Human nutrition in the developing world. Part III. Disorders of malnutrition. Chapter 1. 2. Protein- energy malnutrition. Protein- energy malnutrition (PEM) in young children is currently the most important nutritional problem in most countries in Asia, Latin America, the Near East and Africa. Energy deficiency is the major cause. No accurate figures exist on the world prevalence of PEM, but World Health Organization (WHO) estimates suggest that the prevalence of PEM in children under five years of age in developing countries has fallen progressively, from 4. However, in some regions this fall in percentage has not been as rapid as the rise in population; thus in some regions, such as Africa and South Asia, the number of malnourished children has in fact risen. In fact the number of underweight children worldwide has risen from 1. Failure to grow adequately is the first and most important manifestation of PEM. It often results from consuming too little food, especially energy, and is frequently aggravated by infections. A child who manifests growth failure may be shorter in length or height or lighter in weight than expected for a child of his or her age, or may be thinner than expected for height. The conceptual framework described in Chapter 1 suggests that there are three necessary conditions to prevent malnutrition or growth failure: adequate food availability and consumption; good health and access to medical care; and adequate care and feeding practices. If any one of these is absent, PEM is a likely outcome. The term protein- energy malnutrition entered the medical literature fairly recently, but the condition has been known for many years. In earlier literature it was called by other names, including protein- calorie malnutrition (PCM) and protein- energy deficiency. The term PEM is used to describe a broad array of clinical conditions ranging from the mild to the serious. At one end of the spectrum, mild PEM manifests itself mainly as poor physical growth in children; at the other end of the spectrum, kwashiorkor (characterized by the presence of oedema) and nutritional marasmus (characterized by severe wasting) have high case fatality rates. It has been known for centuries that grossly inadequate food intake during famine and food shortages leads to weight loss and wasting and eventually to death from starvation. However, it was not until the 1. Cicely Williams, working in Ghana, described in detail the condition she termed . In the 1. 95. 0s kwashiorkor began to get a great deal of attention. It was often described as the most important form of malnutrition, and it was believed to be caused mainly by protein deficiency. The solution seemed to be to make more protein- rich foods available to children at risk. This stress on kwashiorkor and on protein led to a relative neglect of nutritional marasmus and adequate food and energy intakes for children. The current view is that most PEM is the result of inadequate intake or poor utilization of food and energy, not a deficiency of one nutrient and not usually simply a lack of dietary protein. It has also been increasingly realized that infections contribute importantly to PEM. Gold is a chemical element with symbol Au (from Latin: aurum) and atomic number 79. In its purest form, it is a bright, slightly reddish yellow, dense, soft. Learn everything about Luminae, the dedicated restaurant for Celebrity's Suite Class that gives a truly VIP feel and the rarity of an intimate dining space. If you're an ocean cruiser planning your first river cruise, here's our list of things you should know, from ship and cabin size to entertainment and tour options. In 2012, Brazil’s Behold Studios released Knights of Pen and Paper, a video game that captured the experience of a bunch of players sitting around a table playing a. Nutritional marasmus is now recognized to be often more prevalent than kwashiorkor. It is unknown why a given child may develop one syndrome as opposed to the other, and it is now seen that these two serious clinical forms of PEM constitute only the small tip of the iceberg. In most populations studied in poor countries, the point prevalence rate for kwashiorkor and nutritional marasmus combined is 1 to 5 percent, whereas 3. PEM, diagnosed mainly on the basis of anthropometric measurements. Causes and epidemiology. PEM, unlike the other important nutritional deficiency diseases, is a macronutrient deficiency, not a micronutrient deficiency. Although termed PEM, it is now generally accepted to stem in most cases from energy deficiency, often caused by insufficient food intake. Energy deficiency is more important and more common than protein deficiency. It is very often associated with infections and with micronutrient deficiencies. Inadequate care, for example infrequent feeding, may play a part. The cause of PEM (and of some other deficiency diseases prevalent in developing countries) should not, however, be viewed simply in terms of inadequate intake of nutrients. For satisfactory nutrition, foods and the nutrients they contain must be available to the family in adequate quantity; the correct balance of foods and nutrients must be fed at the right intervals; the individual must have an appetite to consume the food; there must be proper digestion and absorption of the nutrients in the food; the metabolism of the person must be reasonably normal; and there should be no conditions that prevent body cells from utilizing the nutrients or that result in abnormal losses of nutrients. Factors that adversely influence any of these requisites can be causes of malnutrition, particularly PEM. The aetiology, therefore, can be complex. Certain factors that contribute to PEM, particularly in the young child, are related to the host, the agent (the diet) and the environment. The underlying causes could also be categorized as those related to the child's food security, health (including protection from infections and appropriate treatment of illness) and care, including maternal and family practices such as those related to frequency of feeding, breastfeeding and weaning. Some examples of factors involved in the aetiology of PEM are. Failure of breastfeeding because of death of the mother, separation from the mother or lack of or insufficient breastmilk may be causes in poor societies where breastfeeding is often the only feasible way for mothers to feed their babies adequately. An underlying cause of PEM is any influence that prevents mothers from breastfeeding their newborn infants when they live in households where proper bottle- feeding may be difficult or hazardous. Therefore promotion of infant formula and insufficient support of breastfeeding by the medical profession and health services may be factors in the aetiology of marasmus. Prolonged exclusive breastfeeding without the introduction of other foods after six months of age may also contribute to growth faltering, PEM and eventually nutritional marasmus. The view that kwashiorkor is the result of protein deficiency and nutritional marasmus the result of energy deficiency is an oversimplification, as the causes of both conditions are complex. Both endogenous and exogenous causes are likely to influence whether a child develops nutritional marasmus, kwashiorkor or the intermediate form known as marasmic kwashiorkor. In a child who consumes much less food than required for his or her energy needs, energy is mobilized from both body fat and muscle. Gluconeogenesis in the liver is enhanced, and there is loss of subcutaneous fat and wasting of muscles. It has been suggested that under these circumstances, especially when protein intake is very low relative to carbohydrate intake (with the situation perhaps aggravated by nitrogen losses from infections), various metabolic changes take place which contribute to the development of oedema. More sodium and more water are retained, and much of the water collects outside the cardiovascular system in the tissues, which results in pitting oedema. The actual role of infection has not been adequately explained, but certain infections cause major increases in urinary nitrogen, which derives from amino acids in muscle tissue. There is not yet broad agreement on the actual cause of the oedema that is the hallmark of kwashiorkor. Most researchers agree that potassium deficiency and sodium retention are important in the pathogenesis of oedema. Some evidence supports the classical argument that oedematous malnutrition is a sign of inadequate protein intake. For example, oedema, fatty liver and a kwashiorkor- like condition can be induced in pigs and baboons on a protein- deficient diet. Kotaku. Luke Plunkett is a Contributing Editor based in Canberra, Australia. He has written a book on cosplay, designed a game about airplanes, and also runs cosplay.
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