Hypochromic anemia
（重定向自Greensickness）
Hypochromic anemia is a generic term for any type of anemia in which the red blood cells (erythrocytes) are paler than normal. (Hypo- refers to less, and chromic means color.) A normal red blood cell will have an area of pallor in the center of it; it is biconcave disk shaped. In hypochromic cells, this area of central pallor is increased. This decrease in redness is due to a disproportionate reduction of red cell hemoglobin (the pigment that imparts the red color) in proportion to the volume of the cell. Red blood cells will also be small (microcytic), leading to substantial overlap with the category of microcytic anemia. The most common causes of this kind of anemia are iron deficiency and thalassemia.