Effects of Several Low Protein Diets on the Serum Iron, Total Iron-binding Capacity, and Serum Cholesterol of Rats

Hemoglobin formation and the iron transport system as affected by feeding diets low in protein were investigated. Male rats, 8 weeks of age, were fed for 6 weeks at an elevation of 1.46 km (4800 feet), diets containing 3.5% protein from either 1) beef, 2) ground whole wheat or 3) ground whole wheat with added lysine. Other rats were fed a chow diet. Adequacy of these diets was measured at the end of the feeding period by the following determinations: hematocrit, hemoglobin, serum iron, total iron-binding capacity of the serum, and serum total cholesterol. An impairment in the iron-transport system and hemopoietic processes was indicated when rats were fed the diets with 3.5% protein from whole ground wheat, with or without added lysine, but not when they were fed a similar diet with 3.5% protein from beef. Rats fed the 3.5% beef- or wheat-protein diets had similar serum cholesterol values. Hematocrit and hemoglobin values and total iron-binding capacity of the serum of the chow-fed rats were somewhat higher than those reported in the literature as standard values for rats, suggesting an increase due to altitude.