Anemia Health Article

Other Causes

The two other primary causes of nutritional anemia are deficiencies in vitamin B₁₂ and folic acid, both of which are necessary for the production of DNA, RNA, and protein. Without these necessary factors, red blood cells can develop abnormally, or even die prematurely in the bone marrow where they are made. This leads to what is known as megaloblastic anemia.

Folate deficiency is most often caused by poor intestinal absorption or low intake of folate-rich foods, such as human milk, cow's milk, fruits, green vegetables, and certain meats. It is also caused by congenital defects in intestinal absorption. Just as with iron, folic acid requirements are highest during periods of rapid growth, particularly infancy and pregnancy. Folate-deficient children present with common symptoms of anemia, as well as chronic diarrhea. Folate deficiency can also occur with kwashiorkor or marasmus. If it occurs during pregnancy, folate deficiency can lead to neural tube defects, spontaneous abortions, and prematurity.

Vitamin B₁₂, derived from a substance called cobalamin, is mainly found in meats and other animal products—humans cannot synthesize this vitamin on their own. A good amount of its absorption depends on the presence of a substance called intrinsic factor (see sidebar). It does not normally occur with kwashiorkor or marasmus. Both folate and vitamin B₁₂ deficiencies have also been linked to cardiovascular disease, mood disorders, and increased frequency of chromosomal breaks (which may contribute to the development of cancer).

Treatment

Each of the important causes of nutritional anemia can be eradicated through prevention and treatment. Many countries have begun this process by instituting food supplementation programs in which grains and cereals are fortified with iron, folate, or vitamin B₁₂. Given adequate resources, these deficiencies can also be ameliorated with direct oral supplements of absorbable iron, vitamin B₁₂, and folic acid. Injectable forms of iron are also available. It has been found that the supplementation of vitamin A to at-risk populations improves anemia more efficiently than iron supplementation alone.

Treatment plans must also focus on the causes of anemia and therefore must include sanitation, treatment of infections such as malaria and HIV, and, most important, treatment of intestinal parasites. Much work is needed to address general malnutrition—not only concerning these deficiencies, but also other commonly occurring ones (e.g., vitamin A, zinc, copper, calcium). Programs dedicated to decreasing the rates of infection and illness in developing countries—through health education, immunization, sanitation, and appropriate treatment—will also contribute to a lower incidence and prevalence of worldwide anemia.

SEE ALSO KWASHIORKOR; MALNUTRITION; MARASMUS; NUTRITIONAL DEFICIENCY; VITAMINS, WATER SOLUBLE.

Seema P. Kumar

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