Anemias due to essential nutrient deficiencies.

Abstract

• Iron deficiency results from decreased intake in the setting of increased loss due to menstruation, childbirth or gastrointestinal bleeding. • Diets low in animal source foods are deficient in both iron and vitamin B 12 . • Atrophic gastritis (pernicious anemia) and other malabsorption syndromes are the major cause of vitamin B 12 deficiency megaloblastic anemia. • Folate deficiency megaloblastic anemia is often the result of alcoholism, drug therapy or malabsorption syndromes. • Vitamin B 12 deficiency causes elevated methylmalonic acid levels, and both B 12 deficiency and folate deficiency cause elevated homocysteine levels.