Anemia Health Article

Anemia

Anemia affects more than 30 percent of the world's population, and it is one of the most important worldwide health problems. It has a significant prevalence in both developing and industrialized nations. Causes of anemia include nutritional deficiencies, particularly of iron, vitamin B₁₂, and folate (folic acid); excess blood loss from menstruation or chronic illness and infection; ingestion of toxic substances, such as lead, ethanol, and other compounds; and genetic abnormalities such as thalassemia and sideroblastosis.

Anemia is caused by a deficiency in the intake and absorption elements required to make red blood cells. The condition is defined as one in which the blood is deficient in red blood cells, in hemoglobin, or in total volume. This results in blood that is incapable of meeting the oxygen needs of the body's tissues. Anemia is characterized by changes in the size and color of red blood cells. Red blood cells, or erythrocytes, are primarily responsible for oxygen transport from the lungs to the body's many cells. Hemoglobin is an oxygen-carrying protein in the red blood cell that incorporates iron into its structure. Therefore, iron is an essential building block of blood erythrocytes. When red blood cells are larger than normal, the anemia is termed macrocytic, and when they are smaller than normal, it is called microcytic. Normal red cell color is termed normochromic, and if the red cells appear pale, the anemia is called hypochromic. When extensive lab testing is not available for diagnosis, the use of a portable colorimeter can be used to detect anemia.

Iron-Deficiency Anemia

Anemia in the developing world is most commonly caused by an iron deficiency, which affects up to 50 percent of the population in some countries. Iron deficiency not only impairs the production of red cells in the blood, but also affects general cell growth and proliferation in tissues like the nervous system and the gastrointestinal tract. Red cells in a patient with iron-deficiency anemia are both microcytic and hypochromic.

Iron deficiency affects young children, adolescents, and women of reproductive age—three periods of rapid growth during which the body's iron needs are higher than normal. In children, iron requirements are highest between the ages of six and eighteen months, and can be ten times the requirement of a normal adult. Iron is commonly absorbed from both human milk and cow's milk, and, if consumed in good quantities, these sources can meet the body's iron needs. A deficiency can result from inadequate intake, or it can occur if milk remains the sole source of a child's nutrition after the age of four months, when iron needs exceed that provided by milk alone. Research in Chile has shown that 40 percent of children whose main source of nutrition was breast milk developed iron-deficiency anemia. Such children can appear tired and inattentive, and they can suffer from delayed motor development. Some children can even develop mild to moderate mental retardation as a result of iron-deficiency anemia. Recent research has shown that iron-deficiency anemia can also contribute to emotional development problems, with malnourished children acting more irritable and fussy.

Pregnant women can have up to double the requirement of iron for a normal adult, with the majority of the mother's iron being transferred to her growing fetus. Adult diets in most of the developing world tend to be iron-poor, and a low dietary intake can result in iron deficiency. Deficiency can also occur as a result of poor iron absorption due to gastrointestinal pathology, blood loss due to normal menstruation, blood loss from parasitic infections such as hookworm and malaria, and blood loss from chronic diarrhea—all of which are common in developing countries.