Dietary supplementation with conjugated linoleic acid induces anemia with combined features of megaloblastic and hemolytic anemia.

This study investigates whether dietary supplementation with conjugated linoleic acids (CLA) induces anemia in mice. Male Kunming White mice were randomly assigned to two groups: one fed a CLA-supplemented diet and the other a linoleic acid (LA)-supplemented diet as control. Compared with those in LA group, periodic manual erythrocyte counts revealed red blood cells (RBCs) in CLA group significantly reduced on days 47 (p < 0.05), 61 (p < 0.01), and 86 (p < 0.001). Complete blood count (CBC) analysis demonstrated that CLA group exhibited 48.96 % lower RBCs (p < 0.01) and 46.49 % reduced hematocrit (HCT, p < 0.01), but displayed 7.82 % higher mean corpuscular volume (MCV, p < 0.01) and a 41.77-fold increase in monocyte proportion (MONO %, p < 0.001). Brilliant cresyl blue (BCB)-stained blood smears showed reticulocyte counts in CLA group exceeding twice those of controls (p < 0.01). The levels of plasma vitamin B12 and folate in CLA-fed mice decreased by 24.72 % (p < 0.05) and 23.15 % (p < 0.01), respectively, while direct bilirubin levels increased significantly (p < 0.05). Electron microscopic images of the liver showed an enhanced phagocytic effect of Kupffer cells on RBCs. No intergroup differences were observed in RBC osmotic fragility, plasma iron levels, or renal erythropoietin (EPO) mRNA expression. These findings suggest CLA-induced anemia may result from nutritional deficiencies and/or enhanced phagocytic activity of the monocyte-macrophage system. We conclude that dietary CLA supplementation triggers anemia with mixed characteristics of both megaloblastic and hemolytic anemia.