduction of complementary foods, a low-protein diet and severe or frequent infections. One essential aspect of severe protein–energy malnutrition is the fatty degeneration of such diverse organs as the liver and heart. This degeneration is not just a sign of severe malnutrition; it causes subclinical or overt cardiac insufficiency, especially when malnutrition is accompanied by edema. Most children with severe protein–energy malnutrition have asymptomatic infections because their immune system fails to respond with chemotaxis, opsonization and phagocytosis of bacteria , viruses or fungi. After insufficient supply of protein, carbohydrates and fat, the next major cause of protein–energy malnutrition is severe and chronic infections — particularly those producing diarrhea, but also other diseases such as helminthic infections. The pathologic changes include immunologic deficiency in the humoral and cellular subsystem from protein deficiency and lack of immune mediators. In sub-Saharan Africa and, increasingly, India, an additional concern is that many patients with severe malnutrition are also infected with HIV.55 The high mortality indicates a need for a systematic approach to the severely malnourished patient that goes beyond an appropriate diet. To reduce mortality, a complex management scheme is pivotal. In poor communities, the treatment of helminth infections 3 times per year improved child growth and development.15 Protein–energy malnutrition and diarrhea typically interact in a vicious cycle, but the control of diarrhea depends on more than medical help.
Micronutrient deficiencies
Micronutrient deficiencies affect at least 2 billion people worldwide. Iron is an essential part of hemoglobin, myoglobin and various enzymes. Its deficiency thus leads mainly to anemia,
but also to several other adverse effects.Lack of iodine reduces the production of thyroid hormone
and increases that of thyroid-stimulating hormone. As a result, the thyroid gland becomes hyperplastic and
goitrous, and hypothyroidism develops.3,7.Vitamin A deficiency contributes to anemia by immobilizing
iron in the reticuloendothelial system, reducinghemopoiesis and increasing susceptibility to infections. Vitamin A is essential for the functioning of the eyes as well as the immune system. Zinc is essential for the functioning of many enzymes and is thus involved in a large number of metabolic processes, including RNA and DNA synthesis. Foods with a high content of absorbable micronutrients are considered the best means for preventing micronutrient deficiencies.
Diet-based strategies are probably the most promising approach for a sustainable control of micronutrient deficiencies. Because malnutrition has many causes, only multiple and synergistic interventions embedded in true multisectoral programs can be effective. Nutrition education about locally available protein- and micronutrient-rich plants is particularly effective and sustainable.
Protein–energy malnutrition
In children, protein–energy malnutrition is defined by measurements that fall below 2 standard deviations under the normal weight for age (underweight), height for age(stunting) and weight for heigt (wasting).6 Wasting indicates recent weight loss, whereas stunting usually results from chronic weight loss..Protein– energy malnutrition usually manifests early, in children between 6 months and 2 years of age and is associated with early weaning, delayed introduction of complementary foods, a low-protein diet and severe or frequent infections. One essential aspect of severe protein–energy malnutrition is the fatty degeneration of such diverse organs as the liver and heart. This degeneration is not just a sign of severe malnutrition; it causes subclinical or overt cardiac insufficiency, especially when malnutrition is accompanied by edema. Most children with severe protein–energy malnutrition have asymptomatic infections because their immune system fails to respond with chemotaxis, opsonization and phagocytosis of bacteria , viruses or fungi. After insufficient supply of protein, carbohydrates and fat, the next major cause of protein–energy malnutrition is severe and chronic infections — particularly those producing diarrhea, but also other diseases such as helminthic infections. The pathologic changes include immunologic deficiency in the humoral and cellular subsystem from protein deficiency and lack of immune mediators. In sub-Saharan Africa and, increasingly, India, an additional concern is that many patients with severe malnutrition are also infected with HIV.55 The high mortality indicates a need for a systematic approach to the severely malnourished patient that goes beyond an appropriate diet. To reduce mortality, a complex management scheme is pivotal. In poor communities, the treatment of helminth infections 3 times per year improved child growth and development.15 Protein–energy malnutrition and diarrhea typically interact in a vicious cycle, but the control of diarrhea depends on more than medical help.
Micronutrient deficiencies
Micronutrient deficiencies affect at least 2 billion people worldwide. Iron is an essential part of hemoglobin, myoglobin and various enzymes. Its deficiency thus leads mainly to anemia,
but also to several other adverse effects.Lack of iodine reduces the production of thyroid hormone
and increases that of thyroid-stimulating hormone. As a result, the thyroid gland becomes hyperplastic and
goitrous, and hypothyroidism develops.3,7.Vitamin A deficiency contributes to anemia by immobilizing
iron in the reticuloendothelial system, reducinghemopoiesis and increasing susceptibility to infections. Vitamin A is essential for the functioning of the eyes as well as the immune system. Zinc is essential for the functioning of many enzymes and is thus involved in a large number of metabolic processes, including RNA and DNA synthesis. Foods with a high content of absorbable micronutrients are considered the best means for preventing micronutrient deficiencies.
Diet-based strategies are probably the most promising approach for a sustainable control of micronutrient deficiencies. Because malnutrition has many causes, only multiple and synergistic interventions embedded in true multisectoral programs can be effective. Nutrition education about locally available protein- and micronutrient-rich plants is particularly effective and sustainable.
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